- Mar 19, 2013
- 1,612
- 2,694
- Disclosures
- If only I were that good....
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New PF-800 Cutting Out
- Thread starter Zach Gaston
- Start date
I don’t believe this is the cabs - I believe it is the same problem the PF500 and PF350 had/have, which was supposedly fixed ca 2014, but my PF500 which was built in 2015 faulted at each of the three gigs I used it at, and one rehearsal - each time as soon as I switched on a pedal that boosted the signal going into the preamp. I recall reading here that the issue wasn’t prevalent on the PF800, but there are a lot fewer PF800s in the wild than the other two - and I’ve experienced it once at home on my PF800, when using a Stingray.
These amps sound delicious but they can *not* handle a high input signal. I’m certain this is why Yamaha killed and replaced them - one look at the warranty service history and PCB board after warranty parts sales, and they said a loud “NOPE!”
These amps sound delicious but they can *not* handle a high input signal. I’m certain this is why Yamaha killed and replaced them - one look at the warranty service history and PCB board after warranty parts sales, and they said a loud “NOPE!”
My PF 500 has been sitting in my shed for years at this point after some sort of catastrophic failure that happened years ago and I have just never swapped out the board for a new one. I’d return it if you can and get a new one. I’ve owned scores of amps and this is the only one that ever completely died on my and I see issues with these here constantly.
@agedhorse is someone you should listen to. He designed the class D amps for Mesa (among others). The amp should not cut out like that. I had a class D amp from another manufacturer with similar problems. In all honesty I would recommend they sell or return the head and buy any of the Mesa Subway 800w heads for that gig. It sounds like they want enough volume to reliably keep up with a full pep band and carry an arena without being mixed into the PA. I can imagine what the director wants to hear and I would want a very reliable and powerful amp to handle that job. Mostly I would want to know I'm not pushing the amp anywhere near the point of failure to get those results. Not all 800w class D amps are created equal, not even close, and I'm generally a fan of Ampeg tones so I'm not trying to hate on Ampeg. There is a thread with nearly 47,000 posts on it about the quality and usefulness of the Mesa Subway gear.
You know, I find this very sad indeed. I was an early supporter and adopter. I bought an early PF 500 and then I went through three of them and they all failed to work in a relatively short period of time. What in the actual freaking heck is up with that. I chalked it up to being the new technology. I wanted to believe that, but I think it’s just a bad design now. I want my amp to last through my gigs or my backyard, barbecue, doesn’t matter. It should have some good reliability and they really haven’t been. and now it’s been about 10 years. This is still commonplace. Incredible’ There’s a thread on the 800 failures the 500 failures the 350 failures all ongoing so what the heck, in world, do they think we are completely and utterly stupid? Well, Maybe so…….me lol This is beyond ridiculous.
This in my mind, is completely unacceptable and unbecoming of a company with the name and reputation of Ampeg. And I know there’s various issues with various iterations and all that good stuff, but most people don’t give a company more than one or two tries. I gave them three with that PF series all fails. And they’re hardly the only one. I gave Carvin company three with their BA series of the class BA500 amps. 3 failed. Moved on. I know (hope) believe
that when designers, that are truly qualified to do the job, do it, they tend to do it well. If they take any pride in their work, they'll do it in a manner that creates a robust and professional product. One that not only works when the conditions are perfect, but works when conditions don’t quite agree with it. Whether thats being strong enough to withstand a few bumps and bruises which come with any piece of professional music gear, that isn’t studio gear. Or whether it’ll just run a little bit hot and keep going, or it’ll shut down. Of course great if it will save itself before it blows itself to bits. But sucks for the gig. . I’ve seen a lot of newer gear that does shut down from the heat on a hot day. Keyboards in particular Pads, mixers, etc. That’s unacceptable. And in my view I’m thinking that could be bad design. I guess maybe computers are just always going to be allergic to heat.
I’ve had 2 GK heads fall on the floor in the middle of a tune and keep on truckin’. I’ve had multiple Genz Benz heads, no failures. One even jettisoned the moving vehicle impacting on pavement popping the lightly padded plastic case open and merely dislodged the tube. Zero damage or failure. Reseat tube and play on. This is what pro gear should do and be.
This in my mind, is completely unacceptable and unbecoming of a company with the name and reputation of Ampeg. And I know there’s various issues with various iterations and all that good stuff, but most people don’t give a company more than one or two tries. I gave them three with that PF series all fails. And they’re hardly the only one. I gave Carvin company three with their BA series of the class BA500 amps. 3 failed. Moved on. I know (hope) believe
that when designers, that are truly qualified to do the job, do it, they tend to do it well. If they take any pride in their work, they'll do it in a manner that creates a robust and professional product. One that not only works when the conditions are perfect, but works when conditions don’t quite agree with it. Whether thats being strong enough to withstand a few bumps and bruises which come with any piece of professional music gear, that isn’t studio gear. Or whether it’ll just run a little bit hot and keep going, or it’ll shut down. Of course great if it will save itself before it blows itself to bits. But sucks for the gig. . I’ve seen a lot of newer gear that does shut down from the heat on a hot day. Keyboards in particular Pads, mixers, etc. That’s unacceptable. And in my view I’m thinking that could be bad design. I guess maybe computers are just always going to be allergic to heat.
I’ve had 2 GK heads fall on the floor in the middle of a tune and keep on truckin’. I’ve had multiple Genz Benz heads, no failures. One even jettisoned the moving vehicle impacting on pavement popping the lightly padded plastic case open and merely dislodged the tube. Zero damage or failure. Reseat tube and play on. This is what pro gear should do and be.
