Vox Escort Mains/Battery amp power upgrade?

[spacetape]

Hi everyone. This is my first post, so please let me know if I've posted in the wrong forum.

I have an old Vox Escort Mains/Battery amp that yields app. 2.5 watts from one TBA810 op-amp. I've connected it to a Celestion G12H that's considerably louder than the stock 5" speaker, but it's still not loud enough to compete with a 50W tube amp through 1x12", a drummer and a bass player.

My question is: Is it possible to replace the op-amp to gain more output power (15-20W) or is it more complicated than so? I only use mains so battery life is not an issue.

Cheers

[J M Fahey]

Short reasonable answer is no, you can't.

That said, since what you would need to do is to add more power/transformer/supply/heatsinking plus some wiring to what you already have, and you like its sound , the answer is to do so, but outside it.

Leave it as is, including its original speaker, use it as is for practice, and build a powered cabinet (you already built an unpowered one for the 12") to which you add a 50W chipamp, and the corresponding power supply.

You can mount it on a flat sheet of aluminum and use it as a "backplate amp" mounted on the cabinet back, or, if it's open backed, in a small chassis mounted inside it.

You will also need to modify the Vox Escort very lightly by adding an attenuator ( 2 resistors or 1 resistor and 1 pot) and a signal output jack so you can drive your powered cabinet.

The combination is killer sounding and will hang out with the big guys.

You can buy kits or prebuilt amps + supply and power transformer in various places, including the Net.

Lots of LM3886/TDA7204 kits available or if you want to go even beyond, consider this Velleman kit.

DISCRETE POWER AMPLIFIER 200W - K8060 - VELLEMAN KIT

No, it's not "200W" ...but very real 100W into 4 ohms, some 65/70W into 8 ohms .

With your Celestion it will be the same as a Marshall VS8080 or VS100, a Peavey Bandit, a Crate or Laney G80, etc.

FWIW I live in Argentina and have built tons of such powered cabinets for guys with good but small amps, usually tube 5 to 15W , who want "the same but louder".

If you go on with it, feel free to ask for suggestions.

We assume you have some knowledge and experience , that maybe you already built a couple pedals or similar complexity stuff.

Good luck.

PS: post some picture of the cabinet you built, if possible including back and guts.

Edit: and you were lucky, you landed in one of 2 (two) Forums which may help you without nonsense thrown in (the other one being SS Guitar) .

If you were, say, in DIY Audio they would be pestering you suggesting silver and Teflon wiring (no kidding), caps handmade out of beeswax and real (silkworm) silk with silver/gold foil, etc.

And in tube snob forums (most others) they would be burning you at the stake already for even thinking SS and guitar can be even mentioned in the same phrase

EDIT2: tell us where you live, suggestions depend on what you may have available.

[Jazz P Bass]

The schematic, late '70's, shows a 'Slave Output' jack.
That could be utilized to go to another power amplifier.

Not sure if your amp has that jack.

Note: As the schematic does not indicate voltages coming out of the 'Mains' hookup, I will assume 9 volts (same as the series battery).
The most that you can get in output power from the existing TBA810S is 7 watts, If the power supply is bumped up to 16 volts.
So the limit of all of this is, as stated, the power supply.

[Chuck H]

Hi! I have a 2.5W SS battery powered amp and I'd like to mod it so it's "loud enough to compete with a 50W tube amp"

Really?!? I don't expect new members to be up on all aspects of design and limitation but this is REALLY silly. I guess you don't get anything if you don't ask. But let me put it in perspective... Does it really get past the average user/buyer that there's a reason 50W amps cost tremendously more than 2.5W amps? If it was possible with minor changes to turn a 2.5W amp into a 20W amp, don't you suppose manufacturers would be doing it?

If this is a case of having bought what you can afford, and now it's too small, I'm sorry for your dilemma. If you like the sound of this amp and just want it louder then the re-amp option already proposed is the way to go. If you had options but you bought this amp to gig with anyway, someone seriously steered you in the wrong direction.

I'm just a little stunned that this question ever manifested.

[J M Fahey]

FWIW here's a guy upgrading a Fender 15W SS amp to 60/80W (internally mounted) and of course fitting a better speaker which can take it.

Externally the amp looks about the same, although of course it weighs more, there's no way around that (although you might fit a NEO magnet speaker and a Class D power amp with built in SMPS to minimize that).
https://www.youtube.com/watch?v=RmMDY4aE4v4

By the way, he did what we suggest here

[MarkusBass]

Taking into account the size of the amp: The VOX Showroom - Vox Escort Amplifier I don't think that this is possible. You would need to change the speaker, the power amp, the enclosure, the power supply - everything. You can do it but it will be much cheaper to buy another amp.

Mark

[J M Fahey]

Not inside his current amp, of course.

But he already

I've connected it to a Celestion G12H

so he does have another cabinet.

I suggested he turns that into a powered cabinet, which then can be driven by anything ... including this:



That said, he posted yesterday, checked 1 hour later, found no answers and left forever, probably disappointed with the lack of response.

I answered 30 minutes later, which is unacceptable.

Oh well .