Wanted: Opinion on using a tube preamp with a SS amp

[JimDep]

I'm wondering about the benefit of getting one of those tube pedal preamps to run in front of a solid state amp, such as a Marshall AVT 275, PV Bandit or a Stereo Chorus 212 on the clean channels. The SC does not have
a preamp in jack but has a power amp in. Is that doable with one of these high voltage pedals like the
Seymour Duncan SFX-03 Twin Tube pedal, so I can by pass the combo's preamp? Would bypassing the amps pre amp with one of these tube pedals make much difference?

Will a pedal like this give one of the SS amps a more tube tone for clean and overdrive? I just debating it makes enough difference to justify spending a couple hundred to get one of these.

Thanks

[DrGonz78]

My immediate response to the question is No. Pick an amp that sounds good in the clean channel. You might not like the dirty channel but at least you like the clean channel. So, now you have some hope of making it sound good. Now take that "good" sound and overdrive w/ a pedal like the Tube Screamer. If that is too tame then yeah the tube pedals can be useful, but you'll need to think about adding in a noise suppressor to really control the gain. I have jammed w/ some of the tube distortion pedals (Tonebone) and it is very colorful sounding. However, it introduces tons of noise on the floor of your signal. So, at loud volumes it rocks nice and loud, but at low volume signals it is overshadowed by a hissing noise.

The original question is that a simple pre-amp tube pedal will make it sound like a tube amp... Well no, definitely No. If you have a tube output that's one thing and that is where it matters most. Think for a minute about "valvestate" and what that means... It is putting a preamp tube in the preamp, just like the Marshall AVT 275, but using only SS technology (transistor) for the output of your signal. So, yeah experiment w/ the preamp in/power amp in technique since you might really like that effect pedal, but have you ever even played through this pedal? It is really a shot in the dark until you try. My bet is that you spend your money on this pedal and it shows up you plug it into the preamp/power amp in and it sounds almost identical to plugging it in to the main input. When it says "preamp in" do you really think your bypassing the amps preamp...? It may say power amp in so maybe it will completely bypass the preamp but I am not sure >>> I may not know completely here so hopefully someone will chime in on that one. However, to me it seems that bypassing the input of the guitar amp only puts it directly into the preamp w/ out any colorization of the treble, mid, or bass pots. To me that is relying completely on a pedal to act as the main tone of amp. Now if you know this pedal then it is not such a shot in the dark. I have tried to find that distortion sound that I am looking for and the only time I have found it was on Marshall JCM2000 head running into a half stack.

Like I said before find an amp that you like (at least clean channel) and then try to use pedals in a way that pushes that sound. Try to use noise suppressor w/ the tube preamp distortion pedals and place a tube screamer or basic booster pedal to click on for those moments that you need to solo. Make it as transparent as possible but experiment to find what you are looking for...

[DrGonz78]

Looking at a few other threads on this situation it occurs to me now that if it says power amp in then you are bypassing the preamp. So go figure right...? lol Anyway when it says preamp in I have no clue if that is another way to say power amp in...?

The main thing here is that you might need to increase line level signal even w/ your high voltage tube preamp pedal. My guess is to use a clean booster pedal and add around 6db to 12db of gain to the signal, but that is just a guess.

Edit: Last thought
If you find an old Music Man combo amp and place nearly any basic distortion pedal in front of it... Well that sounds really cool and those solid state amps sound amazing. Just my last thought before I go pass out lol.

[JimDep]

I only have a short time to post, but thanks for all that common sense detail. I do like the cleans already on both amps. The PV Stereo Chorus has tons of clean headroom, but the clean sound itself has no real character, to it tends to work well with pedals. What I'm hoping for is that the tube preamp pedal would give it a tube quality character for the cleans, and more of a tube tone on the overdrive, rather than the 2 channels of overdrive the amp already has, which sound a little harsh to my ears.
The Marshall AVT 275 has a wonderful clean channel, but neither of the OD channels are very auidable, do to a chip somewhere, I believe needs to be replaced. If I can stay on the clean channel for now with the tube preamp pedal, I'm hoping to get more tube like tonal character over what it has now.
Thanks

[Mark Hammer]

Not to suggest that they are neatly divisible, but there is power-stage distortion from tube amps, and preamp stage distortion. If a person has a Master Volume-equipped amp, and loves the sound they get from diming the front end at modest volumes, then they clearly have a love for tube preamp distortion. Not that they dislike the other type, but that preamp stuff appeals to them enough. If one has a non-master-volume tube amp and, to their ears, the real magic only starts to happen when they turn up the loud or push the amp hard, then they clearly have an affinity for power-stage distortion.