Oh yea, shout out to Agedhorse. Many here, have no clue the invaluable advise He gives here on a daily basis and how patient is with rookies beginners and neophytes. I swear he has the patience of a saint. He designed the GenzBenz amps, and currently designs Mesa bass amps. The list of credentials speaks for itself. Nuf said. Thanks man. We’re not worthy.
- Feb 12, 2006
- 60,977
- 5
- 220,730
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
IMO, the amp needs to be properly diagnosed and repaired. You have a good warranty on the amp, now would be a good time to use it.
Same - over 40 years playing, using many different amps, and the Portaflex class D amps are the only ones I’ve had this exact same problem with. OP should have them return it and buy a Mesa, Aguilar, Ampeg Venture, Genzler, etc.
I would try it without the pad and see what's up . If you don't have to crank the volume control as much maybe that might help but I doubt it .If that doesn't help take it to a tech .
I have worked on a few Ampeg PF-500 and PF-800 amps. Basically I just did a main board swap.
I know an electrical engineer who was on the team that designed those amps. He said those amps had good designs. The problem was they were built with the cheapest components in China. He also said that Loud Technologies would get broken warrantied amps back and just put a new board in. They would not bother to analize and find where the failure(s) were. Their QC sucked and it shows. The internet is littered with PF failure stories. It is too bad because they were decent sounding amps.....when they worked.
I know an electrical engineer who was on the team that designed those amps. He said those amps had good designs. The problem was they were built with the cheapest components in China. He also said that Loud Technologies would get broken warrantied amps back and just put a new board in. They would not bother to analize and find where the failure(s) were. Their QC sucked and it shows. The internet is littered with PF failure stories. It is too bad because they were decent sounding amps.....when they worked.
Have you tried a patch cable in the fx loop? Always the first thing to try with random cutting out.
That amp with those cabs should be capable of being unbearably loud, if you're pushing it so hard the amp's protection cutout is triggering you should probably be handing out hearing protection.
That amp with those cabs should be capable of being unbearably loud, if you're pushing it so hard the amp's protection cutout is triggering you should probably be handing out hearing protection.
THIS.
Diagnosing without having the unit on a bench is a best-guess. Why guess at all.
FWIW, the PF-350/500/800 series has had an over-reactive fault-mode problem in random units since it was first introduced.
Based on a steady 12-year stream of similar-issue owner reviews, I don't trust them as a product line, even while owning an issue-free PF-500 since 2012 - I just don't like the odds, even having possibly beat them.
Yamaha's recent discontinuation of the PF series heads is long overdue. They've subsequently dropped dealer cost to liquidate remaining inventory; Even if I rolled the dice at these prices and bought one that turned out to be problem-free, I'd have to ask myself how much faith I'd have in it for gigging without a backup.
BTW, I bought an Aguilar as a backup for gigging regularly, though I now use the PF-500 as the backup and the Aggie as the primary.
There are many better, more robust choices for gig-worthy class-D amps from companies like Mesa & Aguilar out there.
Yamaha has even introduced the new Ampeg Venture line that uses a more industry-standard/robust power amp section that might be worth watching reviews on in the months to come.
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Anecdotal evidence but my pf800, purchased new in 2017, has run flawlessly since day one. It's been thru many large hot outdoor stages to small indoor shows.
Hi Zach 
Would be a no brainer for me!
This is not normal!
You have a warranty case => send it in, have it checked!
greetings
Wise(b)ass
Would be a no brainer for me!
This is not normal!
You have a warranty case => send it in, have it checked!
greetings
Wise(b)ass
Is the speaker cable a Speaker Cable?
Being a school sometimes they just use what they have not knowing they are doing something wrong or have to order other parts.
We got lots of cables. Plug in and go.
You said recently purchased? I would suggest returning it and getting a Mesa or GK.
This is the answer, IMO. I had a PF800 and had it cut out once so I tried to replicate it. If I hit it with a hard transient, such as a strong slapped open E, I could get it to cut out. You may try keeping the gain down as much as possible and using the Master Volume to compensate but I just believe the amp's input doesn't have the headroom it should.
Attachments
How's the amp being powered? Could be the outlet is not supplying sufficient power. Can you try another outlet (not tied the outlet you're using)?? Also check your cables. Try a different set of cables. Possibly faulty cables.
Ampeg Discontinued the PF-800, PF-500, and PF-350
See: Ampeg – Bass guitar amplification
Often what happens with discontinued gear is replacement parts dry up.
These amps don't have a good track record, and chances are it's going to need service now or in the future.
If it's still under the store return policy, I would suggest you return it and pick up something with a good 5 Year Warranty!
See: Ampeg – Bass guitar amplification
Often what happens with discontinued gear is replacement parts dry up.
These amps don't have a good track record, and chances are it's going to need service now or in the future.
If it's still under the store return policy, I would suggest you return it and pick up something with a good 5 Year Warranty!
Thank you all for your advice! I can't respond to everyone, but I think the best course of action is going to be getting it looked at if not completely replaced. Someone mentioned power issues, and I considered that, but I don't think there's anywhere else we can plug it in, in the stadium. To some points people have been guessing about, I tried several different settings when I could get my hands on it, and I believe the student has been trying different things as well, it's definitely cutting out enough below the maximum that I don't believe we're pushing it harder than it should be able to handle. As for cables and other things, I made sure the set up was correct to the best of my abilities, and I'm pretty sure this is an issue with the head.
