Turning a valve preamp circuit into a standalone preamp?

[swansongrecords]

Bear with me chaps...

To cut a bit of a long story short, I play in a band which is very hot on its authentic equipment. The backline has to look right (and of course sound right). This is entirely wonderful but i'm the one that has to carry the Ampeg V4 and 2x15. I'd like to save my vintage gear and my back.

What I'd like to do is build myself a much lighter 'fake' setup as it were. I'd like to build a preamp and power amp section into a head cab that looks the part but weighs a lot less and packs a bigger punch. Im not worried about cabs for now, theres a lot of info out there about that.

Any idea how I could potentially achieve this? Im afraid im not that clued up on the modern bass setup, as i've always used vintage gear. I don't need it to be anything complicated, that said If i could replicate a superbass/ampeg/sunn preamp of the late 60s and have it run into a simple standalone power amp section, that would be perfect. 

Sorry if that sounds like madness, but someone might understand where im going!

Thanks in advance.

[Bridgehouse]

If someone made a box with a b15 or SVT preamp section in it and a DI out I’d be round there with my readies out quicker than billy whizz

[Bill Fitzmaurice]

1 hour ago, swansongrecords said:

 If i could replicate a superbass/ampeg/sunn preamp of the late 60s and have it run into a simple standalone power amp section, that would be perfect.

Maybe, maybe not. At least half of what makes a valve amp sound like a valve amp is the valve power amp. Even emulators don't get it quite right, that's why valve amps still exist.

[cattytown]

If you can get close enough with a modern amp to the sound, why not do that, just hide it behind a fake amp? some of the old amps of that era looked remarkably DIY. 
You could build a fake head cabinet, basic ally sheet panel with a few knobs, a little bulb to pretend it's on and away you go.

[BassBod]

Two thoughts.  The Hartle LH500 is essentially an old “Fender” preamp mated to a late 70’s style power amp. Not expensive, but worth a try.  If it does the job put some vintage knobs on it and put it in an old style case. 

 

Or - get a powered cab, dress it up, and use a Sansamp VT for your sound (stage and DI for the PA).  

Both could work very well. 

[Jus Lukin]

-

Edited March 1, 2022 by Jus Lukin

[jrixn1]

Do you need one of these, or similar?
i.e. a modern amp but doesn't look modern.

Markbass CASA

Fender Bassman 500

Music Man BH 500
 

[swansongrecords]

4 hours ago, BassBod said:

Two thoughts.  The Hartle LH500 is essentially an old “Fender” preamp mated to a late 70’s style power amp. Not expensive, but worth a try.  If it does the job put some vintage knobs on it and put it in an old style case. 

 

Or - get a powered cab, dress it up, and use a Sansamp VT for your sound (stage and DI for the PA).  

Both could work very well. 

Thanks for all the replies so far, they’re most helpful!

This is the sort of thing that would be most useful. It doesn’t have to be spot on authentic it just has to look and sound right. The sort of sound I’m aiming at is an overdriven superbass a-la Jack Bruce, I can build a head cab that’s good enough to fool most people, I just need to work out a way of sorting the ‘innards’ out as it were. I’m quite happy to build a pre if I need to and can’t buy what I’m after.

i suppose what I really mean now is what preamp and power amp can I hide in a fake vintage head cab?

I could also rehouse a stand alone head, always open to ideas, as said, I’m not that familiar with the market so your input is most appreciated.

Thanks again 

 

 

[Cuzzie]

I reckon What ever pedals or power amp give you your sound, hide it inside a shell of an old amp head completely gutted.

You don’t even need to bolt it in the box making it easy to carry all parts separately for any occasions.

If you use wireless, sorted, if you don’t, no one will notice if it is going in the front or round the back.

Loads of bands used empty speaker cans for it to look like they had a million 8x10s

No different

[BassBod]

LH 500 would be easy - it’s a standard 2u rack size...just take off the Hartke logo and bolt into any retro style case 😎.  It will probably drive nicely, but you’ll need a high input level to make it growl (really designed for clean, but it’s a 12ax7 valve pre in the front)

[Cuzzie]

Get the LH1000

Even more power, not too dissimilar second hand prices, can be gotten for under £200 - I loved that amp

[Jack]

I think the issue with putting a class D amp in a bog wooden box is that, whilst lots of the weight in a head is the transformer, the psu, etc etc, LOTS of the weight is actually the wooden shell. I wonder if all the effort would be worth it.

 

Do you reckon that just a (period-correct) cab would look ok for backline? Like, do you need a head? I bet most people couldn't tell. What about like hiding a modern head behind the cab where no one could see it and then using something like a sansamp? For that matter, how feasible is adding a plate amp to your current cab? That way you can just use a pedal preamp and no one would be any the wiser IMO.

 

EDIT - Or this.

Edited July 17, 2018 by Jack

[jezzaboy]

It`s a pity that the Behringher, Ampeg clone (bvt 4500) that was kicking about Thomman a while back isn`t available now for the crazy price it was. You could have stuck a power amp and pre in there no problem as the bottom section was empty and it looked like a Ampeg SVT.  There are a few threads on it on this forum. I had one and sold it for £50. I should have kept a hold of it on reflection.

[swansongrecords]

4 hours ago, Jack said:

I think the issue with putting a class D amp in a bog wooden box is that, whilst lots of the weight in a head is the transformer, the psu, etc etc, LOTS of the weight is actually the wooden shell. I wonder if all the effort would be worth it.

 

Do you reckon that just a (period-correct) cab would look ok for backline? Like, do you need a head? I bet most people couldn't tell. What about like hiding a modern head behind the cab where no one could see it and then using something like a sansamp? For that matter, how feasible is adding a plate amp to your current cab? That way you can just use a pedal preamp and no one would be any the wiser IMO.

