Eden Forum Disappears

[Rip Van Dan]

Interesting, my Metro is written in @ 960 watts on the back panel (i assume peak watts)...it is a later Minnesota amp..it had a major issue with the master volume that i resolved with Deoxit contact enhancer after trying D5...otherwise it has been reliable.

I dont hear a significant difference between the 2 channels set flat...both have the enhance and comp (which i dont use the comp) and i do not have the footswitch.

I dont run the amp hard enough to kick on the fan for the most part..... but it is powerful and warm with a remarkable EQ on channel 2, even with the preamp dimed (which i prefer) it is clean and clear and takes pedals well....no matter the cabinet setup, it delivers.

Its a big amp in footprint, i pulled the amp and made a wood cabinet...i regard it is a classic amp design diminished by the fact it was a 'heavy' 2x10 combo amp which by today's standards is not desirable....low and very heavy, the casters were broken and the fur covering out of date lol.....still an iconic amp in my estimation and one well suited for rehearsal and studio imo.

That 960-watts on the back should be the power required to run it, not the output power. The peak power on it would be double the rms watt rating. Yours is probably the one rated at 630-watts into 2Ω so peak power would be double that.

My first Eden amp was a 2008 Eden Nemesis RS400 that proclaimed its presence with big blue LED's spelling out "Nemesis". It has an all FET front end as all the Nemesis amps did. I was amazed at the clarity, body, and versatility of the sound. It replaced a GK Backline 250 amp that I always struggled to get any decent sound out of. Then in 2010 I bought my WT500/800 directly from David Nordschow (was amp he used to design Eden cabs) and was able to hear the difference between the very clear Nemesis FET front end and the warmer WT with the tube used in the impedance matching section to generate that warmth. It wasn't a huge difference but I could easily tell the difference and I much prefer the warmth in the sound.

I still hang onto that Nemesis RS400 as a back up and I did end up using it for gigs during the two months I had my WT in the shop after dropping it on concrete. The main problem was the toroidal transformer was loosened by the jolt and rotated enough to cause distortion. They realigned it, tightened it down, and went through the rest of the amp while they had it. Was a simple fix, but was a 2-month waiting queue. That RS400 worked flawlessly and I used it again in 2018 at a small brewpub to run an Eden EX-112 before I got a small class D Eden TN-226 amp for that purpose (4.7-lbs, vs 15-lbs).

That channel 2 is basically the same preamp that I have on my WT500/800. It is amazingly versatile with those three semi-parametric controls. About the only adjustment I make on that with my passive Jazz is to boost the low-mids at ~250Hz to 1:30. I run everything else flat with the Enhance off and the auto-compressor off.

You know Eden actually sold the head of that amp separately for a year back in 2004. Evidently it didn't have as much demand as they though it would because it was gone in 2005. Here's a picture of it from the 2004 catalog:

They put it in a rat-fur covered wooden rack. Weight of the combo is 78-lbs. but didn't see a listing for the weight of the head by itself. Distortion was rated at less than 0.06%.

 

[agedhorse]

Note that peak power is nothing more than a different mathematical way to describe the power of the same waveform. For example any amp that delivers 500 watts RMS will also be delivering 1000 watts peak.

 

[ChrisPbass]

From what little I know about Eden (I'm a late starter), I can imagine myself as being a fan and user.

Since they're no longer in business, I don't mess with them, though...

I do get tempted when I see that WT800 on GC's used site, but (at $700) I've resisted.

I have a 400 and a 550. Honestly, the 400 needs a repair but functions. I got the 550 because I saw it on Craigslist for !!!$$$$200$$$$!!!! and I just had to get it. If you like the sound you will love them...
They are not light amps, not very heavy either, so people are getting rid of them. I love their sound.

 

[DavidEdenAria]

That 960-watts on the back should be the power required to run it, not the output power. The peak power on it would be double the rms watt rating. Yours is probably the one rated at 630-watts into 2Ω so peak power would be double that.

My first Eden amp was a 2008 Eden Nemesis RS400 that proclaimed its presence with big blue LED's spelling out "Nemesis". It has an all FET front end as all the Nemesis amps did. I was amazed at the clarity, body, and versatility of the sound. It replaced a GK Backline 250 amp that I always struggled to get any decent sound out of. Then in 2010 I bought my WT500/800 directly from David Nordschow (was amp he used to design Eden cabs) and was able to hear the difference between the very clear Nemesis FET front end and the warmer WT with the tube used in the impedance matching section to generate that warmth. It wasn't a huge difference but I could easily tell the difference and I much prefer the warmth in the sound.

