Dave Barber is a sick man...

[Marcos - Munky]

What about a DS-1 with Seeying Eye mod and parallel opamps? Sounds cool.

[ahermida]

On that same note, I've seen diodes in parallel the clipping stages.

Alf

[javacody]

Here is what I've found in a wee bit of experimentation tonight:

Combos tried in a Tubescreamer (modded TS5 to TS808 specs):

TI RC4558P (by itself) sounds a little sweeter than a JRC4558D
TI RC4558P + TI RC4558P = a little fatter
TI RC4558P + JRC4558D = a little fatter still
TI RC4558P + TA75558P = best of all, fat and a little more highs

I've found my combination for now. It is a definite improvement with that last combo, but with the first two combo's the differences were slight.

[Paul Marossy]

Not to toot my own horn, but I tried doing that about a year ago, with a pair of JRC4558D chips. I couldn't really tell much of a difference in the circuit that I tried it in. I kind of forgot about it until now...
What kind of circuits would piggy backed opamps really shine in?

[javacody]

Paul, from what I can tell with the 3 combo's I tried, two of the same chip together just slighly fattens the sound. You have to listen for it. It doesn't jump out at you. It seems like the further away you get in specs, the more difference in sound you get.

[Ansil]

OK, could i put two 386's together?  you know, for a "little gem" amp?
im making my wife a little guitar amp, but wanted something more
powerful than 1/2 watt.  what kind of changes do you need to do
to the circuit to make it work?

thanks!  :wink:

damn..  i was wondering how long it woudl take someone to ask that.

[javacody]

I asked that in the other forum first. Nya Nya  

[Ansil]

what the 386 piggy back.  yeah i was wondering how long it would take someone to do that.  i talked to a few chaps in email about it some time ago. and even had a clip. but htey were wired different than just piggy backed. exactly parrallel. but everyone looked at me like i was crazy.. lol.. oh wait i am.
:twisted:

[Boofhead]

It's actually the production line for NOS RC4558D's - the stork isn't real.

[Jered]

As Aron said previously, we've done this with fets, mosfets, it adds clarity if you pay very close attention to your specs. Check out almost any Matchless pre amp, lots of neat ideas.
   Jered

[Marcos - Munky]

Hey, the Sans Amp stuff woud sounds crazy with this.

[javacody]

Can I simply add another JFET in parallel for more clarity in my buffers?  Hmm.

[smoguzbenjamin]

Hey Ansil, how did the 386 piggy-back work out? Do you get more amplification? Or just a different sound? I was thinking of making a little gem (if I can ever get the IC I need) but 1/2W is a bit too little.

Or could I take the output from the first LM386 and run it through another 386 IC?  :roll:  I was wondering if maybe that'd be too loud and the 2nd 386 would start clipping.  :?

[javacody]

smoguzbenjamin, I tried my Radio Shack LM386 last night at 12 volts, and it increased the output significantly. Also gave me much more clean headroom. I'm going to try piggybacking the lm386's tonight.

[smoguzbenjamin]

12 volts, eh? Hmmm. Could be a pain in the ass battery-wise though. Any charge-pumps for converting 9V to 12V?

Javacody: post your results please!

[RDV]

12 volts, eh? Hmmm. Could be a pain in the ass battery-wise though. Any charge-pumps for converting 9V to 12V?

Javacody: post your results please!

Most unregulated 9volt wall-wart type supplies run between 12-14volts. That's what I run mine with. Works really well with the little 1 watt mini-Marshall amps too.

Regards

RDV

[Ansil]

i piggy backed mine so that the bottom chip was connected up normally
and the second one was connected to v+ and gnd.  and pins 1 an eight were tied together..

nice and crunchy

[smoguzbenjamin]

Yah I used to haev a wallwart that supplied 12V but it broke because I sortof stood on it once and that was that...

I want to make a little gem type mini-amp for playing at school, so i'm really going to want to use batteries...

[javacody]

A nine-volt with anything bigger than a 3" speaker isn't going to last very long. Some people around here recommend using several C's (you get longer battery life and can get 12 volts using 8 C's)

[smoguzbenjamin]

I was actually planning on mounting a 1/8" jack for headphone use But with the possibility of maybe a small (2 - 2.5") speaker I thought it might be good to have some extra gain in there. I'm also trying to keep things small, so 8 C batteries wouldn't be what I wanted... What about piggy-backing 386's, would that work?