Thanks guys! Dose, I think you'll find JimmyM to be a great resource. He posts a lot and I have learned a lot from reading what he has to say!
Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
SVT 3 Pro settings tutorial thread - please contribute your knowledge!
- Thread starter bassman_al
- Start date
I just parrot what the experts say
But thanks Al...I learn a lot from everyone on here, so it's a mutual thing.
Not to hi-jack my own thread, but thanks to the guys on TB, I finally got the courage up to try a set-up. It went very well and I saved myself a lot of money, even though it involved some trial and error, which on my basses means taking the neck on and off several times as I adjusted the truss rod. Empowerment!!!
I believe the hard-n-fast rule is; If it's a pedal, it goes in-line with the instrument. If it's a rack-mount device, it goes in the effects loop.
Hi all,
I had been having a problem with input level. When hitting the E string, most any note, with my thumb, I was getting a "thack" sound, with the LED light coming on each time. I suspected the input level was too hot, but I had been turning my Gain level down to almost nothing. Still the same sound, just at lower volume. I took a look at my BDDI settings and noted that all were set pretty low. Then I took a look at the "1/4" output" button and read the manual again. This button, IMO, is poorly worded on the unit. It would be more clear if it were marked as a pad switch, "-10dB," because that is what it is. I had it in the higher output setting, so I switched it to the lower setting for lower output level and that seems to have helped the "thack" problem.
Any thoughts out there on this problem? I noticed it particularly when using the P-bass I have with Dimarzio, which are very gainy high output pups.
I had been having a problem with input level. When hitting the E string, most any note, with my thumb, I was getting a "thack" sound, with the LED light coming on each time. I suspected the input level was too hot, but I had been turning my Gain level down to almost nothing. Still the same sound, just at lower volume. I took a look at my BDDI settings and noted that all were set pretty low. Then I took a look at the "1/4" output" button and read the manual again. This button, IMO, is poorly worded on the unit. It would be more clear if it were marked as a pad switch, "-10dB," because that is what it is. I had it in the higher output setting, so I switched it to the lower setting for lower output level and that seems to have helped the "thack" problem.
Any thoughts out there on this problem? I noticed it particularly when using the P-bass I have with Dimarzio, which are very gainy high output pups.
I had a 3Pro amp for awhile, and still use the SVP-Pro preamp which is similar. I think your initial post was a good explanation of how it works. Here are my thoughts:
First, I don't use the graphic at all. It's all solid state, so it sounds terrible when clipped. Besides, the rotary EQ is plenty for me.
As you said, the clip light is not a warning light. Except if it doesn't flash at all... that would be your warning that you need to turn it up.
The UltraHi switch is for bright tweetery highs (around 5khz), whereas the Bright switch is for more grindy high end (around 3kHz)
I agree that UltraLo should be used with caution (it's a classic mid scoop), but you can "voice" your bass by engaging UltraLo and then boosting mids using the variable midrange. I prefer the lower mid settings (1 and 2), but if you want a more modern tone you can try positions 3 and 4. The farthest right position (5) on the vari-mid is essentially low treble rather than high mid... you probably don't want to use that in conjunction with UltraLo.
Hope that helps a little... have fun with the amp!
First, I don't use the graphic at all. It's all solid state, so it sounds terrible when clipped. Besides, the rotary EQ is plenty for me.
As you said, the clip light is not a warning light. Except if it doesn't flash at all... that would be your warning that you need to turn it up.
The UltraHi switch is for bright tweetery highs (around 5khz), whereas the Bright switch is for more grindy high end (around 3kHz)
I agree that UltraLo should be used with caution (it's a classic mid scoop), but you can "voice" your bass by engaging UltraLo and then boosting mids using the variable midrange. I prefer the lower mid settings (1 and 2), but if you want a more modern tone you can try positions 3 and 4. The farthest right position (5) on the vari-mid is essentially low treble rather than high mid... you probably don't want to use that in conjunction with UltraLo.