I still hang onto that Nemesis RS400 as a back up and I did end up using it for gigs during the two months I had my WT in the shop after dropping it on concrete. The main problem was the toroidal transformer was loosened by the jolt and rotated enough to cause distortion. They realigned it, tightened it down, and went through the rest of the amp while they had it. Was a simple fix, but was a 2-month waiting queue. That RS400 worked flawlessly and I used it again in 2018 at a small brewpub to run an Eden EX-112 before I got a small class D Eden TN-226 amp for that purpose (4.7-lbs, vs 15-lbs).

That channel 2 is basically the same preamp that I have on my WT500/800. It is amazingly versatile with those three semi-parametric controls. About the only adjustment I make on that with my passive Jazz is to boost the low-mids at ~250Hz to 1:30. I run everything else flat with the Enhance off and the auto-compressor off.

You know Eden actually sold the head of that amp separately for a year back in 2004. Evidently it didn't have as much demand as they though it would because it was gone in 2005. Here's a picture of it from the 2004 catalog:

View attachment 5311418

They put it in a rat-fur covered wooden rack. Weight of the combo is 78-lbs. but didn't see a listing for the weight of the head by itself. Distortion was rated at less than 0.06%.

Thanks for the info! I do run it flat mostly but occasionally move the enhance control up a bit.

For Gibson EB0 types i back the 150ish range off maybe to 10:30 to 11:00, sometimes boost 1.5 to 2k range a bit which drastically changes the sound to where you could not guess what bass it is...comp off as well but i do add a bit of offboard comp at times

Think i mentioned the preamp is usually dimed (or close)...for passive J bass pretty much flat EQ as you do....i do play around with the semi parametric and enhance especially at whisper volumes just for fun...its amazing sometimes how a slight EQ tweak can really bring out playing with a pick for example and will definitely reveal any mistakes or fret noise (which i really like)...i can imagine this amp working with oddball basses and im guessing it would record well.

 

[moon-bass]

hey @Rip Van Dan you've always been a big help and i appreciate all of your knowledge. I recently scored a Navigator 1000 (Powered Navigator, WTX-1000N). I didn't even know that this amp existed, I had been looking for a light weight replacement for my WT800 and this fit the bill.

I don't know much about the amp - do you have any insight that you can share? I couldn't find much on it online.

It needs a good cleaning (been meaning to get to it for awhile) and possibly a tube replacement. At first it was very noisy, a cursory cleaning fixed most of it, but it has a high end "hiss" that's pretty audible while not playing. Any thoughts?

Thanks in advance for your help!

 

[Rip Van Dan]

hey @Rip Van Dan you've always been a big help and i appreciate all of your knowledge. I recently scored a Navigator 1000 (Powered Navigator, WTX-1000N). I didn't even know that this amp existed, I had been looking for a light weight replacement for my WT800 and this fit the bill.

I don't know much about the amp - do you have any insight that you can share? I couldn't find much on it online.

It needs a good cleaning (been meaning to get to it for awhile) and possibly a tube replacement. At first it was very noisy, a cursory cleaning fixed most of it, but it has a high end "hiss" that's pretty audible while not playing. Any thoughts?

Thanks in advance for your help!

Hey "moon-bass" congrats on that score. The WTX1000N came out in 2010 and was included in the 2010/2011 catalog that came out near the end of 2010. It was only around for a couple of years and was not in the 2012 catalog.

The WTX1000N is a two channel class D power section attached to the Navigator preamp. You have a max of 1,000-watts rms available with 500-watts available in each channel. Weight is 11-pounds. By comparison the class A/B WT800C weighs in a 26-lbs. So it's a lightweight powerhouse amp. Each channel can put out 500-watts rms into 4Ω BUT it can't be bridged because it is a class D amp.

The cool thing about a 2-channel powerblock is that whatever you plug into one channel has no effect at all on what is plugged into the second channel. You could plug two 8Ω cabs into one side if you liked to make a 4Ω load, and a single 4Ω cab into thee other channel. Both channel's work just fine. You could plug in two 8Ω cabs to each side if you like and run all 4 cabs off that amp.

It also has a balance control like your WT800 does. That is handy if you have different size speakers on different channels. For instance perhpas a 410 in one channel and a 212 in thee other. If you want more of the 212 character in your soound you can just turn that balance control slowly towards the 212 side until you get the mix of sound you want.That is basically the same as your WT800 with the exception that there is no bridged mode with the WTX1000N.

It has all off the versatility and options of the WP-100 (Navigator preamp), but instead of being just a preamp, it has 1000-watts of output power hooked up to it. The other WT-series dual powerblock amps (WT500, WT600, & WT800) can all be bridged, combining the output of both power channels into on bridged output. That WTX1000N does not have and can not be operated in "bridged mode".

The bad news is that is one of the very few Eden manuals that I did not download from the old Orvis site before they were removed. I do however have a manual for the Navigator (WP-100) by itself, which will give you all of info on how to use the preamp section. I have attached that manual to this reply.

