Hitachi FET Substitution

[still4given]

Originally posted by ashok


The difference in sound need not be due to the power transistors alone unless the rest of the circuitry , construction and parts type are absolutely identical.
Are the two amps identical in every other way ?
Cheers.

Hi ashok,

Sorry, I didn't mean to mislead.
No, the two amps are not identical. The S860 has a total of 12 MOSFETS and the PCR800 only 8. The S860 also has 1/4" inputs and the PCR800 RCA. The S860 is a little beefier I think and you may very well be right that other things have contributed to the sound more so than the MOSFET's. I was only sharing that the amp sounds very good and uses the Exicons. I would think if they were poor replacements that this would not be the case. If they weren't soldered in place on the Soundcraftsmen amps I would swap them out in the amps to see how much difference they really make, but that is more work than I am willing to do at this point. I should let folks with more electronic knowledge answer these questions. All I have are my ears and eyes. I have driven a pair of JBL 4425's, a pair of JBL 4411's, a pair of Yamaha NS1000's and a pair of Event 20/20's with these amps, and to my ears, the S860 is better sounding. One note though, the S860 is louder than the PCR800.

Here are my speakers


Blessings, Terry

[richie00boy]

I think you need even more speakers

[poor_lackey]

Guys,

Appreciate the insights

Koryusz, thanks for the offer but definately wanted the higher rated devices if I could find them.


Since starting this thread/looking for substitues, soundvalves has been offering matched hitachi 176/56's on ebay.
So I have taken the plunge.

The price was comparable with my expected landed cost for exicoms, and if the wife finds the bill I will hold fate accountable for my actions.


I don't expect that use of either product will contribute much in overall performance? (None that a simple lackey will notice).
As others have indicated there are many factors involved, layout PSU etc.
But having a low level understanding of fet output stages,
finding the spec'd devices as NOS is a good reason to jump in boots & all.


Now to start the fun stuff.


Finally
Can you ever have 2 many speakers? (assembled and working)

Thanks
Tony

[Koryusz]

no problem Tony.

Here are some pictures of my class A 100W amp using k405/J115

[Koryusz]

next picture, internal structure

[Koryusz]

K405/J115

[Koryusz]

power supply

[IFixAudio]

Hey Group,
My HAFLER is in need of a J160 and after reading threads on Exicon nad Magnatek subs and trying to find sources, I am not only confused but running out of options. I found a BUZ900 but no match.
Can anybody recommend any subs to get it running again? I will probably replace both, in both channels knowing it will probably cost me a whole pocket full of sheckles.

Thanks



Jim

[Henry8]

i messed about with one pair of genuine hitachi j50/k135.
there rated at 100w but behave more like 150w+
i then tried out 10n20/10p20, big dissapointment, plus some slight instablity issues
I ended up using rensasas j50/k135, works ok, but cant be pushed like the TO3 versions.

[Henry8]

Originally Posted by Henry8

I ended up using rensasas j50/k135, works ok, but cant be pushed like the TO3 versions.

oopps, i meant:-I ended up using rensasas j162/k1058, works ok, but cant be pushed like the TO3 versions j50/k135.