Finished my GainClone

[dezzz]

I just finished my GainClone, and I have a few questions to ask. I am using the Premium kit, and a 300VA toroid 2*20Volts. The sound sofar is magnificent, with a very good placement of the various instruments used. However...

I have more than enough power at my disposal, and so I was thinking that maybe I could lower the amplification, and achieve lower distortion figures, is this possible...?

My own speaker are driven perfectly(largest driver is a 7" Eton), I then took the amplifier to a friends house, and his much bigger speakers, 2*8" Vifa basses. The amplification is still adequate, but the kick in the bass is gone. Could this be improved on by implementing a larger Capacitor, maybe 3300 or 4700 instead of the Panasonic 1500. And what would the cons of this setup be...? Much slower bass?

Hope you can help me...

[troystg]

Hi dezzz-

Most likely his dual 8's are creating a 4 Ohm load. If you parallel the LMxxxx chips you would see that the snap and slam would mostlikely return.

Is your Eton 7" a 4 or 8 Ohm driver?

[alexw88]

Yes, adding more capacitors would help the bass a bit, but the mids and high won't be good anymore.

I am also running 4 ohm speakers, from my experience the following would help improve the bass (when driving 4 ohm speaker):

1. Run a higher voltage, 25V secondary seems good.
2. Regulate it, if you don't use regulator, when driven hard, supply voltage will sag for 1-2 volt. which would reduce the power.
3. Use LM3886, it can provide more current for 4 ohm load.
4. Parallel 2 3886s for even more power and current


I have done all of the above and I can say the bass of my amp is now very good.

[dezzz]

Thank you for your replies...

His two 8"s are originally 16 Ohm, but they are connected in parallel, so that is 8. And so is my Eton, thats why I thought they simply needed more power...

I might just try to add a regulator...

What about a valvebuffer, would that improve on the attack?

One more question, is it possible to wrap the toroid in a thick layer of aluminum foil, or something alike, to screen it of from the rest of the circuits, I am preparing a very small chassis for it, that is why this is of interrest...

[alexw88]

You are running at 20V, after the rectifier it will be around 28V, if you regulate it, you may need a drop out of about 5V.

So after regulation it will be around 23V, which will give you less power. If you want to regulate, you need to start with a higher voltage.