As far as a his goes, that could be a lot of things. Best thing to do is get some DeOxit 5 and some long handled Q-tips. Spray the Q-tip and then use it to clean the contacts of each 1/4" jack on the amp...there's a lot of them. The signal path goes through just about everything in the back and if one of the contacts gets corroded, you can get a his; an intermittent turn off and on; a sudden drop in volume; etc.

Very often a jack that you don't use is the one that gets corroded because a plug never rubs against the contacts to knock of any of the corrosion. Another thing you can do if you don't have any of those long-handled Q-tips handy is to take a 1/4" plug, spray some DeOxit5 on the barrel and tip and then move it in and out of each jack 10-times or so. If that doesn't clear it up, then it's tech time to find out what the problem really is.

 

[moon-bass]

Hey "moon-bass" congrats on that score. The WTX1000N came out in 2010 and was included in the 2010/2011 catalog that came out near the end of 2010. It was only around for a couple of years and was not in the 2012 catalog.

The WTX1000N is a two channel class D power section attached to the Navigator preamp. You have a max of 1,000-watts rms available with 500-watts available in each channel. Weight is 11-pounds. By comparison the class A/B WT800C weighs in a 26-lbs. So it's a lightweight powerhouse amp. Each channel can put out 500-watts rms into 4Ω BUT it can't be bridged because it is a class D amp.

The cool thing about a 2-channel powerblock is that whatever you plug into one channel has no effect at all on what is plugged into the second channel. You could plug two 8Ω cabs into one side if you liked to make a 4Ω load, and a single 4Ω cab into thee other channel. Both channel's work just fine. You could plug in two 8Ω cabs to each side if you like and run all 4 cabs off that amp.

It also has a balance control like your WT800 does. That is handy if you have different size speakers on different channels. For instance perhpas a 410 in one channel and a 212 in thee other. If you want more of the 212 character in your soound you can just turn that balance control slowly towards the 212 side until you get the mix of sound you want.That is basically the same as your WT800 with the exception that there is no bridged mode with the WTX1000N.

It has all off the versatility and options of the WP-100 (Navigator preamp), but instead of being just a preamp, it has 1000-watts of output power hooked up to it. The other WT-series dual powerblock amps (WT500, WT600, & WT800) can all be bridged, combining the output of both power channels into on bridged output. That WTX1000N does not have and can not be operated in "bridged mode".

The bad news is that is one of the very few Eden manuals that I did not download from the old Orvis site before they were removed. I do however have a manual for the Navigator (WP-100) by itself, which will give you all of info on how to use the preamp section. I have attached that manual to this reply.

As far as a his goes, that could be a lot of things. Best thing to do is get some DeOxit 5 and some long handled Q-tips. Spray the Q-tip and then use it to clean the contacts of each 1/4" jack on the amp...there's a lot of them. The signal path goes through just about everything in the back and if one of the contacts gets corroded, you can get a his; an intermittent turn off and on; a sudden drop in volume; etc.

Very often a jack that you don't use is the one that gets corroded because a plug never rubs against the contacts to knock of any of the corrosion. Another thing you can do if you don't have any of those long-handled Q-tips handy is to take a 1/4" plug, spray some DeOxit5 on the barrel and tip and then move it in and out of each jack 10-times or so. If that doesn't clear it up, then it's tech time to find out what the problem really is.

Thank you so much for your reply! You definitely went above and beyond like you always do You are definitely one of the good ones on TB.

And yeah, I know this needs a good cleaning - it looks like there is either coffee or pop spilled on the front.

Here's something that I have never seen before - when I plug a bass directly into the amp, I hear the hiss when I turn up the master volume past 5-6. When I plug one of my pedal boards in, the hiss is almost gone - it's only apparent when I crank the master volume to 9-10. I need to do more troubleshooting and cleaning, perhaps check the tube ... but thought that was weird. I live in a terrible, terrible place for interference so maybe the pedals are providing some sort of filter or buffer .. I dunno, but it give me hope!

Anyways thanks again! I am totally digging this amp!

 

[Rip Van Dan]

Thank you so much for your reply! You definitely went above and beyond like you always do You are definitely one of the good ones on TB.

And yeah, I know this needs a good cleaning - it looks like there is either coffee or pop spilled on the front.

Here's something that I have never seen before - when I plug a bass directly into the amp, I hear the hiss when I turn up the master volume past 5-6. When I plug one of my pedal boards in, the hiss is almost gone - it's only apparent when I crank the master volume to 9-10. I need to do more troubleshooting and cleaning, perhaps check the tube ... but thought that was weird. I live in a terrible, terrible place for interference so maybe the pedals are providing some sort of filter or buffer .. I dunno, but it give me hope!

Anyways thanks again! I am totally digging this amp!

If you are talking about running your master at 5 or 6 o'clock, that's pretty much wide open and would expect the amp to clip long before you get there. If you mean 12-noon to 1-o'clock, that's probably close the max the amp puts out before clipping.

