Guitar amplifier Acoustics Torque 12

[julio daniel]

Hello everyone
This is my first post and I am in need of help, to make some changes to an Acoustics Torque 12 amplifier, I need the diagram. I've already made some changes such as: I changed the original 8 "speaker to a 10" Celestion Tube 10, I replaced the TDA2030 output chip with a TDA 2050, I intend to include a MOD 8EB2C1B reverb line, the driver for this line already it is built and tested, all that remains is to reach the line that is already ordered.
In addition to the scheme I am open to all suggestions.
My thanks in advance.
Best regards

J.D.

[julio daniel]

Hello
To identify the Torque 12 amplifier, I add some photos, the speaker you see, is already the Celastion tube 10.
best regards

[joecool85]

If you could get us some better pictures that would help a lot - the one you posted is quite fuzzy.  Not sure we'll be able to find the schematic as this isn't an amp I'm familiar with.  If you can get us a couple pictures of the PCB (top and bottom), we maybe be able to help you figure out what you need anyway.

Regardless, welcome, and good luck with your project!

[julio daniel]

hello, good morning
by the time here.
Thank you for your answer Joecool85, the amplifier is quite simple: 1st stage with a TL072, between the operational ones, there is a limiter / compressor made up of two BC182 transistors and two 1N4148 diodes, for some cut, then and after the second of the TL072, is the tone control, only with bass and treble and very simple, the tone control output directly attacks the output amplifier in the case of a TDA2050, which is not original, originally had the TDA2030, the power is consisting of a transformer with symmetrical 13.7 volt outputs, rectifier bridge and 2200 micro farad filter capacitors, the whole set is very simple. My goal is to add a reverb line and maybe in the near future change the power transformer, for a higher voltage, in the 2x17 volt range, which would allow to get about 30watts in the output, which is the reference power of the loudspeaker that I have installed a Celestion Tube10, which I recovered from a ZOOM amplifier, after it was replaced by EMINENCE of 75 w.
greetings
J.D.

[dmeek]

I can draw a schematic of this board if you take another photo of the component side with the heatsink removed and another photo of the foil side with the white material removed
And if you can clean the foil side with solvent and an old toothbrush or whatever, it would help

[joecool85]

Any reason you replaced the TDA2030 with a TDA2050?  At the voltages you are running you won't see any gain there.

**EDIT**
I was wrong, you do pick up a couple watts with the swap, assuming that your PSU can supply the amperage required.

[Enzo]

On the other hand, if you double the power output you only gain 3db.

Just asking, why would the 2050 increase power out?  The power supply doesn't increase.  can the 2050 drive closer to the rails or something?

[joecool85]

On the other hand, if you double the power output you only gain 3db.

Just asking, why would the 2050 increase power out?  The power supply doesn't increase.  can the 2050 drive closer to the rails or something?

I believe that is the case.  Not 100% sure, all I know is that based on the datasheet for the 2030 and the datasheet for the 2050, at +/- 13.7v, the 2050 will put out a few more watts (I think it was 2.5watts more or so).

[phatt]

Hey Joe,
 yeah but the Pwr Tx can't deliver any extra *Current* so no extra wattage is delivered by using a more powerful chip.
Phil.

[julio daniel]

Hello everyone
I will try to reply to your posts.
Finally and after a long time, I found encouragement there to remove the amplifier's scheme, because because of confinement (covid-19), we have to occupy time, otherwise we go crazy.
The scheme is already on the question of using the TDA2050, as I mentioned in a previous post, this aims in the medium term to replace the transformer with a more powerful one with an AC voltage output between 17 and 17.5 Volts. On the other hand, even using the current transformer, the TDAxxxx circuits, available on the market, are not original, since the manufacturer considers them obsolete.
Thanks to everyone, suggestions are accepted to optimize the existing circuit, if possible.
Greetings.

J.D.

P.S. The driver scheme for the tank reverb is just to complement, as this circuit is already built and tested, I just need the MOD line 8EB2C1B, which should arrive on Monday

[dmeek]

Re-check the transistor area. something is wrong.

[joecool85]

Hey Joe,
 yeah but the Pwr Tx can't deliver any extra *Current* so no extra wattage is delivered by using a more powerful chip.
Phil.

While we don't know this for sure, you are probably right as most times manufactures use transformers that are *just* big enough to begin with.  It's possible that the amp is now exhibiting PSU voltage sag.

[julio daniel]

Hello everyone
in particular I respond to the observation of the dmeek, in fact the diagram had inaccuracies, the annex follows the corrected version, and also a detailed version of the transistores part.
I think I will try to reformulate this preamp, keeping the rest of the components, I have plenty of time, so I will start to elaborate a new board with a new circuit, even if it is limited by the amplifier panel.
Greetings.

[dmeek]

Hi Julio

Can you post some better photos of the circuit board, both sides?

[julio daniel]

Hello everyone
I will try to answer the dmeek's comment, but the photos, although sharper, are limited to my Samsung camera, which is not the best.
best regards