Second PF-500 Burnt-Out Last Night.......

[JimmyM]

I agree, and I would add that this amp is not for everyone. As I stated earlier, I consider it the Squier of amps, and I don't mean that as a put down to either Squier or the PF series of amps. IMO it is a good entry level amp that will work for the average weekend warrior. IT IS NOT, IMO, A PRO LEVEL AMP.

I get that comment, but that said, I've used my PF350 in a lot of pro level situations, and while it's not quite my Heritage SVT it's held up great for close to two years now and taken a good pounding on occasion trying to get it to cut out and I can't make it cut out. And seeing as how people with problems have assorted problems and not just one thing, it sounds more to me like manufacturing defects rather than design flaws. When it happens to you, it's no fun at all, but on the bright side, Ampeg's trying hard to make folks happy who have had problems. Can't comment with any inside knowledge of failure rates, but I know they cost Ampeg money. If they were getting an inordinate amount of returns, they'd pull the product line and stop the bleeding.

 

[jumblemind]

Sorry, I didn't miss any of that. I discounted the store failure, since almost everyone seems to agree that floor models are notoriously abused. After twenty-five years of playing two to three times per week and more, I am well aware of the differences in playing at home and playing with a band. I respectfully disagree with your opinion that overplaying the amps capabilities is not user error. Any seasoned player will tell you that constantly playing an amp at max volume is just asking for trouble.

Wait, I thought you said in bold letters that volume isn't an indicator of what power an amp is putting out. To the point, most people aren't at max volume when they have these problems. The store defense doesn't hold water on its own. No one is in the store cranking the head to max volume for hours to the point where it would seem likely the time I go to demo it burns up when the power switch is turned on. All of these little reasons, excuses are whatever would make perfect sense on their own and not all together for the same amp line.

Yet, I constantly see posts on Talk Bass that lead me to the conclusion that younger players simply do not understand this concept. Most of them seem to think that you should always run your amp at eleven. That's my just my opinion/experience, YMMV. Note: If you go back and read the post you are referring to, you will see where I stated that the posters experience may not be the same as mine, depending on his particular setup. I stand by all the statements I made.

John out.

It's cool. I've also been playing and gigging for 25 years, running a ss Ampeg for close to 10 of those. I also have a Micro VR that I gig occasionally without problems. I know how an amp should behave, especially an Ampeg. My "setup" with my particular cutout experience was a stock 75 P bass run straight into the PF350. Saying that any amp shouldn't be turned up past noon is just odd to me, especially when there's an official Ampeg YouTube vid where the dude shows you how to properly dial in the gain stage (and it's well past noon).

 

[JimmyM]

Yes, you definitely should be able to crank it. Personally, I don't think most micros sound good when you crank them super loud (except the gain...that does sound good), but it definitely should be doable to crank the gain as hard as you want in the Ampeg micros.

 

[TinIndian]

Yeah, I have heard nothing but praise about GB quality. Their sound just doesn't do it for me.

And thats fair. I was really commenting more on reliability of class D amps though. From what I've heard, that PF350/500 is a good amp and delivers on the Ampeg sound. If I didn't dig my GB I'd probably looking at a PF500. All makes have failures, what makes the difference is how a company handles those situations and it seems Ampeg is trying to make good.

 

[Jim C]

How about this:

Ampeg made and continues to make huge numbers of these amps; it's significant but it couldn't be more the 20% of the lightweight 500 watt bass amp market.
They sure get a bad rap here.

We don't know if the failure has been corrected in manufacturing as there is no way of knowing how new or old the majority of failures are.

My questions:
Do the repaired amps continue to work properly?
Did the find a conclusive problem(s) that has been fixed?
Are they making amps right now with a high fail rate relative to the competition?

Perhaps it coms down to, a great sounding amp this is way cheaper than the competition is not going to be as sturdy.

Edit: I may complain about the above, but I did buy a used 7-Pro as I liked the tone much better than a number of amps I had purchased prior.
Fingers crossed and a spare is always packed.

 

[Hopkins]

And thats fair. I was really commenting more on reliability of class D amps though. From what I've heard, that PF350/500 is a good amp and delivers on the Ampeg sound. If I didn't dig my GB I'd probably looking at a PF500. All makes have failures, what makes the difference is how a company handles those situations and it seems Ampeg is trying to make good.

All I can really say with absolute confidence is that, I have pushed my GK 700rbII to hell and back, and it never even blinked. The same thing with my Eden E300T to a lesser extent. I can absolutely with no doubt in my mind tell you that those amps are dead reliable

The only problems I have been reading about with amps recently are Class D amps, first it was the SVT-7 Pro which they seem to have gotten a handle on, and now the PF500. I'm not so sure about the other brands, but I'm sure Ampeg isn't the only one with problems. Ampeg being the biggest name the problems are going to be much more publicized than other brands.

Just from reading the forums, I would have no worries about gigging anything from Genz, Markbass, or Aguilar, But I have played all of these amps, and the sound just isn't there for me, especially MB and Aggi.

 

[Stealth Fighter]

Yes, you definitely should be able to crank it. Personally, I don't think most micros sound good when you crank them super loud (except the gain...that does sound good), but it definitely should be doable to crank the gain as hard as you want in the Ampeg micros.