I have never, ever, cranked my Eden amps up that high. With my DNS-410 cab, if I run my WT500/800 bridged at 800 watts into it, I can't run my master up to 10:30 at a wide open Music Festival I get told to turn down. Are you setting your gain to get the gain-set light to dance on your lowest and loudest notes? If not you will need to do that before you start cranking up the master.

Keep the master at 9 o'clock or lower while slowly turning up the gain until you get that light blinking (not staying off and not always lit, but blinking). That will give you the clearest, cleanest, lowest distortion signal for the power section to amplify. If you have your gain set too low, the result will be weak and noisy sound. If you run it too high, you'll get a lot of distortion, and NOT in a good way. With my passive Jazz, I typically have the gain set at about 2 o'clock.

I would suggest you adjust the gain first with just the bass plugged in. Do it with everything flat, the enhance turned off and the compressor off too. Once you get that light to flashing, you have a baseline to work from. Then go ahead and set up your EQ and Enhance and auto-compressor if you want or need to. After making those changes go back to the gain and adjust again to adjust the gain for changes you made. Once you have your EQ set, then finally plug in your board and engage any of the pedals that you constantly run. Once you're happy with that, check your gain-set light to see if it still flashes on your lowest, loudest notes. If it doesn't flash - increase the gain. If it doesn't ever go off - turn the gain down. Then note where your gain is. As long as you use the same bass and pedals, you should be good with just setting it there all the time.

When I used to manage record stores back in the mid and late 70's when vinyl was the primary medium, a 50:1 (50 to 1) signal to noise ratio was the defining measurement between being hi-fidelity and not being hi-fidelity. In other words the signal (music) needed to be 50db louder than the noise the record made spinning or the tape made moving across the heads.

Power sections do generate some noise themselves even if they are capable of producing a signal with a less than 0.1% THD rating (Total Harmonic Distortion) and like any source, you always want to keep a wide difference in the signal to noise ratio. If you send a weak signal to the power section and crank the power section way up basically using the gain as the volume control, you're going to get a weak and noisy (hissy) signal out of it. If, on the other hand, you set the gain appropriately, sending a strong, clean, clear, signal to the power section to amplify, you will get outstanding fidelity at all levels and that amp can certainly put out a lot of clean power.

That amp is not normally a hiss bomb. If it still hisses with the gain set as described above (much hotter than the master), I'd go ahead and spend 20-minutes to half an hour cleaning those jacks before trying to really diagnose anything. What you describe sounds to me like running the gain too low and sending the power section a weak signal to amplify.

Another thought, if you haven't exercised the pots on that amp (rotated them all the way to the left and right multiple times to help clear dirt from the contacts), a dirty pot can also cause that sound. If they are dirty, when you rotate the pots back and forth you'll typically hear a crackling sound. Rotating the pot multiple times fairly quickly will often clean them to the point they are usable again. Beware of spraying anything into the pots themselves. More often than not that will ruin the pot or gunk it up in a very short time to a point it is no longer usabel.

**Caveat** If you end up needing to replace the pots, hang onto the original knobs. The only place I know of now where you can get the replacement knobs for the Eden WT amps is Israel via E-bay, and they are about $17 each for the knob, pot not included.

These are just some things you can do without spending money that may do the trick for you, but will not fix an actual electronic fault. If none of these do the trick, then it really is tech time to track down the fault and fix it.

 

[moon-bass]

If you are talking about running your master at 5 or 6 o'clock, that's pretty much wide open and would expect the amp to clip long before you get there. If you mean 12-noon to 1-o'clock, that's probably close the max the amp puts out before clipping.

I have never, ever, cranked my Eden amps up that high. With my DNS-410 cab, if I run my WT500/800 bridged at 800 watts into it, I can't run my master up to 10:30 at a wide open Music Festival I get told to turn down. Are you setting your gain to get the gain-set light to dance on your lowest and loudest notes? If not you will need to do that before you start cranking up the master.

Keep the master at 9 o'clock or lower while slowly turning up the gain until you get that light blinking (not staying off and not always lit, but blinking). That will give you the clearest, cleanest, lowest distortion signal for the power section to amplify. If you have your gain set too low, the result will be weak and noisy sound. If you run it too high, you'll get a lot of distortion, and NOT in a good way. With my passive Jazz, I typically have the gain set at about 2 o'clock.

I would suggest you adjust the gain first with just the bass plugged in. Do it with everything flat, the enhance turned off and the compressor off too. Once you get that light to flashing, you have a baseline to work from. Then go ahead and set up your EQ and Enhance and auto-compressor if you want or need to. After making those changes go back to the gain and adjust again to adjust the gain for changes you made. Once you have your EQ set, then finally plug in your board and engage any of the pedals that you constantly run. Once you're happy with that, check your gain-set light to see if it still flashes on your lowest, loudest notes. If it doesn't flash - increase the gain. If it doesn't ever go off - turn the gain down. Then note where your gain is. As long as you use the same bass and pedals, you should be good with just setting it there all the time.

