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Ampeg Portaflex 500 problems

77mmstingray

77mmstingray

Guest
Jan 29, 2012
88
1
#1
My Ampeg Portaflex 500 crapped out at a gig last night for the second time.
The first one was replaced under warranty. Now it is 4 years old
While I like the warm tone of this amp ( I use an Ampeg 4-10 bottom)
I don't like the reliability.
Can anyone suggest an amp with similar tone and features?
Thanks
 
#6
77mmstingray said:
My Ampeg Portaflex 500 crapped out at a gig last night for the second time.
The first one was replaced under warranty. Now it is 4 years old
While I like the warm tone of this amp ( I use an Ampeg 4-10 bottom)
I don't like the reliability.
Can anyone suggest an amp with similar tone and features?
Thanks
Click to expand...


The 500s were/are known for overheating problems, among other things. Get rid of your 500, and get an 800.
 
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#7
MadCow217 said:
The 500s were/are known for overheating problems, among other things. Get rid of your 500, and get an 800.
Click to expand...
I acquired a dead Portaflex 500 about 7 months ago free from the music store I was working at at the time. It was a used item, and when it stopped working they simply let me keep it.

Do you (or anyone else... @JimmyM @beans-on-toast @agedhorse ???) happen to know what the common fault was with the seemingly common PF500 meltdowns? I’m hoping it will be repairable on the cheaps.
 
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#8
SuperK said:
Have you looked at the Aguilar Tone Hammer?
Click to expand...
A sound tech friend said the Tone Hammer can and does have crap out issues too.
There is always bound to be a clunker in every batch of any amp.

I'm knocking on wood as I write this, My PF-500 that I bought used has worked flawlessly for 4 years and it was used heavily for slap bass by the previous owner.
I never asked how long he had it or if he was the original owner but it must be 7 to 8 years old by now.
It also has a picture of a musician on top of the amp that covers the Ampeg "A" logo. He said it was his old music tutor, the keyboardist that was with Mars Volta who has long since passed away. So there's that mojo and protection that keeps it running nearly every day for woodshedding and gigs. I'll never scrape the picture off.
 
#9
Texican said:
I acquired a dead Portaflex 500 about 7 months ago free from the music store I was working at at the time. It was a used item, and when it stopped working they simply let me keep it.

Do you (or anyone else... @JimmyM @beans-on-toast @agedhorse ???) happen to know what the common fault was with the seemingly common PF500 meltdowns? I’m hoping it will be repairable on the cheaps.
Click to expand...
Not likely to be repairable "on the cheap". Sorry.
 
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#10
Texican said:
I acquired a dead Portaflex 500 about 7 months ago free from the music store I was working at at the time. It was a used item, and when it stopped working they simply let me keep it.

Do you (or anyone else... @JimmyM @beans-on-toast @agedhorse ???) happen to know what the common fault was with the seemingly common PF500 meltdowns? I’m hoping it will be repairable on the cheaps.
Click to expand...
I do not. All I know is you can get motherboards for them from Full Compass at a fairly reasonable price. Or at least you could...not sure now.
 
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#11
Texican said:
I acquired a dead Portaflex 500 about 7 months ago free from the music store I was working at at the time. It was a used item, and when it stopped working they simply let me keep it.

Do you (or anyone else... @JimmyM @beans-on-toast @agedhorse ???) happen to know what the common fault was with the seemingly common PF500 meltdowns? I’m hoping it will be repairable on the cheaps.
Click to expand...

There is no simple answer. Start with an close inspection, looking for signs of blown components. Reseat the internal connectors you might get lucky there. Sometimes the solution is as simple as that, but most often not.
 
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#14
Texican said:
I just tried a portaflex 500 and a V4B side-by-side at guitar center. The V4B blew away the portaflex 500 in my opinion. I tried each head through the matching cabinet. The Portaflex got the 210 flip top cab, and the V4B got the 212AV.

Nothing wrong with the PF500, but I think I want a tube amp.
Click to expand...
V4B does rule. Was my first tube amp. Lots of good times with one of them.
 
#15
Texican said:
I acquired a dead Portaflex 500 about 7 months ago free from the music store I was working at at the time. It was a used item, and when it stopped working they simply let me keep it.

Do you (or anyone else... @JimmyM @beans-on-toast @agedhorse ???) happen to know what the common fault was with the seemingly common PF500 meltdowns? I’m hoping it will be repairable on the cheaps.
Click to expand...

The driver chip for the Class D amp tends to fail.
also the driver chip and typical diodes in the switch mode power supply die.
both from same chip ic producer. most of it is design error for the amp.
but the IC producer has upgraded the chips.
likewise Ampeg revised the amp with the newer chips

otherwise updated amps with new chips depending on how much power the user actually uses
people actually using 400 watts or more will hit thermal shutdown regardless.

likewise as the op has discovered expect 3 to 7 years or 2000 to 3000 hours from
most general purpose switch mode supply's. this one died at 4 years
no surprise. other user timelines will vary depending on hours of use and total average current

as far as repair
would be the usual driver replacement for the amp.
power supply would be the usual toasted diodes and replacing high esr caps
when the diodes or mosfet take a dump as long as traces are not burned up from arc over
its replacment of the diodes and whatever else it took out. usually surface mount parts.

usually there is no spark gap or arc over slots cut on these cheaper power supplies
so aside from simple surface mount component replacement. if the traces get torched then the board is no good
 
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#16
I think you will find that SMPS lifespan depends more on the quality of the design than on such short hours and time span.

As an example, I have a ~300 watt class D module running in my shop that's been running for over 10 years non-stop. That's clearly beyond 3-7 years, and at at 85,000 hours it's obviously well beyond the 2000-3000 hours stated above.
 
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#17
but in this case its 4 years
for whats posted. and in many many other other threads the same usual 3 to 7 years

im not here to argue about switch turd power supplies.
just answering the question to the known issues of the PF500

assured the 2000 hr caps in the thing will do exactly 2000 to 3000 hrs

unless your power supply has been doing 300 watts at full power for 10 years.
like i said last time. forget the power supply lol. what amazing dummy load are you running at 300 watts for 10 years.

having designed 800 watt switch modes for servers. i assure you they exceed typical bass amp supplys
for quality. yet again the system is designed with 3 back up power supplies and can be hot swapped
even if backups fail.

most systems get to 3rd backup in 5 years. but usually the primary is hot swapped immediately
after the first failure.

oh dont worry they are loaded with 10,000 to 12,000 hr caps.
but they still fail within 3000. its the downfall of the topology. the end
 
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#18
I'm just stating that my experience is consistently very different than yours. I'm sure others have had better experience than you have as well.
 
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#20
dtripoli said:
A sound tech friend said the Tone Hammer can and does have crap out issues too.
There is always bound to be a clunker in every batch of any amp.

I'm knocking on wood as I write this, My PF-500 that I bought used has worked flawlessly for 4 years and it was used heavily for slap bass by the previous owner.
I never asked how long he had it or if he was the original owner but it must be 7 to 8 years old by now.
It also has a picture of a musician on top of the amp that covers the Ampeg "A" logo. He said it was his old music tutor, the keyboardist that was with Mars Volta who has long since passed away. So there's that mojo and protection that keeps it running nearly every day for woodshedding and gigs. I'll never scrape the picture off.
Click to expand...

I have had and used consisently a TH500. Bought it new in late 2916. Never a hiccup. Perhaps its non-intuitive control layout and functions threw the tech a curve ball?
 
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