Confusing distortion out of Eden WT800

bassicmelodies · #1 10-26-2010, 01:05 AM

Alright, so here's my deal. I've got the amp, and I'm noticing funny sounds. Sounds like my moog, but I'm playing my bass. The eden has two channels, one to bypass the built in compressor and the other to use it. They have a light on the amp saying that the compressor is active when you push it to that limit. So I'm getting the funny sound whenever the compressor light comes on and I'm in the lower register. Anything below middle C tends to agitate it. It's kinda neat sounding, but I'm concerned. In the meantime I can use the other channel without any sound issues.

Any clues?

Thanks so much.

Christopher

PS

I just emailed Eden, although last time I tried to get in touch with them it took weeks...

Son of Bovril · #2 10-26-2010, 01:32 AM

try the eden forum, you may find more help there. I can only speculate but maybe ther compressor isn't working properly...

bassicmelodies · #3 10-26-2010, 01:46 AM

http://www.eden-electronics.com/foru...sor,distortion

So it sounds like when the compressor is engaged and the preamp is pushed it distorts, from the sounds of it, the amps are designed that way. Strange. I'll post again when Eden responds. Thanks for the response.

Bluesbob · #4 10-26-2010, 07:02 AM

Quote:

Originally Posted by bassicmelodies

The eden has two channels, one to bypass the built in compressor and the other to use it. Any clues?

I have no idea. My WT800B (from Aug '05) has only one channel, although it has two outputs. It has a simple on/off button to bypass the compressor (which I always do). Maybe your amp was modified?

JTE · #5 10-26-2010, 08:48 AM

The WT-800 does NOT have two input channels. First, go to the Eden site and read the owners' manual. Especially pay attention to the section on setting levels. You've got an input gain control, a compressor by-pass, and a signal indicator LED. When the compressor is engaged the LED flashes when the signal is at the compressor's threshold. If the compressor is bypassed, the LED shows clipping of the input signal.

Second, if it's sounding like a sawtooth clipping, like a Moog, I'd suspect the 12AX7 pre-amp tube.

John

esa372 · #6 10-26-2010, 08:53 AM

Quote:

Originally Posted by bassicmelodies

So it sounds like when the compressor is engaged and the preamp is pushed it distorts...

I've heard stories about the Eden compressors in the WT800 distorting. However, I've owned two WT800(A) heads - one purchased in 1995; one in 2000 - and have never had any problem with the compression circuit.

Perhaps it's only an issue with the later (B & C) models...?

Rick Auricchio · #7 10-26-2010, 10:12 AM

Try cleaning the FX send and return jacks. Just run a 1/4" plug in and out several times. If you have contact cleaner, spray the plug beforehand. Or just patch a guitar cord from send to return.

It could be that the distortion has nothing to do with the compressor at all...

esa372 · #8 10-26-2010, 11:40 AM

Quote:

Originally Posted by Rick Auricchio

Try cleaning the FX send and return jacks. Just run a 1/4" plug in and out several times. If you have contact cleaner, spray the plug beforehand. Or just patch a guitar cord from send to return.

It could be that the distortion has nothing to do with the compressor at all...

Very true!

bassicmelodies · #9 10-26-2010, 11:47 AM

You're right JTE, it doesn't have two channels, I worded that poorly.

Quote:

Originally Posted by JTE

Second, if it's sounding like a sawtooth clipping, like a Moog, I'd suspect the 12AX7 pre-amp tube.

John

But if the distortion is only coming from when I use the compressor and it sounds fine when I bypass it, what could that have to do with the tube?

Secondly, cleaning the fx loop jacks, I'll try it, but I'm confused as to why you're having me do it. If I'm not running anything into, why would it be responsible for the distorted tone? Thanks Rick.

Thanks so much for the input!
Chris

JTE · #10 10-26-2010, 06:14 PM

Quote:

Originally Posted by bassicmelodies

You're right JTE, it doesn't have two channels, I worded that poorly.

But if the distortion is only coming from when I use the compressor and it sounds fine when I bypass it, what could that have to do with the tube?

Secondly, cleaning the fx loop jacks, I'll try it, but I'm confused as to why you're having me do it. If I'm not running anything into, why would it be responsible for the distorted tone? Thanks Rick.

Thanks so much for the input!
Chris

The FX loop jacks are switching jacks. So, even though you're not using them, any dirt that gets into the contacts can cause problems that come out like that. About once a year I spray a bit of Caig's DeOxit into the FX jacks on my WT-400, and insert & remove a 1/4" plug a few times.

I didn't catch that you're having the problem only when the compressor is switched in. So, if you set the level so the compressor light briefly flashes at your hardest attack, then switch off the compressor it sounds fine, but without changing any gain levels, you turn the compressor back on it distorts?

John

IntrepidCellist · #11 10-26-2010, 06:20 PM

With my WT400 I get a farty distortion sound on low notes (E and below) when the compressor is engaged. I disengage the compressor and it sounds fine. Guys on the Eden forum say that's normal.

okcrum · #12 10-26-2010, 06:37 PM

Hmmm, there are two OUTPUT channels in the WT800 - that's how they do biamp/bridged. The preamp is mono, though the signal path from the post-eq effects return is stereo.

The compressor is either on or off. I have an 800A that doesn't sound terrible when the compressor operates. I should check and see if it was modified. If so, then there are some undocumented mods to these. However, there has been much complaint about the sound of the older Eden compressors.

EDIT: The only mod I can see on the compressor is changing R19 from 120 to 1k ohms. I think this is for A models only. B and C would probably already have this. Eden will give you the schematics, OP, and the preamp board has the part designations on it as well.