When I used to manage record stores back in the mid and late 70's when vinyl was the primary medium, a 50:1 (50 to 1) signal to noise ratio was the defining measurement between being hi-fidelity and not being hi-fidelity. In other words the signal (music) needed to be 50db louder than the noise the record made spinning or the tape made moving across the heads.

Power sections do generate some noise themselves even if they are capable of producing a signal with a less than 0.1% THD rating (Total Harmonic Distortion) and like any source, you always want to keep a wide difference in the signal to noise ratio. If you send a weak signal to the power section and crank the power section way up basically using the gain as the volume control, you're going to get a weak and noisy (hissy) signal out of it. If, on the other hand, you set the gain appropriately, sending a strong, clean, clear, signal to the power section to amplify, you will get outstanding fidelity at all levels and that amp can certainly put out a lot of clean power.

That amp is not normally a hiss bomb. If it still hisses with the gain set as described above (much hotter than the master), I'd go ahead and spend 20-minutes to half an hour cleaning those jacks before trying to really diagnose anything. What you describe sounds to me like running the gain too low and sending the power section a weak signal to amplify.

Another thought, if you haven't exercised the pots on that amp (rotated them all the way to the left and right multiple times to help clear dirt from the contacts), a dirty pot can also cause that sound. If they are dirty, when you rotate the pots back and forth you'll typically hear a crackling sound. Rotating the pot multiple times fairly quickly will often clean them to the point they are usable again. Beware of spraying anything into the pots themselves. More often than not that will ruin the pot or gunk it up in a very short time to a point it is no longer usabel.

**Caveat** If you end up needing to replace the pots, hang onto the original knobs. The only place I know of now where you can get the replacement knobs for the Eden WT amps is Israel via E-bay, and they are about $17 each for the knob, pot not included.

These are just some things you can do without spending money that may do the trick for you, but will not fix an actual electronic fault. If none of these do the trick, then it really is tech time to track down the fault and fix it.

Thank you again! I really appreciate your time and your knowledge!

 

[moon-bass]

If you are talking about running your master at 5 or 6 o'clock, that's pretty much wide open and would expect the amp to clip long before you get there. If you mean 12-noon to 1-o'clock, that's probably close the max the amp puts out before clipping.

I have never, ever, cranked my Eden amps up that high. With my DNS-410 cab, if I run my WT500/800 bridged at 800 watts into it, I can't run my master up to 10:30 at a wide open Music Festival I get told to turn down. Are you setting your gain to get the gain-set light to dance on your lowest and loudest notes? If not you will need to do that before you start cranking up the master.

Keep the master at 9 o'clock or lower while slowly turning up the gain until you get that light blinking (not staying off and not always lit, but blinking). That will give you the clearest, cleanest, lowest distortion signal for the power section to amplify. If you have your gain set too low, the result will be weak and noisy sound. If you run it too high, you'll get a lot of distortion, and NOT in a good way. With my passive Jazz, I typically have the gain set at about 2 o'clock.

I would suggest you adjust the gain first with just the bass plugged in. Do it with everything flat, the enhance turned off and the compressor off too. Once you get that light to flashing, you have a baseline to work from. Then go ahead and set up your EQ and Enhance and auto-compressor if you want or need to. After making those changes go back to the gain and adjust again to adjust the gain for changes you made. Once you have your EQ set, then finally plug in your board and engage any of the pedals that you constantly run. Once you're happy with that, check your gain-set light to see if it still flashes on your lowest, loudest notes. If it doesn't flash - increase the gain. If it doesn't ever go off - turn the gain down. Then note where your gain is. As long as you use the same bass and pedals, you should be good with just setting it there all the time.

When I used to manage record stores back in the mid and late 70's when vinyl was the primary medium, a 50:1 (50 to 1) signal to noise ratio was the defining measurement between being hi-fidelity and not being hi-fidelity. In other words the signal (music) needed to be 50db louder than the noise the record made spinning or the tape made moving across the heads.

Power sections do generate some noise themselves even if they are capable of producing a signal with a less than 0.1% THD rating (Total Harmonic Distortion) and like any source, you always want to keep a wide difference in the signal to noise ratio. If you send a weak signal to the power section and crank the power section way up basically using the gain as the volume control, you're going to get a weak and noisy (hissy) signal out of it. If, on the other hand, you set the gain appropriately, sending a strong, clean, clear, signal to the power section to amplify, you will get outstanding fidelity at all levels and that amp can certainly put out a lot of clean power.

