Valve guitar pedal?

**Franz 1997** · 08-24-2014, 02:20 PM

For anyone who's interested, I've had the 2nd proto version of this valve preamp for a couple of days now.

I first got interested in exploring the preamp/SS amp route again after reading about Jack Z's experiments, so I got Martin @ coopersonic to make me a preamp unit based on the old fender 5E8 tonestack, which is a more middle-based 'tweed' tonestack than the common fender blackface ( AB763) arrangement. As JZ found, the tube preamp configuration gets most of the tube amp feel and touch sensitivity when in front of a good SS amp ( in my case, a mambo 12 combo).

Coopersonics is about to market the preamp, but with a 3 knob blackface tonestack, because it will appeal to more players; many pros use fender BF/SF amps when they can, so it's a popular format and sound.

This later version, which I think may be coopersonic's final design, has the important addition of a 20k wide range mid control, which means in practice that you can get quite a lot of mid content at around the 500hz mark, when turned to max. At lower settings, you have the classic fender sound. Put another way, it can go from fender to ampeg, although not to polytone.

For the technically inclined, how it works is that the signal is put through 4 valve stages, of which 2 are cathode followers, giving asymmetrical 'harmonic distortion'. Translation; it rounds off the edges in the note and produces a very fat, touch sensitive sound, with that valve/tube 3D quality. What this latter is, I'm not sure, but it is unmistakeable- when you hit bypass and just get the SS amp sound with no pre-amping, the SS sound seems flatter and without dynamics by contrast. You don't get any audible distortion ( although you could with a different tube type), just the touch sensitivity and impression of far greater dynamic range, plus the addition of an extra eq stage - in this case, a classic fender format.

For those who can't or won't hump a valve combo around, a preamp like this (plus a good SS combo with a lot of headroom) seems to me to be a very practical/ portable alternative, which gets you most of the way. You don't get power amp distortion of course, but I can live without that.

There are good US alternatives I'm sure, but for anyone this side of the pond the coopersonics preamp is well worth investigating. There may be other european makers, but I'm not aware of them. No affiliation BTW - I paid for mine..
the only downside is that it isn't cheap. But, it's cheaper than a DLR or VLR etc. And, much cheaper than osteopathy.

**lapideusvir** · 08-24-2014, 02:44 PM

Very nice! I´m really interested in the preamp.

**GuyBoden** · 08-24-2014, 04:47 PM

Originally Posted by Franz 1997

For anyone who's interested, I've had the 2nd proto version of this valve preamp for a couple of days now.

I first got interested in exploring the preamp/SS amp route again after reading about Jack Z's experiments, so I got Martin @ coopersonic to make me a preamp unit based on the old fender 5E8 tonestack, which is a more middle-based 'tweed' tonestack than the common fender blackface ( AB763) arrangement. As JZ found, the tube preamp configuration gets most of the tube amp feel and touch sensitivity when in front of a good SS amp ( in my case, a mambo 12 combo).

Coopersonics is about to market the preamp, but with a 3 knob blackface tonestack, because it will appeal to more players; many pros use fender BF/SF amps when they can, so it's a popular format and sound.

This later version, which I think may be coopersonic's final design, has the important addition of a 20k wide range mid control, which means in practice that you can get quite a lot of mid content at around the 500hz mark, when turned to max. At lower settings, you have the classic fender sound. Put another way, it can go from fender to ampeg, although not to polytone.

For the technically inclined, how it works is that the signal is put through 4 valve stages, of which 2 are cathode followers, giving asymmetrical 'harmonic distortion'. Translation; it rounds off the edges in the note and produces a very fat, touch sensitive sound, with that valve/tube 3D quality. What this latter is, I'm not sure, but it is unmistakeable- when you hit bypass and just get the SS amp sound with no pre-amping, the SS sound seems flatter and without dynamics by contrast. You don't get any audible distortion ( although you could with a different tube type), just the touch sensitivity and impression of far greater dynamic range, plus the addition of an extra eq stage - in this case, a classic fender format.

For those who can't or won't hump a valve combo around, a preamp like this (plus a good SS combo with a lot of headroom) seems to me to be a very practical/ portable alternative, which gets you most of the way. You don't get power amp distortion of course, but I can live without that.

There are good US alternatives I'm sure, but for anyone this side of the pond the coopersonics preamp is well worth investigating. There may be other european makers, but I'm not aware of them. No affiliation BTW - I paid for mine..
the only downside is that it isn't cheap. But, it's cheaper than a DLR or VLR etc. And, much cheaper than osteopathy.

Is it similar to this?

Coopersonic ? Deluxe Valve Overdrive

**Franz 1997** · 08-25-2014, 04:47 AM

Yes, in that it's the same small box, and it has the same control titles on the knobs, with different graphics.

No, in that it's not an overdrive or distortion effect, is for jazz guitar, and uses NOS 12AU7s, not 12 AX7s.This one uses 2 cathode followers to massage the signal and give touch sensitivity. It's currently called the Jazz Valve Preamp.

