Peter Purpose 2520 max voltage

I have a couple of these running in 312 clones, very nice sounding!  I've searched but I can't seem to find anywhere where a max voltage is clearly stated for peter purposes 2520s.  I'm guessing its 18v...  I have them running at +/- 17v now.



Thanks!

As they are a near identical clone of the original, you can go up to 22v.

Thanks Walrus, I appreciate you chiming in! 

According to the original datasheets:

http://www.groupdiy.com/index.php?topic=44738.msg561131#msg561131

2520's can handle up to +/-20VDC. 

I think they could handle more but might not be able to dissipate heat fast enough... At least I remember some talk about that somewhere.

thanks for the responses guys... mitsos, I actually found that datasheet, though through another link.  I've been running them at +/-20v for a bit, even before I found the datasheet, just to be safe as these are great sounding little beauties.

do they get hot at +/-20V?  I think I've had some at +/-18V before.

I have run them for a few hours at a time like that.... and it wasnt hot enough to cook my eggs... maybe warm, though I didn't actually touch the op amp while it was on....  seemed fine, but perhaps I'll back em off to 19v just for safety...  :-\

more voltage = more gain out of them?

I don't understand this sport. Could you enlighten me what the advantage of increasing the DOAs supply voltage might be in a API312 circuit, other then increasing the risk of frying a following unit or the need to pad levels down even further ?
With +/-16VDC supply, these -from API3124 technical data- can deliver +28dBu.
Just a rough check, LOG((((32/2)-2*0.7V)/SQRT(2))/0.7746V)*20+6.02dB from output transformer=28.51dBu seem to confirm this. Your +/-17VDC supply will already give a 29.1dBu max.out. A +/-20VDC supply might further increase this to 30.6dBu.
Seeing FI the +28dBu max.allowed input range of a prism ad-2, not being the flimsyest part around, I don't get the point of the desire to increase the DOAs supply voltage in this context.

There is a TV commercial on US TV where a group of very young kids explain why more is better. This may involve a similar mindset.,
=====
When increasing DOA operating voltages check that operating current density, class A bias, etc are not increasing to the point where dissipation becomes problematic.

JR 

I'm running mine 17.5 V just like the original.

Yes, admittedly, I think John got it right... I had in my head to run these close to max +/- simply because I could, without really considering real world benefits.  Just thinking more headroom, higher dbu output, but I hadn't considered whether or not I need it.  Thanks Harpo, for doing the math for me, you are certainly correct once I think it through, there is no real world benefit for me to run these hot.  Even though I've looked at the datasheet, I failed to think about when anyone (specifically me) would actually need >28dbu. 

Thanks for reminding me to think about why I'm doing something, not just whether I can or not!

;D

atticmike, do you have an original schematic that shows +/- voltages?  most things I've seen omit the power rails....

Seeker said:

atticmike, do you have an original schematic that shows +/- voltages?  most things I've seen omit the power rails....

Click to expand...

Sure, had been doing soul-searching for that project but you'll have to wait couple of hours before I'm able to look it up.

Seeker said:

Yes, admittedly, I think John got it right... I had in my head to run these close to max +/- simply because I could, without really considering real world benefits.  Just thinking more headroom, higher dbu output, but I hadn't considered whether or not I need it. 

Click to expand...

Consider that the vast majority of gear out there runs on the usual +/- 15 V split rail supplies, having output swing that exceeds that doesn't buy you anything. And then you'll have to watch to ensure that you don't clip those +/- 15 V stages with your higher-level output.

-a