That amp is not normally a hiss bomb. If it still hisses with the gain set as described above (much hotter than the master), I'd go ahead and spend 20-minutes to half an hour cleaning those jacks before trying to really diagnose anything. What you describe sounds to me like running the gain too low and sending the power section a weak signal to amplify.

Another thought, if you haven't exercised the pots on that amp (rotated them all the way to the left and right multiple times to help clear dirt from the contacts), a dirty pot can also cause that sound. If they are dirty, when you rotate the pots back and forth you'll typically hear a crackling sound. Rotating the pot multiple times fairly quickly will often clean them to the point they are usable again. Beware of spraying anything into the pots themselves. More often than not that will ruin the pot or gunk it up in a very short time to a point it is no longer usabel.

**Caveat** If you end up needing to replace the pots, hang onto the original knobs. The only place I know of now where you can get the replacement knobs for the Eden WT amps is Israel via E-bay, and they are about $17 each for the knob, pot not included.

These are just some things you can do without spending money that may do the trick for you, but will not fix an actual electronic fault. If none of these do the trick, then it really is tech time to track down the fault and fix it.

Hey man, I just want to say thanks again for your help! As it turns out it was operator error, and it needed a little cleaning. Amp is in top-top shape now, and it sounds killer!

 

[Rip Van Dan]

Hey man, I just want to say thanks again for your help! As it turns out it was operator error, and it needed a little cleaning. Amp is in top-top shape now, and it sounds killer!

Happy to hear it! Rock On!!

 

[gerryjazzman]

Glad this rolling post on Eden gear exists!

Just picked up a used WT300. It's my first real bass amp, and I'm really enjoying the sound and sensitivity of the controls. There are a couple things in the thread that have been briefly touched on, but I'm still curious about.

I'm not studied on electronics. Know my way around a soldering iron, but that's about it. I've seen it mentioned in this thread that the preamp tube in the WT series amps is in the impedance matching section. In theory and practice, what is the benefit of having it there, and what is it 'doing'? I'm an idiot, so an ELI5 would be helpful, ha.

@gerryjazzman mentioned earlier in the thread about owning a WT300, and doing a DIY mod to add compressor defeat with a push/pull pot. Does anyone know if this is a mod for the WT300 that is documented in any way? I'd love to try it if it's straightforward / doesn't require a 400 series board, etc. If it's not documented, but someone here has some pointers, I'd be happy to be a guinea pig, and document it for posterity.

You rang? Wow, I totally forgot that I posted that here. That was back in the day when you could get replacement parts and schematics directly from Eden. I have the schematics for the WT300 and WT400 and was able to compare them to see how they implemented the compressor defeat. Fairly simple actually. It did require removing the old pot (PCB mount) from the board, replacing it with the new (from Eden at the time) push-pull enhance pot, and soldering a few wires from the new pot to the board. From what I recall the WT300 board was not designed for the push pull pot I had to solder a few wires from the pot to the board for the enhance control in addition to the two switch terminals for the compressor defeat. The only thing different is that the WT400 has a separate LED for the compression which the WT300 does not have. I can open her up and take a picture of the mod and post it here. I can also provide the schematics for the two amps to show where the mod goes. Give me a day or two and I can post that stuff.

On a side note, I wished that the power mod from 300 to 400 was documented as I was considering doing that as well but it's not really necessary now since I don't play out any more and don't need the extra power.

 

[Rip Van Dan]

Glad this rolling post on Eden gear exists!

Just picked up a used WT300. It's my first real bass amp, and I'm really enjoying the sound and sensitivity of the controls. There are a couple things in the thread that have been briefly touched on, but I'm still curious about.

I'm not studied on electronics. Know my way around a soldering iron, but that's about it. I've seen it mentioned in this thread that the preamp tube in the WT series amps is in the impedance matching section. In theory and practice, what is the benefit of having it there, and what is it 'doing'? I'm an idiot, so an ELI5 would be helpful, ha.

@gerryjazzman mentioned earlier in the thread about owning a WT300, and doing a DIY mod to add compressor defeat with a push/pull pot. Does anyone know if this is a mod for the WT300 that is documented in any way? I'd love to try it if it's straightforward / doesn't require a 400 series board, etc. If it's not documented, but someone here has some pointers, I'd be happy to be a guinea pig, and document it for posterity.

The reason that the 12ax7 tube is in the impedance matching section is that it runs there within some very specific parameters so it doesn't change with any gain adjustments. David Nordschow did it that way because he could get the warmth of sound he wanted without the distortion. All of his amps have very low Total Harmonic Distortion (THD) and he wanted to warm up the sound while still keeping it clear and clean.

I have both an Eden Nemesis RS400 (400-watts rms into 4Ω) and a WT500/800 that David actually used to design all the cabs from 1999 until he left Eden on 2009. The RS400 has an all solid-state FET preamp and the WT has the hybrid preamp with the tube in the impedance matching section. Both have great sound but the WT has a warmth to it that is missing from the RS400.

