PUNCH - 1W amplifier

[tca]

Just found chromesphere's youtube PUNCH video. Very nice!

https://www.youtube.com/watch?v=TPckPDHDAMM

Cheers.

[chromesphere]

Thanks TCA!

The TDA7052A has gone obsolete but I've bought a few...ahem...well, 100, and put them on my store for anyone wanting to build this kick ass amp!

Cheers
Paul

[DefiantAudio]

Just ebay'd a handful of tda7052a chips. I can't wait to try and put one of these nifty little amps together.
Thanks to the powers of youtube and chromesphere to making me want to build one of these bad boys.

[DefiantAudio]

I increased the coupling cap from 470nf to 1uf.  There wasn't much difference unfortunately.  The freq response still sounds kind of dull.  I think what I might be after is a treble boost.  With my 7 band eq pedal infront of it, slowly rolling up the last 4 bands, the output sounds much nicer to my ears.  I think this is just how the tda7052a sounds.  I think it just sounds like your guitar signal. Im just used to boosting treble on my amps!
Paul

Couldn't you add like a TMB tone stack to the circuit to compensate?

[chromesphere]

I should also mention I have PCB's for this project as well.  They will fit into a 1590a and I've added pads for LED and on/off switch.  The explanation for the headphone jack wiring is explained in the videos (for those following along):

http://www.diyguitarpedals.com.au/shop/index.php?main_page=product_info&cPath=1&products_id=84

@defiantaudio - Thanks for the compliment!  As far as the tone issues go, it was more a problem with my (lack of) understanding as to what the circuit actually does.  It's basically like setting your guitar amp at home to zero on all the tone dials (flat response).  You'd need a tonestack that increases frequencies and not just cuts them.

[tca]

Couldn't you add like a TMB tone stack to the circuit to compensate?

You could add tone control width a mid scope, e.g.,  BMP tone control, that would do the trick. Don't forget to add, also, a high impedance booster to boost the signal up.

buffer -> BMP tone control -> booster -> TDA7052

or

booster -> BMP tone control -> buffer -> TDA7052

Cheers.

[DefiantAudio]

@chromesphere Possibly add one of your 7 minute boost circuits before the amp circuit?
I'm still fairly new to the whole pedal building (my first build was a breadboarded 7 min fuzz. You've been my go-to guy on youtube for building effects up to this point ha) and in the veeeeerrrrry early stages of an EE degree, so I apologize for my ignorance.

[seadi123]

Paul (chromesphere) has also been my "push" for getting into DIY effects . Tayda didn't have the chip for the punch amp so i had to buy it on ebay , and it finally arrived ! Tomorrow i'll build this amp in a Altoid Tin , and i'll post a video here . Cheers

[chromesphere]

Thanks guys!
Yeah you could use the 10 min boost for it, it doesn't have an insane amount of boost but probably, 3-4x volume on your signal.  Plus you can use the switch to dirty it up as well 
Don't worry about sacristy of the chip, I've invested in the future of this project
Paul

[MaxPower]

Since Mouser didn't have any TDA7052s I ended up building a 1-2 watt amp using an NJM2073D. Don't know how it compares to Punch as far as sonic quality goes but it's good enough for me. Especially since I built it for when there's a power outage (which happens all too often) and I feel like playing.

[EVAD]

Heres another TDA7052 1W Amplifier





http://www.circuitspecialists.com/kit-27.html

[tca]

^ That version has a very low input impedance to be used has a guitar amplifier, but with a buffer/booster(high impedance) in front of it it works great.

Cheers.

[DefiantAudio]

For the sake of making a small tube-ish amp by adding a valvecaster or equivalent circuit to this amp, are there any changes necessary or just run the out of the valve into the amp? Or possibly put the amp before the valve? I ask because I have bunch of 12au7s sitting here and am currently waiting on the chips to arrive.
I have big, grand plans for this little amp. Something along the lines of input --> MarshaValve --> Valvecaster --> Punch amp with a TMB stack in there somewhere.
Any thoughts or suggestions are welcome.

[seadi123]

I'm really irritated , i built the amp and the only thing i hear is buzz , just as i connect the battery . I have checked wiring many times and everything looks ok . Where is th4e buzz coming from ? http://picosong.com/YrDL/

[tca]

^ What schem are you using? Check: DEBUGGING - What to do when it doesn't work

Cheers.

[seadi123]

Oh , i got the chip pinout wrong :O

[tca]

Does it work?

[seadi123]

i accidentaly cut 2 of op-amps pins . they are so fragile . i have to wait another 2 weeks for other chip . i hate working with op-amps

[garcho]

Op amps are great, transistors are so overrated here it drives me nuts. Everyone needs obscure mojo parts to play standard rock guitar parts? Anyway, op amps always have pin 1 on the top left, along with a marking to let you know. Active filters, lfos, and all kinds of other cool circuits live in op amp land, don't give up on them!
@ Defiant: put the valve last!

[DefiantAudio]

Would it make much of a difference?