what would people advise for my first amp?

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RS have some 20watt 39volt zener diodes, would these be ok?

If you use a higher voltage supply then you will need to find some way to drop the extra voltage, or the amp will fry.

Zeners are not really the way to go - the problem here is that any form of voltage dropping ( without going to the trouble of building a switching regulator ) is going to have to dissipate the extra energy as heat. If you are using a 60v rail (for example) and you want to run your amp from a 42v rail , then the extra 18volts needs to be dropped by the regulator.
Suppose your amp draws 3Amps ( approximately the figure for a 60-80W amp ) from each rail at full load, the supply current will be the same for the regulator both before and after regulation , so the regulation device must dissipate:

P=I x V , or 3 x 18 = 54 Watts of heat for each rail.

effectively, for each extra 20v of secondary voltage you are dissipating about twice as much heat from the PSU as you would in the amp itself !!

you can do this, a simple way would be a zener and a pass transistor , but the transistor will get quite hot, and will need very good heatsinking. you can accept this if the voltage drop is quite small or the amp draws little power , but it's not ideal.
There are much better regulation ideas around - I suggest you search this forum - but you will probably end up spending more time and money building a regulator than you will on the amp, and they'll still have to dissipate the same amount!

It's a much , much better idea to match the transformer to the amp requirements if you want to build a simple project. Save the nice regulated PSU for another bigger project.
 
Re: opamp 5532?

dwjj said:
Wouldn't he really want the 5532-the dual opamp? That looks pin compatible.
What opamps are better than the opa2134?
My listening :bawling: tests say:
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NE5532 is better than OPA2134.
5532 gives better perspective and slightly larger roomspace.
Also a more comfortable feeling in the deep bass,
more distinct, especially with natural bass-guitars.
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So my choice is given: The low price NE5534/5532 all the way...

/halo - old and with a hearing below average,
take his listeningtest - with a GIANT LAUGH! :goodbad:
 
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