If that tube was put in the gain section, like many/most hybrid amps do, then as you raise the gain you start to get overdrive. Continue raising it for more and more overdrive and finally distortion. David did not want distortion he just wanted the "tube warmth" that tube preamps are well known for. By putting it in the impedance matching section he could assure that it would not generate overdrive or distortion.

Using a cathode follower, as @agedhorse explained, the voltage gain would always be less than one. That's also why rolling 12ax7 or 7025 tubes in the Eden WT amps makes virtually no difference in the sound. Whereas when a tube is used in the gain section for overdrive, you can get a lot of different sounds out of the different brands you try, as you increase the gain through them.

Regarding the compressor defeat switch, yes that was a mod Eden would do back in the Montrose days and perhaps the Mundelein days too. I believe that @Bassmann1968 (Armin) can give us more info on it. I'm not sure its a DIY thing that someone with neophyte electronics information should attempt. But Armin is definitely not a neophyte and he should be able to tell us all about it. Lord knows he owns a mountain (a pyramid anyhow) of Eden gear!

 

[frankie5string]

The reason that the 12ax7 tube is in the impedance matching section is that it runs there within some very specific parameters so it doesn't change with any gain adjustments. David Nordschow did it that way because he could get the warmth of sound he wanted without the distortion.

I hate to break it to you, but if the circuit is doing something to the input to make it sound warmer, it is indeed distorting the signal. It may not be an "overdrive" but it's distorting the "pure" (pure is such a bollocks term, anyway) signal to warm it up.

There is no magic to a 12AX7. It was designed to do a specific thing.

 

[DavidEdenAria]

The reason that the 12ax7 tube is in the impedance matching section is that it runs there within some very specific parameters so it doesn't change with any gain adjustments. David Nordschow did it that way because he could get the warmth of sound he wanted without the distortion. All of his amps have very low Total Harmonic Distortion and he wanted to warm up the sound while still keeping it clear and clean.

I have both an Eden Nemesis RS400 (400-watts rms into 4Ω) and a WT500/800 that David actually used to design all the cabs from 1999 until he left Eden on 2009. The RS400 has an all solid-state FET preamp and the WT has the hybrid preamp with the tube in the impedance matching section. Both have great sound but the WT has a warmth to it that is missing from the RS400.

If that tube was put in the gain section, like many/most hybrid amps do, then as you raise the gain you start to get overdrive. Continue raising it for more and more overdrive and finally distortion. David did not want distortion he just wanted the "tube warmth" that tube preamps are well known for. By putting it in the impedance matching section he could assure that it would not generate overdrive or distortion.

Using a cathode follower, as @agedhorse explained, the voltage gain would always be less than one. That's also why rolling 12ax7 or 7025 tubes in the Eden WT amps makes virtually no difference in the sound. Whereas when a tube is used in the gain section for overdrive, you can get a lot of different sounds out of the different brands you try, as you increase the gain through them.

Regarding the compressor defeat switch, yes that was a mod Eden would do back in the Montrose days and perhaps the Mundelein days too. I believe that @Bassmann1968 (Armin) can give us more info on it. I'm not sure its a DIY thing that someone with neophyte electronics information should attempt. But Armin is definitely not a neophyte and he should be able to tell us all about it. Lord knows he owns a mountain (a pyramid anyhow) of Eden gear!

The Metro has the comp defeat knob, one advantage to the Metro....i made a head box for my Metro...its been a stellar amp both channels are great and do sound different.

Which amps have the defeat comp knob?

 

[gerryjazzman]

So glad to catch you! Stars aligned!



That would be amazing. Based on your comment, it sounds like the mod isn't too scary. There is the question of getting the right pot though. I'll dig through some catalogs, see if I can find something available. I'll take some photos/video as I go along, & if I succeed, will post for any future owners who want to try out the mod. If I fail, I'll warn people, haha.

Compressor defeat would be a real improvement on the WT300. For my tastes, it's the only thing I feel is missing.

@Rip Van Dan - Thank you so much for the insight, that is a great explanation on what I was wondering re: the tube placement and role. Cheers.

One of the things I remembered after I took a look at it is to get the pot out and put the new one in is you have to take the preamp board out to get to the solder pads underneath which requires taking off all the knobs and removing all the pot nuts from the front panel. I also think I had to modify the new pot by flipping the switch so the terminals faced up, since the PCB does not have holes for the switch. Electrically the mod is simple, but mechanically it gets involved.

If, however you just want to permanently disable the compressor, it can be done by just installing a jumper wire on the top ot the board, no need to remove it. It would be reversible. It’ll be more clear when I post pics.

 

[Rip Van Dan]

The Metro has the comp defeat knob, one advantage to the Metro....i made a head box for my Metro...its been a stellar amp both channels are great and do sound different.