 

EDIT - Or this.

A head is a given I think to be honest. It’s not weight in itself that’s the issue, it’s that plus the rarity of the head, difficulty of replacing it if it’s stolen, servicing etc. It’s an original V4 and it’s wonderful but if it’s nicked I may never find another one.

its sounding like reboxing a head is the answer, if I can get a big box Marshall head cab and make a new faceplate for an amp of choice then I think that’s the ticket. So far the Hartke is winning but open to suggestions for superbass tone-age. Although ‘tube DI’ is not a stupid idea for super lightweight touring ability I must say.

 

You’ve all been top so far, thanks 

[Cuzzie]

For a tube DI, pretty sure I saw a Khan for sale on here a couple days ago, there is of course a REDDI as well

[pete.young]

1 hour ago, Cuzzie said:

For a tube DI, pretty sure I saw a Khan for sale on here a couple days ago, there is of course a REDDI as well

I have a Dave Hall VT1 Pro which is great.

[Jack]

13 hours ago, swansongrecords said:

A head is a given I think to be honest. It’s not weight in itself that’s the issue, it’s that plus the rarity of the head, difficulty of replacing it if it’s stolen, servicing etc. It’s an original V4 and it’s wonderful but if it’s nicked I may never find another one.

its sounding like reboxing a head is the answer, if I can get a big box Marshall head cab and make a new faceplate for an amp of choice then I think that’s the ticket. So far the Hartke is winning but open to suggestions for superbass tone-age. Although ‘tube DI’ is not a stupid idea for super lightweight touring ability I must say.

 

You’ve all been top so far, thanks 

Ok, that makes sense. It does seem as though many of the mods being talked about here are permanent or at least very involved to put back. Gutting the old amp seems like a viable choice, or even making a fake one from scratch. But rather than ruining a perfectly nice micro amp by modding it into an old shell, I'd still be tempted to hide the new amp behind the cab and just set the old one up on top. That way the new head at least remains unmolested and re-sellable.

 

Left field. Make a 4U rack from wood and cover it in tolex to match your cab. Get preamp , tuner and poweramp of choice*. Rather than a front rack door, use grille cloth with the same logo as your cab.

 

*GED2112, Korg Pichblack, QSC Powerlight. 🙂

[cattytown]

If looking at pre's, there's a Two Notes Le Bass in the marketplace...

P.

[Bigwan]

On 16/07/2018 at 23:44, Bridgehouse said:

If someone made a box with a b15 or SVT preamp section in it and a DI out I’d be round there with my readies out quicker than billy whizz

You mean like this: http://www.arkhamsound.com/abyss.html

[bassmayhem]

What is the most important thing, that it sounds old or looks old?
A friend of mine who plays in a Beatles tribute band use a MarkBass combo with Vox speaker cloth on. Just for appearance. Find yourself a nice sounding "top loaded" combo and change its clothes.

If the sound/tone is a main thing, well, you can always add a nice preamp in front...

Or: get a Peavey VB-2: the most underrated fantastic all valve amp out there. Sells for coffee money...

[prowla]

I thought that Ampeg did a rack-mount preamp and here's one that sold on ebay recently.

https://www.ebay.co.uk/itm/Ampeg-SVP-Pro-Preamp-/113112449571?hash=item1a56070223%3Ag%3Akk8AAOSwD99ayMYj&nma=true&si=NHDiROD4oAAb%2FJ7CV2z5DMB%2BEgw%3D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557

Also, in searching for links to it, I came across this clone...

http://www.frontiernet.net/~jff/SonOfSVPCL/DIYSVTBassPreamplifier.html

Edited July 31, 2018 by prowla

[swansongrecords]

On 30/07/2018 at 11:09, bassmayhem said:

What is the most important thing, that it sounds old or looks old?
A friend of mine who plays in a Beatles tribute band use a MarkBass combo with Vox speaker cloth on. Just for appearance. Find yourself a nice sounding "top loaded" combo and change its clothes.

If the sound/tone is a main thing, well, you can always add a nice preamp in front...

Or: get a Peavey VB-2: the most underrated fantastic all valve amp out there. Sells for coffee money...

 

The sound is the most important bit, i can deal with how it looks as discussed earlier. A VB2 is a fantastic idea, however finding one is another matter, i'll have to keep an eye out.

[bassmayhem]

10 hours ago, swansongrecords said:

 

The sound is the most important bit, i can deal with how it looks as discussed earlier. A VB2 is a fantastic idea, however finding one is another matter, i'll have to keep an eye out.

I had one for sale a while ago, but in Sweden. Customized wih a cabinet in smoked oak...

Sold, I'm afraid...
The little Quilter BassBlock 800 acts very valve-ish compared to other solid state amps. 1.7 kg isn't wrong either. You can attach that one to their own cabinet and cover the front with whatever vintage cloth. I used that amp for everything from acoustic upright to downright metal. Listen to this demo:

 

Edited August 2, 2018 by bassmayhem

[Chimike]

I also love, and play, vintage gear, but due to re- occurring back problems, I have tried to shed some weight. I've found some pics of my earlier attempts. Cases ,( yet to be covered ) are poplar ply, replacing manufacturers boxes made of lead. Pre-amps ( SVT,s ) are Ebay purchases, with added power supplies, built by myself. Power amp to taste, depending on gig, but I've often used a B&O 500 watt module, bought from Bigwan, or  Hypex modules. I've also cloned some speaker cabs in poplar ply, but often the easy way to lose weight is to go for neo's. Certainly work in my Ampeg and Mesa 2 x15's. I'll try to list recent, more finished photo's, when I can work out how to get them off my phone .

[Chimike]

More recent photo!s, showing spare available for power amp. Box in middle pic is Bigwans B & O module.