# For the Amp Guts experts [old school]



## Jethro (Jun 14, 2007)

OK, so I've got three older amps that I've used quite a bit, and have recently wondered how the amp guts experts would rate them...

First one... rated at 75Wx2 @ 4 ohms... birthsheet says 384W bridged @ 4-ohms (actually it says 192W @ 2-ohms, all channels driven)...










Second one... rated at 50Wx2 @ 4-ohms, but seemed to perform above and beyond that (compared to similarly powered amps I've used)...










Third one... supposed to be double the power of the others, although birthsheet says 426W bridged @ 4-ohms...










Any thoughts or comments?


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## dejo (Jan 3, 2006)

let me guess, rf punch 75, xtant and obviously the pg ti. id take the pg over the other either way


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## Jethro (Jun 14, 2007)

dejo said:


> let me guess, rf punch 75, xtant and obviously the pg ti. id take the pg over the other either way


Close... Punch 150HD... Xtant 202m... PG Ti400.2

Incidently, I ran both the PG and RF amps to the exact same sub, and the difference in output was A LOT more than the birthsheets would indicate... so I'm guessing the RF's sheet is misleading me.

If I figure [426/384]log*10, I get a difference of a mere .45 dB... and I know the difference was more than that... it was pretty severe clipping at full volume with the P150 vs. none whatsoever with the Ti.

I guess I could be misinterpreting the RF birthsheet... maybe 192W is all it does when bridged... [426/192]log*10 = 3.46 dB difference, which seems to be about right. Of course, ears aren't exactly precision instruments, so I could be mistaken.


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## Ge0 (Jul 23, 2007)

dejo said:


> let me guess, rf punch 75, xtant and obviously the pg ti. id take the pg over the other either way


That was my guess but could not determine models. Just design philosophy.

To the OP.

I have mixed feelings about RF designs but love Xtant and PG's work. Any of the 3 are decent choices.

Ge0


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