Hope that helps a little... have fun with the amp!
put a square of gaffer tape over the peak light, disengage all the blender buttons, and tweak to taste
IMO the best thing you can do for a 3 pro is make sure the bias is set correctly - mosfets do need biasing. Read this. If you set the amp for a clean sound and it still sounds kinda dirty, particularly up around the 12th fret, there's a good chance the bias is off. I had trouble getting mine sorted so I went into a dealer to try a new one for a reality check. Every one in the shop was worse than mine! Makes quite a difference when it's right.
Great thread! One thing I've concluded is that there are about as many different ways of making use of this great amp as there are combinations of knob and switch settings!
A few miscellaneous observations, based on use of my 3PRO, as well as reading the schematic...
The first tube gain stage is before the Gain knob. If you have a hot signal, you can overdrive this one even at the minimum setting of that knob. The -15 dB button is before this gain stage to suit things like active basses or effects units with hot outputs.
The Peak LED is driven by multiple level sensors all through the preamp. I'm just guessing, but I'll bet the sensors are calibrated to light it at a signal level that corresponds to about the same amount of distortion at each stage.
The Tube Gain (or Plate Voltage) knob controls the power supply voltage to the tubes that drive the MOSFET output. Turning this down allows this driver stage to saturate and distort more. The driver stage is actually part of the power amp (it's driven by the Power Amp In jack, if that's used). The driver uses the two 12AU7 sections in push-pull fashion, so it can both source and sink a lot of current! This is necessary to drive the input capacitance of the MOSFETs.
The MOSFET output stage provides no voltage gain; it follows the voltage out of the driver stage, but supplies huge gobs of current. This means that unless you crank everything up and really saturate the MOSFETs (which I bet sounds ugly), the distortion characteristics are 100% tube.
With the Gain control up enough to flash the Peak LED with every note, I get a really nice retro tube distortion through the preamp, and can use the Master volume to get that cranked out tone at any volume level, or straight out the back to a mixer. Note that (unlike tube amps) it's fine to run this amp with no speaker connected, so bring just the head to the studio!
With the midrange frequency on setting "1" (around 200 Hz, I think), midrange slightly boosted (maybe to the 2:00 position), and the Bright switch on, my Rickenbacker sounds the best it ever has!
A few miscellaneous observations, based on use of my 3PRO, as well as reading the schematic...
The first tube gain stage is before the Gain knob. If you have a hot signal, you can overdrive this one even at the minimum setting of that knob. The -15 dB button is before this gain stage to suit things like active basses or effects units with hot outputs.
The Peak LED is driven by multiple level sensors all through the preamp. I'm just guessing, but I'll bet the sensors are calibrated to light it at a signal level that corresponds to about the same amount of distortion at each stage.
The Tube Gain (or Plate Voltage) knob controls the power supply voltage to the tubes that drive the MOSFET output. Turning this down allows this driver stage to saturate and distort more. The driver stage is actually part of the power amp (it's driven by the Power Amp In jack, if that's used). The driver uses the two 12AU7 sections in push-pull fashion, so it can both source and sink a lot of current! This is necessary to drive the input capacitance of the MOSFETs.
The MOSFET output stage provides no voltage gain; it follows the voltage out of the driver stage, but supplies huge gobs of current. This means that unless you crank everything up and really saturate the MOSFETs (which I bet sounds ugly), the distortion characteristics are 100% tube.
With the Gain control up enough to flash the Peak LED with every note, I get a really nice retro tube distortion through the preamp, and can use the Master volume to get that cranked out tone at any volume level, or straight out the back to a mixer. Note that (unlike tube amps) it's fine to run this amp with no speaker connected, so bring just the head to the studio!
With the midrange frequency on setting "1" (around 200 Hz, I think), midrange slightly boosted (maybe to the 2:00 position), and the Bright switch on, my Rickenbacker sounds the best it ever has!
I feel really stupid now....this was so far over my head. Are you saying to get tube like distortion turn the tube gain all the way down?