Which amps have the defeat comp knob?

From the WT400 on, virtually all the WT amps after that had the pull-to-defeat knob or in some cases a button to engage or disengage it. The Eden TN (Terra Nova) series have a button you need to depress to activate the auto-compressor.

 

[gerryjazzman]

As promised, here is the info for the WT300 Compressor Mod. The two attached PDF's are the original preamp schematics for the WT300 and WT400 I got from Eden. Not the best clarity but you can see what is going on. I captured the areas of interest on the schematics to zoom into the area where the compressor defeat is located. Here is the WT400:

Note that the defeat just grounds the junction of R23 (1K) and the emitter of Q6, while disconnecting the compressor LED (LED2). The WT300 does not have this LED since it just uses LED3 for both the level and compressor action.

Here is where you can add the switch to the WT300:

Note that the 1K resistor is now R19 in the WT300 and the transistor is now Q4, but essentially the same thing, grounding that junction to defeat the compressor. The compressor LED is not used so the switch is a simple SPST switch.

Here is how the mod looks in my amp:

The orange wire to the end of R19 and the green wire tied to the anode of LED1 which was just a convenient ground point. The 3 pot terminals went right into the original PCB holes, but it's now obvious that I was able to flip the switch upside down to have access to the switch terminals (don't ask, I don't remember how I did that , it's been too long).

Here is the overall view of the whole preamp board:

As I mentioned in my previous post, I had to remove the preamp board the swap out the enhance pot which was a bit of a chore. However, you could see if you are fine with just permanently disabling the compressor, you could just add a jumper from R19 and the LED1 anode without any other changes or removing the whole PCB. It's of course reversible by just removing the jumper.

Hope this all helps. Ask me any questions.

 

[Rip Van Dan]

As promised, here is the info for the WT300 Compressor Mod. The two attached PDF's are the original preamp schematics for the WT300 and WT400 I got from Eden. Not the best clarity but you can see what is going on. I captured the areas of interest on the schematics to zoom into the area where the compressor defeat is located. Here is the WT400:

View attachment 5340888

Note that the defeat just grounds the junction of R23 (1K) and the emitter of Q6, while disconnecting the compressor LED (LED2). The WT300 does not have this LED since it just uses LED3 for both the level and compressor action.

Here is where you can add the switch to the WT300:

View attachment 5340905

Note that the 1K resistor is now R19 in the WT300 and the transistor is now Q4, but essentially the same thing, grounding that junction to defeat the compressor. The compressor LED is not used so the switch is a simple SPST switch.

Here is how the mod looks in my amp:

View attachment 5340915


The orange wire to the end of R19 and the green wire tied to the anode of LED1 which was just a convenient ground point. The 3 pot terminals went right into the original PCB holes, but it's now obvious that I was able to flip the switch upside down to have access to the switch terminals (don't ask, I don't remember how I did that , it's been too long).

Here is the overall view of the whole preamp board:

View attachment 5340930

As I mentioned in my previous post, I had to remove the preamp board the swap out the enhance pot which was a bit of a chore. However, you could see if you are fine with just permanently disabling the compressor, you could just add a jumper from R19 and the LED1 anode without any other changes or removing the whole PCB. It's of course reversible by just removing the jumper.

Hope this all helps. Ask me any questions.

Just an FYI: At least since February 6, 2003 the WT400 already came with compressor bypass by pulling the enhance knob. You'll see that noted on page 3 of the WT-400 manual released on Feb. 2, 2003. It's under the heading Compressor Bypass. I presume your schematic is dated earlier than that.

That's a really simple way to defeat the auto-compressor on the WT-300 though and the pictures of the fix are great. I personally always bypass my compress on my WT500/800 because it sounds so harsh. However on my TN-226 class D amp (225-watts rms into 4Ω), the auto-compressor is much smoother and more musical. I solved a power clipping problem when our group got too loud in a small venue by engaging the auto compressor.

I engaged the compressor and turned the gain up a bit (gain control acts as threshold control when auto-compressor is engaged). It really didn't sound different and I still seemed to have all the dynamics I did before, but it stopped that power clipping light immediately. Granted all it needed to do was compress the peaks and it did that smoothly and easily but I was impressed it did that without any noticeable change in my sound. I was very pleased with it.

The auto-compressor on my WT500/800 though is much harsher and seems to have a much harder knee. I would use it for slap, but that's about it, so I always keep it bypassed on my big Eden amp.

 

[gerryjazzman]

You're right about the WT400 already having the compressor defeat. That's what I was comparing, the WT400 schematic which already incorporated the compressor defeat by pulling the enhance knob. I was using that as a reference to implement the defeat for the WT300 which doesn't have the defeat. I have the older schematics for the WT500/600/800 preamp as well which look the same as the WT300 with no defeat as well. Did they add the pull knob in the later versions? I have no experience with those.