Note- I said I wasn't aware of other Euro makes of valve preamp; it turns out after a little googling that there are many of them, all with different configurations. However, this is the only one I know of that is tailored to jazz guitar - i.e. not a distortion effect, or a mic preamp. Would be interesting to hear of any others.

**lapideusvir** · 08-25-2014, 05:03 AM

<p>

Originally Posted by Franz 1997

it turns out after a little googling that there are many of them, all with different configurations.

Hi, just stumbled across this one: it´s from England and seems to be very high-end stuff... Blackbird Vacuum Tube Preamp | effectrode Has a dirt-channel, ok, but in clean emulates Fender BF.</p>

**lapideusvir** · 08-25-2014, 07:01 AM

Originally Posted by Franz 1997

Not quite; his clean channel just uses 1 12AX7, not 2 x 12AU7,

Yes, but it seems that with the "blackbird" you have the ability to try different tubes in it. You have bias adjustments to do so. But ... as I see, this is only possible for the overdrive channel!?

**Franz 1997** · 08-25-2014, 08:04 AM

Originally Posted by lapideusvir

... as I see, this is only possible for the overdrive channel!?

That's how I interpreted it, from the website. That's why I think it is more of an overdrive device.

**lapideusvir** · 08-25-2014, 10:54 AM

You are right, Franz. Its nice to have a second channel for real tube-od, but the clean-channel should be more sophisticated/tweakable. The product seems to aim at the guitarists who like to crank up and rock ... that was and is the majority of them...

**Greentone** · 08-25-2014, 10:46 PM

I have designed and built tube musical instrument circuits for 40 years. There is nothing wrong with the circuit above--except the voltage. That is, if you are interested in CLEAN tones. Running triodes at voltages such as those supplied by a battery, when those tubes were designed to be operated efficiently at over 100-volts DC, is a terrific recipe for developing a distortion signature--which is what the designers had in mind, i.e., to build a tube-based "snot" pedal.

Now, jazz has a very broad tonal palette. There is great room for a distorted sound. However, if what you are seeking is some sort of mainstream guitar tone, my advice would be to skip the pedal altogether and just play straight into the old Roland Cube. It delivers an adequately warm sound. In fact--and I say this as someone who has built MANY all tube amps--there exist quite a few solid-state amplifiers that deliver a fine, warm jazz guitar sound. The Cube is one, but there are others. The old Polytone amps do the job well--they are simply NOT clean, sterile amps.

The sound of the Evans Jazz Amp is also a solid-state design that gets the job done. Gibson's old Lab Series line from the 70s, though big, heavy, etc., is a warm, gritty solid state design that provides great jazz tone.

If you just plug into a Cube, I think you will be well pleased. If you want to scruff it up, however, try your tube pedal.

**Franz 1997** · 08-26-2014, 04:50 AM

Originally Posted by Greentone

I have designed and built tube musical instrument circuits for 40 years. There is nothing wrong with the circuit above--except the voltage. That is, if you are interested in CLEAN tones. Running triodes at voltages such as those supplied by a battery, when those tubes were designed to be operated efficiently at over 100-volts DC, is a terrific recipe for developing a distortion signature--which is what the designers had in mind, i.e., to build a tube-based "snot" pedal.

Might be some misunderstanding here. All the preamps under discussion are running @ anode voltages of 200-300 vdc.
The 12v dc input is internally converted to conventional tube anode voltages these days - don't think anyone's talking about batteries. Most modern preamps use this technology. As an experience amp builder, you'll know already how cascaded dc and ac coupled cathode follower stages can produce asymmetrically 'flattened' sine waves and 2nd harmonic enrichment without audible distortion. That's the circuit I'm describing.

It produces touch sensitivity and the impression ( whether real or illusory) of greater dynamic range and presence. Evans, Mambo and Poly amps do a great job, and are far from sterile-sounding, but adding a tube preamp running at high voltage adds something else to the mix which they can't provide IMO. No experience of Lab or cube amps.

**Greentone** · 08-26-2014, 07:02 AM

I missed the conversion. Those voltages will work.

**krueger** · 08-27-2014, 02:10 AM

Another series of high-voltage tube pedals are the HT line from Blackstar (12ax7 runs at 300V). I have a HT-Dual which has two channels, where the first has a clean/crunch mode. I tried it on the clean setting yesterday with my telecaster and it stays clean to about 50-60% up on the gain knob with the neck pickup. Tone shaping (bass,middle,treble) has a wide range. It also has something called isf which allows you to change the character of the voicing from an American (Mesa-like?) to a British (Marshall), which mostly affects the midrange response I think. Another feature on this particular model is that it has two outputs one normal jack and one compensated for recording.

It was a quick test but I thought it sounded good clean. It kicks butt on the crunch and lead settings also if you're into that...

