PUNCH - 1W amplifier

[S_DANILO]

Hello everybody! Newbie needing help!

I've chosen the Punch Amp to be my first DIY project, and I actually think I was successful since I had never used a soldering iron before, but the thing is the amp is not working (as expected from a newbie!)...

What is the chip that you are using TDA7052 or TDA7052A?

I'm actually using the TDA7052B

[tca]

I'm actually using the TDA7052B

Funny 

That is the problem: the TDA7052B also has DC volume control! Can't see the differences between version A and B?!? Have to check the datasheet.

Cheers.


P.S. (edit)

More gain for the A, less noise... I'm guessing but it seems that the A version is a "deluxe" B version .

[chromesphere]

Didnt even know there was a B!!

Are you sure you havent messed up your layout Danilo?   You said your new to this.  That would be the biggest margin for error and most likely cause if you ask me.

Paul

[S_DANILO]

Just downloaded the B version datasheet and saw the DC volume... Thanks for the input Tiago!

As Paul suspected, I have also committed a few other "crimes" when I was assembling it, so I'll just buy a vero board and start all over again.

Anyway, I have to mention that I really enjoyed to do this project, even that it didn't work...

Thanks a lot for all the help you guys provided!

Cheers
Sergio

[garcho]

so I'll just buy a vero board and start all over again.

Etching is easier than vero. Perf is easier than vero. Proto-board is easier than vero. Point-to-point is easier than vero. Anything is easier than vero!    Seriously, some people here are wizards with the stuff, but it's really easy to get a solder bridge over a strand of copper flailing astray from drilling the 'cuts', among other reasons. It's never too soon to start trying to make your own PCBs. Or leave those leads on and start perfing.

[S_DANILO]

so I'll just buy a vero board and start all over again.

Etching is easier than vero. Perf is easier than vero. Proto-board is easier than vero. Point-to-point is easier than vero. Anything is easier than vero!    Seriously, some people here are wizards with the stuff, but it's really easy to get a solder bridge over a strand of copper flailing astray from drilling the 'cuts', among other reasons. It's never too soon to start trying to make your own PCBs. Or leave those leads on and start perfing.

@garcho, thanks a lot for the input!

Cheers.
Sergio

[deadastronaut]

I have to mention that I really enjoyed to do this project, even that it didn't work...



Cheers
Sergio

thats the spirit..

you'll get there in the end..

[therealfindo]

Hi.. I'm looking to make this project (on vero) with a couple of bookshelf speakers I've got lying around. But a couple of questions still (having read through the entire thread)

a) How would I incorporate the volume and tone control to this circuit? (Edit: I found this variant - http://i.imgur.com/URTeFuF.png?1 which has a volume pot - could I simply add a tone pot like the one in a guitar setup, with a cap going to ground? If so, which values?)

b) Did anyone figure out how to add a headphone output as well?



Thanks!

[chromesphere]

Hey, the volume control is a feature of the tda7052a <-- note the a suffix, and is connected to pin 4 of the chip.  The tda7052 doesnt have a volume control so make sure you get the right one.

Only thing i could think of for tone control is an input cap blend tone control.

for the headphones, no special requirement.  Just plug them in.  Pretty sure the MCL feature of the chip automatically adjusts its current when headphones are plugged in.  I should say, i have tested it and its fine with my set up.

Hope that helps.

Paul

[MaxPower]

Is the TDA7052 pretty common? Mouser only has the surface mount version. Should probably check mammoth and i see if they carry them....

[chromesphere]

You can get them on ebay if you get stuck.  Just make sure you get the TDA7052A if you want the volume control option.

[deadastronaut]

quick ?

will this kill a 9v battery..or  6 x 1.5 AA's  rapidly?...anyone tried it yet?.

i just fancy a seperate little amp to go with my roland micro cube...so i can jam to backing tracks when camping, holiday etc..

my roland lasts up to 20 hours on 6 AA's..

so just wondered how this would fair

[chromesphere]

Someone was saying the punch amp ran down quickly because it should be ran at 6v instead of 9v.  Might be worth giving it a test run?  Havent ran mine on batteries so no idea.

