Gainclones and voltage PSU regulator

[gainphile]

Is there any specific/sonic reasons why gainclone designs generally uses very simple, unregulated PSU ?

What if I use voltage regulator such as LM338T? What kind of sonic quality/degradation would one expect ? This kind of regulator is not expensive.

Or is it because most of the design pursue "minimalist" philosophy ?

[angchuck]

its like you stepped on barren land after a war..... please do a search

[jackinnj]

Originally posted by angchuck
its like you stepped on barren land after a war..... please do a search

Well, the correspondent is a newly registered member so deserves a bit of help.

The PSRR of the LM3886 and 3875 are pretty darned good to begin with so regulating the supply burns watts which otherwise could be turned into music.

That being said, you should try regulating one and see how it sounds to your ears. It is not expensive in the least to build a really decent regulator with an LM317, current bearing transistor and a zener diode.
Take a look at National Semiconductor Application Note LB-47 for some guidelines.

[Nuuk]

I wasn't impressed with the LM338 regulated GC so I don't know if using an LM317/transistor will show how good a regulated GC is! On the other hand, the Pedja Rogic discrete regulated GC is the business.

Gainphile, if you are new to all this you may this of some help!

[Gopher]

Nuuk

That's not what your website says!

[Nuuk]

You have to remember that I wrote those comments 'at the time'. I hadn't heard the discrete regulated version then. But perhaps I should have said (above) that I wasn't that impressed with the LM338 regulated GC compared to the discrete version.

If I can find some time over the holidays, I will try and write an up-to date section on the Gainclones. For now, I will say that I find the best GCs are those using the SMPS or the discrete regulators.

And if you don't know already, there is another option for a regulated GC as described here . I haven't tried it myself so can't comment.

[gainphile]

Thanks all. I've had few readups before posting this but seems like there is not a clear concensus. Anyway that info about the LMs already having a ps regulator is new to me ! I guess I won't be fixing stuff that's already sound great then...

[Nuuk]

Anyway that info about the LMs already having a ps regulator is new to me ! I guess I won't be fixing stuff that's already sound great then...

PSRR stands for Power supply ripple rejection ratio and not power supply regulation. You can read a bit more here .

The beauty of the Gainclone is that you can build one comparatively easily and then try out all the well-documented variations without spending too much time or money.

[ionomolo]

Regulation is not recommended since a regulator is, in fact, a voltage amplifier and it needs to change it's output at least as fast as the LM3875/86 does. Most regulators don't do and create a phase shift between output voltage and current (parasitic inductance) that is worse than simple 100Hz ripple since it's releated to the output signal.

Unregulated snubbered psu gives the best results.

[Leolabs]

Unless the quality of your main AC is bad,otherwise dont need any regulators for the gainclone.