phoenix gold xs4600

[poopydoopynoopy]

HI

This repair has me a little confused.
I got it to draw only 5 amps at startup, but it keeps melting ifr540's.
None of the drivers I check show a short.

Can someone give me a hint where to look?

paul

[1moreamp]

Yeah check each MPSA56 & 06 and 2sc2389 and each diode < some are zeners>. The outputs over bias to destruction due to bad driver circuitry and this includes bad resistors diodes and to-92 transistors...
I hate to say it cause these were great sounding and powerful little amps but when they go bad they take out the entire channels devices. I have found it faster just to gut the channel. It only costs some time and about $3.00 to do so...

[poopydoopynoopy]

Originally Posted by 1moreamp

Yeah check each MPSA56 & 06 and 2sc2389 and each diode < some are zeners>. The outputs over bias to destruction due to bad driver circuitry and this includes bad resistors diodes and to-92 transistors...
I hate to say it cause these were great sounding and powerful little amps but when they go bad they take out the entire channels devices. I have found it faster just to gut the channel. It only costs some time and about $3.00 to do so...

Hmm.....
Thanks!
I will report back...
p

[ComputerJLT]

i second checking or just replacing the mpsa56 and mpsa06 on that channel. I have a xs4600 that would randomly start popping on one channel and those were the culprit.

I replaced all of those transistors and readjusted the bias for all 4 channels per some info i got on phoenix phorum and that amp now sounds super clean and delicious lol

[1moreamp]

Originally Posted by ComputerJLT

i second checking or just replacing the mpsa56 and mpsa06 on that channel. I have a xs4600 that would randomly start popping on one channel and those were the culprit.

I replaced all of those transistors and readjusted the bias for all 4 channels per some info i got on phoenix phorum and that amp now sounds super clean and delicious lol

Yeah they do sound good once they are running in spec, better then most I have heard. I am guessing your advice source was Eric. He is the only one I am sure of that may any first hand info other there, other then myself, but I no longer visit that site even though I was founding member, and moderator for its two first years of existence. Glad to hear you got your amp running well.....C

[ComputerJLT]

valeks1 was who I talked to...


Would you prefer that amp over a Ti500.4? I just picked up a ti500.4 so I can use it to run my mids/highs with its internal crossover and bridge my xs4600 for my midbasses

[1moreamp]

Originally Posted by ComputerJLT

valeks1 was who I talked to...


Would you prefer that amp over a Ti500.4? I just picked up a ti500.4 so I can use it to run my mids/highs with its internal crossover and bridge my xs4600 for my midbasses

I actually use a Zenon 200.4 that never gets much past warm as I never get it anywhere near its clip point. Let me know if you need a whole main board for your 500.4 I have a factory spare sleeping in the corner here.

Valeks, I see him over on fleabay selling PG hardware and such, I guess he was one of the last few folks in Oregon before the big sell off to AAMP. I never met him, perhaps some day we can talk some. It has been a while since I was over at the PP...

[ComputerJLT]

but i mean sonically would you rather listen to mids/highs coming from a ti500.4 or from a xs4600. i have the option to buy another one right now for a good price even though I just bought that 500.4 lol

i do like the crossover on the ti though, i'll be using it to split the eq'd and ta'd signal from my RF 360.2 to my mids/highs in their pods at about 5khz. If i run an xs4600 i'll have to get a good crossover to do that as the internal one won't go that high

[1moreamp]

I don't want to start up a battle of SQ here on the forum as everybody hears differently as there are as many opinions about SQ as there are amps and amp makers.

Do as i do and setup a listening test where you actually sit and listen while sensing your on listening fatigue levels. If you can listen to it for hours on end then you got the correct SQ amp in place for your ears. It's as simple/complex as that.

Take the time to SQ test your gear, then you decide which is best where. I myself try not to mix amp designs. I pick one design and use it across the entire audio band. It makes it easier to tell is something is wrong sonically since they should all sound alike IMO...

The 500.4 is based on the MS series of amplifier design and is similar in layout and part designation to the battleships PG built in the early 90's. The XS amp is a RF / MTX counter measure design that uses a entirely different approach to biasing then either of those other bands uses. Mosfet amps and bipolar amps have been doing battle for years with no clear victor to the battle in sight.

So trying to decide here today would just be wrong IMO...