[chptunes]

Concerning the use of a 9v Battery.. I documented a little experiment, back on page 4 of this thread.  This little Perfboard Punch remains in the corner of my Family Room.. I use it for unscripted jams every week.. original battery still installed.

Here is the quoted reply:

BTW I wasn't saying the TDA7052A is any more or any less efficient than others (though in IMHO, most small audio ICs you see in stompbox type circuits are much of a muchness - if you seek efficiency, then a class D' audio IC is the way to go ....but try finding one of those puppies that you can solder easily in a through hole package!)...I was just pointing out that for battery purposes,  at high volumes into an 8 ohm speaker, the TDA7052A will drain a 9V battery in very short order (cos like all BTL amplifiers it gives double the voltage swing across the speaker vs. a single ended amp like the LM386)

So.. I did a real-world test.

I have built several Punch Amps.. they are fun to build and easy to apply in different situations.  The Punch that I used for this test is on Perfboard, with an on-board 100k Volume Control (Trimmer).

Here are images of the test amp:



I opened a fresh Alkaline.. measured 9.48vDC.  Connected the battery to my test amp, with Volume Trimmer set at 100k ['just above conversation-level' output with dry guitar (single-coils)].  Current draw at idle measured 10.7mA.

Played random notes/phrases/chords for approximately 5 minutes...

Inserted my AMZ Tweed Stack Preamp and enjoyed sweet overdriven tones for approximately 10 minutes...

Unplugged my guitar, but kept the guitar lead plugged in with the test amp still 'On'.  Current draw measured 10.7mA.. went to bed...

Woke up after 7-7.5 hours, and measured voltage at 8.28vDC.  Plugged my guitar in and enjoyed 'just above conversation-level' output for approximately 10 minutes...

Unplugged from test amp.

Conclusions:  Into a 12 Ohm load, with 100k Ohms on Pin 4, battery power is very feasible for the purpose of casual 'living room' use and pedal auditioning.  Don't leave it 'On' while you sleep.  

Food-For-Thought:  My Punch still sounds fine at 8vDC.. the TDA7052A chip will operate down to 6vDC.

-Corey

[deadastronaut]

cool....sounds good to me then, , cheers,

[therealfindo]

Hey, the volume control is a feature of the tda7052a <-- note the a suffix, and is connected to pin 4 of the chip.  The tda7052 doesnt have a volume control so make sure you get the right one.

Only thing i could think of for tone control is an input cap blend tone control.

for the headphones, no special requirement.  Just plug them in.  Pretty sure the MCL feature of the chip automatically adjusts its current when headphones are plugged in.  I should say, i have tested it and its fine with my set up.

Hope that helps.

Paul

Thanks for that Paul!

*googles "input cap blend tone control"* 

Cheers.

[chromesphere]

Thanks for that Paul!

*googles "input cap blend tone control"* 

Cheers.

YOu can see an example here (the 'blend' control):
http://www.generalguitargadgets.com/pdf/ggg_ff5_sc_easy.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a
easy to implement just make sure you put the lower and higher values around the right way otherwise the control will have no effect.
Paul

[smurfedelic smurfberry]

here's my enclousure... abs plastic, aluminium tape covered inside..

I like it, it's a bit "thin" when it comes to the sound, but it's awesome. I guess the 5w Sparky is the next amp i build haha

[kingswayguitar]

here's my enclousure... abs plastic, aluminium tape covered inside..

I like it, it's a bit "thin" when it comes to the sound, but it's awesome. I guess the 5w Sparky is the next amp i build haha

cool papa smurf
couldn't get your weblink to work though

[smurfedelic smurfberry]

Ah, damn, it's mydiypedals.tumblr.com not .org