Yeah the TUBE GAIN knob is the plate voltage control to the preamp output, or amplifier driver as RD mentioned. When you turn the plate voltage down, the tube runs out of headroom. Tubes are voltage devices. No headroom and you start clipping. Clipping in a nice toobie goodness form...
Like the RED LED that is more of a signal indicator, the Tube Gain knob really works backwards compared to what you think it should, in this case by lowering the voltage they actually lower the stage gain. Tube Voltage is a more acurate description. This isn't that tough, read the manual it's available at www.AMPEG.com. You know, the manufacturer's website.
BOB
Like the RED LED that is more of a signal indicator, the Tube Gain knob really works backwards compared to what you think it should, in this case by lowering the voltage they actually lower the stage gain. Tube Voltage is a more acurate description. This isn't that tough, read the manual it's available at www.AMPEG.com. You know, the manufacturer's website.
BOB
I am so glad I was put onto this thread. I've had my SVT3 pro for about 4 years playing in a loud punk band and I have finally got the best out of the amp with a great sound. I use a Fender P and Rickenbacker which both sound awesome. I've been given some really helpful advice on this amp the best of which was the job of the gain LED!! So here's my settings;
Gain - 2. O'clock
Hi / Lo - OUT
Bass - 3. O'clock
Mid - 4. O'clock
Freq - 4
Treble - 2. O'Clock
Master 3. OClock
Tube gain - 2. O'clock
Now really happy with the amp.Thanks Guys agreat thread.
Mike
Gain - 2. O'clock
Hi / Lo - OUT
Bass - 3. O'clock
Mid - 4. O'clock
Freq - 4
Treble - 2. O'Clock
Master 3. OClock
Tube gain - 2. O'clock
Now really happy with the amp.Thanks Guys agreat thread.
Mike
Just picked this amp up yesterday....to me (fairly noob, TB educated)the Ampeg writeups werent that helpful. Your explanation nailed it, thanks dude.
Glad the thread is helping! Enjoy that amp.
Also, I discovered that my "thack" problem (mentioned earlier in the thread) when using my thumb to slap the E string was actually a technique problem. I noticed that my thumb was over the pickup, not close to the lower end of the neck by the last fret where it should have been all along. Once I noticed this, I moved my thumb and now the "thack" is gone. The "thack" was from the string actually hitting the pickup. Duh. I felt stupid once I figured that out, and feel more stupid writing this, but thought I should follow up since it might help clarify that my problem was not related to the amp or to the bass.
Carry on.
Also, I discovered that my "thack" problem (mentioned earlier in the thread) when using my thumb to slap the E string was actually a technique problem. I noticed that my thumb was over the pickup, not close to the lower end of the neck by the last fret where it should have been all along. Once I noticed this, I moved my thumb and now the "thack" is gone. The "thack" was from the string actually hitting the pickup. Duh. I felt stupid once I figured that out, and feel more stupid writing this, but thought I should follow up since it might help clarify that my problem was not related to the amp or to the bass.
Carry on.
I bought this amp yesterday and took it straight to a gig...so the 30 minutes or so I had with it in GC was the only setup/trial period before live use. Coupled it with an Acoustic 4x10, some minor levels tweeking and it was great on stage.
My next step (after all the roommates in the house wake up..I'm too nice) is to plug my pedalboard into it and see whats up there. Any advice from the scholars on optimization with dirt pedals and wah/filters? I'm gonna play all day on the knobs n see what I come up with, it;d be cool to see some feedback from others too.
My next step (after all the roommates in the house wake up..I'm too nice) is to plug my pedalboard into it and see whats up there. Any advice from the scholars on optimization with dirt pedals and wah/filters? I'm gonna play all day on the knobs n see what I come up with, it;d be cool to see some feedback from others too.
