Any quality LM4780 PCB designs around?

[Lingwendil]

I gave most of my extra IC stash away to the raffle at Burning Amp this year, but just found four more (!) LM4780 while digging through some parts this week. I figure I may as well build something with them to mix it up a little from my usual focus on tubes. Are there any decent PCB designs still around for these chips? I'm looking for a simple parallel build, one chip per board. A DC servo or error opamp would also be a cool feature, but not a big deal or dealbreaker in either case.

Most of the cheap Chinese PCB offerings aren't the greatest, and don't impress me.


I suppose I could draw something up but for only two boards that feature a discontinued IC I'm not sure it's worth the rather limited time I have.

Any recommendations or leads that you folks have would be appreciated.

 

[tomchr]

My Parallel-86 would be a good choice. Sadly, I've discontinued that circuit as the LM4780s are no longer available from TI. You might have some luck finding unused boards in the Swap Meet, though. I do see them pop up on occasion.

Tom

 

[yoaudio]

PA03 Pavel Dudek's

Pavel Dudek's PA03 was popular a few years ago.

Sjostrom Audio - PA03 Pavel Dudek's deLuxe Gainclone

I may have an extra board in my stash, let me know if interested, I'll look for it.

 

[mexmike]

Have a look at this...
LM 4780

Looks very simple!

 

[jackinnj]

I have parallel, bridged and dual boards -- $3 each as the LM4780 is discontinued.

 

[leadbelly]

Ooh, interested. What's a "dual" board?

 

[jackinnj]

Ooh, interested. What's a "dual" board?

stereo

 

[jackinnj]

PM me if interested, there is nothing original in the design as all the designs follow the NSM/TXN notes -- there was an article in AudioXpress as well. I've sold hundreds of the boards and still have tubes of LM4780 available but don't want to carry inventory.

 

[SCD]

Hello Jack:
Could you provide a little more info about your boards. I have a few of these chips and was thinking about building something as well.

 

[asuslover]

If you want a composite amp take a look here:
Sympatico Amplifier

 

[Lingwendil]

I have parallel, bridged and dual boards -- $3 each as the LM4780 is discontinued.

Any way you can post up the board layout, and maybe some details? I may be interested.

 

[jackinnj]

LM4780 stereo board:

 

[aparatusonitus]

If I'm not asking to much, could you also uploud pcb artwork for parallel as well as bridge varians, thanksl! Would also like to know are you willing to send abroad (Croatia, EU)?

 

[jackinnj]

Parallel board

 

[avtech]

Interesting timing as I've just ordered some of these chips...

 

[jackinnj]

Bridged:

 

[aparatusonitus]

Thank you...I really appreciate it. And again..are you willing to send abroad (Croatia, EU) shipping cost estimate?

 

[jackinnj]

Thank you...I really appreciate it. And again..are you willing to send abroad (Croatia, EU) shipping cost estimate?

Regrettably, US businesses are subsidizing Amazon so shipping to EU is going to be $13, Canada and Mexico are a bit less. US Shipping $6.65.

I have several tubes of LM4780 chips. These are $6 each.

 

[Lingwendil]

Hmmm. How are the parallel boards implemented? Is it basic datasheet stuff, or is there some "secret sauce" going on?

I might be interested in a pair or quad.

 

[SCD]

hello Jack:
I am interested in a pair of bridged boards. That will give me a nice set of mono blocks for some support woofers for my horn set up.