Rackmount tube pres that break up

[parker_knoll]

Hi all

 

I've been running Ampeg SVT 4 and the related SVP Pro for a long time, both for guitars and basses, primarily in recording. 

 

BUT I can't get the SVT/P pre to break up, even with the gain on full using passive pickups. Yes, the SVP Pro has a "Drive" knob but honestly it sounds crappy and I suspect it's just diode clipping. I'm looking for natural tube clipping. I get annoyed using dirt pedals because they always fundamentally change the tonality of the sound. 

 

Are there rack tube pres that will break up a bit? I'm not looking for much, just some crunch. Never had the chance to try a Demeter, TBP-1, Aguilar etc. so I'm looking for recommendations. 

 

Thanks 

Edited 18 hours ago by parker_knoll

[ghostwheel]

That kind of distortion you are after is the power amp distortion, or at least, that of phase inverter. It's impossible to get such one with preamp. You might like to give Origin Effects BassRIG Super Vintage a try.

[parker_knoll]

15 minutes ago, ghostwheel said:

That kind of distortion you are after is the power amp distortion, or at least, that of phase inverter. It's impossible to get such one with preamp. You might like to give Origin Effects BassRIG Super Vintage a try.

i disagree. I have a lot of guitar pres (and full amps) that deliver a very nice bit of clipping with preamp tubes alone. Ever tried an Orange AD30? But sadly most of the guitar pres are all oriented towards high gain applications. I have a few of them. 

 

The answer may lie in a tube pre aimed at mics so I'm busy researching those too (although they can be very expensive). I'm running into a mixer so the tone control section is not crucial, although I love the SVT tone shaping versatility

Edited 18 hours ago by parker_knoll

[three]

1 hour ago, parker_knoll said:

Never had the chance to try a Demeter, TBP-1, Aguilar etc.

 

The Agi DB680 doesn't break up - it's surprisingly clean, and surprisingly tame (IMO) in comparison with the pre in a DB750.  Great for fine sculpting but not for grit or break-up in my experience.  The Millennia TD-1 (half rack I think) doesn't break-up either. 

Edited 17 hours ago by three

[Bill Fitzmaurice]

2 hours ago, parker_knoll said:

i disagree. I have a lot of guitar pres (and full amps) that deliver a very nice bit of clipping with preamp tubes alone.

If that's with guitar amps the speakers are contributing to that clipping, by virtue of the short xmax and break up modes of guitar drivers.

Edited 15 hours ago by Bill Fitzmaurice

[parker_knoll]

5 hours ago, Bill Fitzmaurice said:

If that's with guitar amps the speakers are contributing to that clipping, by virtue of the short xmax and break up modes of guitar drivers.

no, these are PRES. No speakers involved. They distort into a hifi, or straight into the computer, tape deck or whatever. 

 

It's very possible to get breakup from preamp tubes. You just cascade the gain stages to overload the valves. It's how nearly all modern guitar amps work - the ones with a gain and master control. So you can distort at low volumes, LONG before any speaker distortion might come in. 

 

Please don't tell me I don't know what I'm talking about. I do.  

 

Anyone tried the Peavey TB Raxx? Fender TBP-1 has a specific tube overdrive section but i can't find one anywhere. 

Edited 10 hours ago by parker_knoll

[paul_5]

 

9 hours ago, parker_knoll said:

BUT I can't get the SVT/P pre to break up, even with the gain on full using passive pickups. Yes, the SVP Pro has a "Drive" knob but honestly it sounds crappy and I suspect it's just diode clipping.

 

Thanks 

The SVP won't break up as it's not designed to. The SVP PRO will add valve drive by pushing a 12AU7 into overdrive, but it's not just diode clipping.

 

10001c1_.pdf

 

Page 2 shows the arrangement and use of the 5 preamp tubes - V4 is the 12AU7 responsible for the 'drive' circuit. It can sound a bit 'fizzy' when running direct to a desk, but through a power amp and an 8x10 it's glorious.

 

Edited 9 hours ago by paul_5

[Mykesbass]

7 hours ago, parker_knoll said:

 

Please don't tell me I don't know what I'm talking about. I do.  

 

 

So why ask the question? 

[Ed_S]

7 hours ago, parker_knoll said:

Anyone tried the Peavey TB Raxx?

 

I used to have one. Sounded pretty good into a Classic 60 power amp and cabs, but there wasn't very much pleasing about the tone straight out of the back and into a mixer. It was easy enough to overdrive, though, so you might like it if you put some decent speaker emulation after it; I ran it into a Torpedo C.A.B. for a while, but ultimately it wasn't worth the effort and expense to make it sound good compared to my usual SansAmp RBI / RPM / VT-RM. I seem to recall reading that the TG Raxx is internally identical to the TB, which might hint at why there's guitar level gain on a bass preamp, and also makes it easier to find one to try since either unit should suffice.

[parker_knoll]

8 hours ago, paul_5 said:

 

The SVP won't break up as it's not designed to. The SVP PRO will add valve drive by pushing a 12AU7 into overdrive, but it's not just diode clipping.

 

10001c1_.pdf 211.47 kB · 0 downloads

 

Page 2 shows the arrangement and use of the 5 preamp tubes - V4 is the 12AU7 responsible for the 'drive' circuit. It can sound a bit 'fizzy' when running direct to a desk, but through a power amp and an 8x10 it's glorious.

 

 

Ah, sadly I sold mine but mainly because it was noisy. They're pretty rare

[parker_knoll]

3 hours ago, Mykesbass said:

So why ask the question? 

I want recommendations for tube pres that breakup. I can name you three right now but sadly i've never tried any of them. Overdriving the preamp tubes is the most common way to create distortion in tube amps these days and usually sounds good. See paul_5's response above on the how the SVP Pro's distortion circuit works. 

 

Saying "It's impossible to get distortion with a preamp" a) is wrong, b) doesn't answer the question, and c) is annoying because it implies the questioner doesn't know what they're talking about. 

I'm just looking for a bit of crunch, not Steve Vai, but tube crunch > tranny crunch in my opinion and it means your crunch sound is consistent with your clean sound. 

Edited 1 hour ago by parker_knoll