Anyone following this thread should also give this one a read, lots of info about replacing the tubes and maintenance with the fan/MOSFET bias.
http://www.talkbass.com/forum/showthread.php?t=425889
http://www.talkbass.com/forum/showthread.php?t=425889
So I am finally done futzing with my SVT-3 Pro...
I have to say, NOW I am impressed and very happy!
I did 3 things:
1) Complete retube. I went with eurotubes.com and ordered 4 standard JJ ECC83S tubes to replace the 12AX7's, and 1 JJ ECC82 for the 12AU7. There are options within these choices, but I went with the "standard" tubes. I dealt with Jay who was very helpful and thorough with explaining all the options. The improvement is nothing short of AMAZING!The amp literally came to life. I have more gain, but I didn't lose ability to get a nice clean tone (which was a concern). I also have much more overall volume (which I believe is due to the ECC82?). I no longer need to engage the EQ and bump the EQ level slider to get more volume. The tone is rich, warm, fat and punchy. If I want growl, I can get growl (although at the moment I still like my SansAmp Programmable Bass DI for the dirtier tones). The fan seemed to run a bit slower after the retube (albeit still noisy). It still ramped all the way up when the amp was first turned on, but it gradually slowed down to the point where I didn't hear the motor anymore, just the grinding sound I described before.
2) Replaced the fan. There was definitely something wrong with the original one. The (exact) replacement is by no means quiet, but it is a significant improvement to the degree where I'm no longer distracted by it when playing at low volume (the grinding noise is gone).
3) MOSFET bias. I read here in the forums that the 12AU7 is what feeds the MOSFETS, so I assume that replacing the 12AU7 (if not all of the tubes) had an effect on the amount of signal feeding the power amp section. I did notice some very low "solid state" sounding distortion/fuzz after the retube, which sounded exactly like what others have described on the forums. I carefully used a plastic potentiometer adjustment tool and nudged the MOSFET bias pot ever so slightly clockwise until the fuzz was gone. It literally took a hair's thickness of a turn. Since I did it by ear, I would like to try and find out the procedure for doing this with a meter (i.e., the right way) so I know it's correct for my new setup. Can anyone help in that regard?
So there you have it. Thanks to all the people here on TalkBass for your replies and helpful suggestions!
Just to add a few comments, I have a 2003 model and a 410HLF. I have had a lot of different heads including a mesa boogie, GK, Fender/sun, etc and this is by far my favorite one.
Before I list my settings, I just want to point out again that this amp is not over rated, but the preamp puts out a low signal. If you plug in another preamp into the effects return like a tech21 you will be blown away by the power amp. The master slider on the EQ is great for adding headroom for non-active basses.
With that said here is how I run my head, 5 piece 90's alt rock band.
Brite IN
Ultra High IN
Ultra Low IN
Gain 3 o'clock
Bass 2 o'clock
Mid 2 o'clock
mid feq 4
treble 1 o,clock
Tube Gain WFO
Mater to stage volume, usually 10-11 o'clock
One note, with my 2010 jazz deluxe, I use the bridge pickup, bump up the mids and lows on the bass.
With my Geddy Lee, I also run the bridge, but I switch on the eq and turn up the master slider in the right to match the volume on my deluxe, usually all the way up.
Before I list my settings, I just want to point out again that this amp is not over rated, but the preamp puts out a low signal. If you plug in another preamp into the effects return like a tech21 you will be blown away by the power amp. The master slider on the EQ is great for adding headroom for non-active basses.
With that said here is how I run my head, 5 piece 90's alt rock band.
Brite IN
Ultra High IN
Ultra Low IN
Gain 3 o'clock
Bass 2 o'clock
Mid 2 o'clock
mid feq 4
treble 1 o,clock
Tube Gain WFO
Mater to stage volume, usually 10-11 o'clock
One note, with my 2010 jazz deluxe, I use the bridge pickup, bump up the mids and lows on the bass.
With my Geddy Lee, I also run the bridge, but I switch on the eq and turn up the master slider in the right to match the volume on my deluxe, usually all the way up.