**lapideusvir** · 08-28-2014, 06:08 AM

Here is another interesting preamp-maker from France. Website is a bit strange, but they offer interesting preamp-pedals. Look at the "Crystal Preamp" or "The Clean".
FredAmp - FredAmp Custom Amplification - Home

**Franz 1997** · 08-28-2014, 06:14 AM

Thanks - interesting site.

**niftyprose** · 09-12-2014, 07:12 PM

Hi guys,

Had e-mail from Martin at Coopersonics, who are putting out an interesting valve preamp pedal specifically for jazzers which has been referenced on this thread. Here's the note.

Best, W.

_____

Hi,

Just to let you know that our Jazz preamp pedal is done, and will be ready to ship next week.

It's called the Coopersonic Jazzbox...

Some details - 5 knobs, drive, volume, bass, treble and mid; it has an AB763 type tonestack, and is fitted with 2x NOS American 12AU7 valves running at high voltage. Plenty of level boost available, very clean, though with drive at max it will just start to give a little breakup with louder guitars. Footswitch true bypass, LED indicator, though you might want to keep it on all the time...

Power is provided by a universal power adapter with an IEC mains inlet which will work on 90-250V AC. An IEC mains cable is supplied for UK/EU customers. Power requirements are 12Vdc 500mA, centre positive 2.1mm plug. It might be possible to run it off certain "power brick" type supplies but obviously we can't test them all. They would need to be able to supply at least 500mA of well regulated dc and would probably need a polarity reversing cable and/or a parallel cable for using two power outputs at once. If in doubt please ask.

Size is approx 140x90x50mm; power supply 95x45x35mm. Photo below.

They are not on the website or eBay yet, but will be soon. Price will be £250 plus shipping, but if you were wanting to get one before general release then I can do them for a limited time for £225 plus shipping. Let me know if you're interested, or if you want to know anything else.

All the best,

Martin

Coopersonic Pedals

**lapideusvir** · 09-13-2014, 10:03 AM

Will try it soon...

**lapideusvir** · 09-21-2014, 08:54 AM

My personal impression: doesnt do the trick for me at all. The pedal does just add a tiny bit of sound (sensivity). In a blind test, I wasnt even able to tell whether it was on or not. (but this is just my humble opinion/impression)
My first Valve Preamp so far. No comparison to others but I will try FredAmp Pedals or the Kingsley Squire.

**Frank67** · 09-21-2014, 10:26 AM

Did you run into a valve poweramp? A preamp into another preamp may not cut it. Please keep us posted about your exploration!

**lapideusvir** · 09-21-2014, 10:35 AM

No, I ran it into a ss-amp.

**Drifter** · 09-21-2014, 11:54 AM

Soundwork from Austria is worth a look. I only know the Real Drive, a mild tube overdrive that certainly adds the tube liveliness the OP is looking for. When used with low output pickups, it won't even distort in the highest setting, that's how mild the overdrive is. But you will get the increased presence, sparkly treble and dynamic attack associated with tubes. I've used it with a Fender Jazz King years ago and it definitely added tube feel and tone to the solid state amp.

Soundwork

**unguitar** · 09-21-2014, 02:32 PM

Originally Posted by lapideusvir

Here is another interesting preamp-maker from France. Website is a bit strange, but they offer interesting preamp-pedals. Look at the "Crystal Preamp" or "The Clean". FredAmp - FredAmp Custom Amplification - Home

yes, interesting. But what a bad attitude to people looking for informations ! No info on the website and very bad youtube videos.

**unguitar** · 09-21-2014, 05:46 PM

Oh, about the Blackbird someone has mentioned earlier.
I had it and preferred to keep my Ethos instead.
The Blackbird ( which has a very nice saturated channel) didn't convince me on the clean one.
It sounded glassy, with a dominant upper mids peak which stayed with any eq setting you could tweak and even changing its tubes.
I was expecting that kind of crispiness in the highs that I can always find in the good tube preamps.
My reference are the Mesa Boogie Studio and the Alembic preamps.
The Studio is my favourite for a clean tone gently breaking up at the top.

**jorgemg1984** · 09-21-2014, 08:04 PM

If you don't like the Blackvird try the Barb EQ. Been using it with a good cab sim trough a PA cab and sounds scary close to the true blackface I play sometimes.

**jorgemg1984** · 01-05-2015, 08:30 PM

I am still considering getting one of these... my barbq has been long term loan from a student and needs to return home soon. Anyone compared the Coppersonic Jazzbox to the Kingsley Squire? The Kingsley is quite cheaper and has 3 different sounds but only 1 tube vs 2 tubes on the Coppersonic.

**lapideusvir** · 01-06-2015, 05:28 AM

To me, the Coopersonic was a bit of a dissapointment, I was expecting more... but maybe its me who doesnt care much of a "valve sound". Maybe I´m just fine with the polytonish thing (as a Mambo owner). I always wanted to try the Squire but I´m in Europe and I dont want to carry the expenses in case I have to sent it back. The Crystal by Fred-Amp is also very interesting and gets good reviews. Build in France.
FredAmp - Crystal Preamp

btw. the Squire dosnt have a master-poti, has it?