A tube preamp will not usually mimic power-stage properties very well (though I won't say "never"). So if a person has a strong liking of power-stage clipping, then a tube preamp into a SS power stage won't nail what you're aiming for. It won't necesarily sound bad, but it won't capture what some folks value about a tube amp.

[Zipslack]

I may be reading this wrong, but it seems like to you just want to "shape" the basic clean amp sound and make it more "tubey". If this is your intention, then "Yes", try a tube preamp pedal. I have a 20-year old Fender Deluxe 85 US-made SS amp that always seemed a little "sterile" on the clean channel. Adding a Matsumin Valvecaster makes it sound much better (to me, anyway) and works even better in the effects loop. Warning! - tube terms and other assorted crap ahead -- to me, it seems to "warm up" the sound and add more "body" and "definition". This is also a cheap way to check it out and see if it makes you happy.

[JimDep]

I just reread my post and..... I shouldn't post when I'm in a hurry.

Mark; nice explanation and clarifying the difference between preamp and power amp tube distortion. Expecting power amp distortion type tube distortion from a dimed non-master volume amp
wouldn't be realistic if the amp's power amp is SS. So settling for a tube preamp would be a plus over total SS, which makes sense. I'm looking for long sustain on the clean channel of
a single note without heavey distortion...I could try a compressor, but I don't want the tone to be too compressed sounding.

Zipslack; You read it right. I do want to reduce the sterile-ness of the clean channel, especially on the PV Stereo Chorus. The Marshall AVT doesn't sound sterile to me, but increasing the gain
for distortion doesn't knock me out, but it's not bad. I'd like to improve it. I try to avoid those subjective marketing terms such as "warm" "body" and definition too, but I end up with
words that aren't any better, but ya, that's what I'm looking for and I'm agreeing now that there's only one way to find out.

[Zipslack]

Okay, glad to see I read you right. You might have seen this before, but if not...

Account Suspended

Hmmm...wonder why that's showing up like that...just click it and it'll go to the thread at diystompboxes.com

It's a fairly simple build and I don't regret building one at all. Works great to make SS less sterile, and works great as a clean or dirty boost for a tube amp. BTW, do NOT try to run it off a 9V battery - life is measured in minutes.

[JimDep]

Thanks Ziplack, that's an interesting design. Maybe it says "Account Suspended" because the 9volt died?....

At first glance, I thought the bottom picture was a fly fishing reel.... once I get some room to spread out I'd enjoy tackeling a project like that. (tacke...get it?)....

[Mark Hammer]

Actually, it says Account Suspended because they cut me off at work.

[Zipslack]

Oooh, bad kid! No coffee break for you!

[JimDep]

Update:

I got the Seymour Duncan Twin Tube SX-03 stomp box / tube preamp and hooked it up through both the clean channel of the Peavey Stereo Chorus 212 and then through the "Power Amp IN" jack on the back of the Peavey. It sounds amazing through the front end and even better through the Power Amp In. Weather it's clean, slightly over driven or on heavey distortion, this amp now sounds like an old Marshall tube amp! The tube sparkly sound is there and the OD sounds tube all the way. If you have your own effects, such as reverb, delay, chorus, then go through the power amp in. If you want to use the onboard effects that the SC 212 comes with, then go through the clean channel. I doubt anyone would want to use the crunch or the lead channels on the Peavey again. This amp has been reborn.

[stokes]

Although I havent tried any of the commercialy made tube effects,I dont feel they can put enough voltage on the plates,I did build 2 tube preamps for a couple of bass players I know to use with their Peavy bass amps and had really good results.I used 6au6 tubes and built them to stay clean with just a volume control.I didnt hav any kind of schem specifically to copy,I just experimented with a basic tube preamp stage and tweaked it till we got the output flat.While I was experimenting I did get some nice distortion and when I got the final desired effect the bass players were very happy with the sound.It really "rounded" the tone and feel of those SS amps and they both said it made it feel like they now had nice,clean tube amps.So,yes,using a tube preamp,can give you good results.The units I built used a small transformer to put about 250 volts on the plate and plugged in in front of the amp.

[Enzo]

I'd have to say it is a matter of how much voltage they want to put there. They can make any voltage they like. The current demands for a couple triodes is tiny, and even from a low voltage transformer, voltage multipliers are simple and they work.

250v on the plate or 250v B+?

And if it is a pedal out front of the amp, they won;t be needing 30v of signal headroom.

[stokes]

Dont recall the exact numbers,but it was between 200 and 250 on the plate.Really built them on the fly.A simple one stage basic with a volume out.Probably started with a 100k plate res and a 1.5k cathode using a decade box and tweaked it till I got an acceptable output level.The second one was a 2 stage using a 12AU7.It was quite a while ago,so I would have to open them up and see what I ended up using as far as exact component values.