Jimmy, you are joining this party late. The comments about cranking this amp were in response to one posters complaining that his PF -350 failed when running both the gain and volume at 2 o'clock. I my experience, running my '95 USA P-Bass with its volume at max into my PF-350 with all tone controls at noon and gain/master both at 2 o'clock results in extremely high output levels to the point that I would not think of running it this loud continuously, nor would I ever need to run it that loud. My point, that has caused such a stir, was simply that you couldn't judge an amps power output by knob position. FWIW, I agree that the PF-350 sounds best played loud, but there is a point when the amp has done all it can do, and in my opinion, it is pointless to try to continuously run any amp at its maximum output level. As always YMMV.

 

[arai]

My point, that has caused such a stir, was simply that you couldn't judge an amps power output by knob position.

That point did not cause a stir with me and i agree that you can't judge an amps power output by knob position.
What I didn't like is you saying that I was saying things that I was not.
For the first time I am out

 

[CnB77]

The comments about cranking this amp were in response to one posters complaining that his PF -350 failed when running both the gain and volume at 2 o'clock. I my experience, running my '95 USA P-Bass with its volume at max into my PF-350 with all tone controls at noon and gain/master both at 2 o'clock results in extremely high output levels to the point that I would not think of running it this loud continuously, nor would I ever need to run it that loud.

Whether you personally would need to is irrelevant. They make the knobs go past 2 o'clock for a reason. I can't imagine any engineer designing an amp that simply breaks when used within its design.

 

[Stealth Fighter]

That point did not cause a stir with me and i agree that you can't judge an amps power output by knob position.
What I didn't like is you saying that I was saying things that I was not.
For the first time I am out

Arai, I'm truly sorry you feel that way, but in fact, each time you said that I was putting words into your mouth I quoted your words back to you. As for your previous comment about me trolling you, a review of this thread will show that I joined in with the ninth post, well before you joined the conversation. If anything, it seems to be you trolling me.

To everyone concerned, my intent in joining this thread was to try to bring some common sense, logic, and reason to a topic that has been beaten to death almost solely on emotional anecdotal evidence. I'll refer you back to my first post: "It's obvious by now that a significant number of people are having problems with the PF 500 amps. However, there does seem to be a common thread in these reported failures. It appears that most of the people reporting failures are reporting the same failure on multiple PF 500s, while many others are reporting zero failures after several months use of the same amp. To me, this sounds statistically improbable. Why or how can this be? There must be some common dominator among these failures. Even though I am an Ampeg user and fan, I think it is long past time for Ampeg to step up and either fix or defend the amps. At the very least, they could share the real world failure rates, mean time before failure, etc., rather that pretending that these failures do not exist. Better yet, they could develop a solution or explain why the amps are not meeting the expectations of the users."

I have since been corrected by multiple posters informing me that Ampeg has stepped up to the plate and addressed these problems, to which I offer no argument. I think someone stated earlier that these issues would never be settled to everyone's satisfaction; I am beginning to agree.

FWIW, I don't think that anyone is intentionally abusing these amps. Rather, I think that they are innocently overtaxing the amps by not understandingn the gain structure and/or the limitations of the amps.

 

[Stealth Fighter]

Whether you personally would need to is irrelevant. They make the knobs go past 2 o'clock for a reason. I can't imagine any engineer designing an amp that simply breaks when used within its design.

This is true, and the reason is so that the amps can reach full power with a wide range of input levels. It is just that simple.

 

[TinIndian]

All I can really say with absolute confidence is that, I have pushed my GK 700rbII to hell and back, and it never even blinked. The same thing with my Eden E300T to a lesser extent. I can absolutely with no doubt in my mind tell you that those amps are dead reliable

The only problems I have been reading about with amps recently are Class D amps, first it was the SVT-7 Pro which they seem to have gotten a handle on, and now the PF500. I'm not so sure about the other brands, but I'm sure Ampeg isn't the only one with problems. Ampeg being the biggest name the problems are going to be much more publicized than other brands.

Just from reading the forums, I would have no worries about gigging anything from Genz, Markbass, or Aguilar, But I have played all of these amps, and the sound just isn't there for me, especially MB and Aggi.

Well, I know what you mean about the 700RBII. I have one of those as well and it was my main amp before the Genz and it's another amp that I've never had any issue with. If GK is your thing I can see why you don't go for the Genz - different animal altogether. When I moved to the Genz it's because I wanted something different from the GK. It's my bands practice room now and what I use to rehearse with.

 

[JimmyM]

Jimmy, you are joining this party late. The comments about cranking this amp were in response to one posters complaining that his PF -350 failed when running both the gain and volume at 2 o'clock. I my experience, running my '95 USA P-Bass with its volume at max into my PF-350 with all tone controls at noon and gain/master both at 2 o'clock results in extremely high output levels to the point that I would not think of running it this loud continuously, nor would I ever need to run it that loud. My point, that has caused such a stir, was simply that you couldn't judge an amps power output by knob position. FWIW, I agree that the PF-350 sounds best played loud, but there is a point when the amp has done all it can do, and in my opinion, it is pointless to try to continuously run any amp at its maximum output level. As always YMMV.

I don't disagree personally. I can't run it that hot on gigs for fear of getting us canned. I also think micros in general sound worse than other types of amps when you push them harder than you should. Most don't have much headroom past their RMS wattage and they usually go into hard limiting, which sounds yucky, or they clip in a very nasty way. But you should be able to give the gain a good thrashing at least. I do it all the time. Just turn down the master to your reasonable level. Nice and dirty but not too loud.

 

[Stealth Fighter]

I don't disagree personally. I can't run it that hot on gigs for fear of getting us canned. I also think micros in general sound worse than other types of amps when you push them harder than you should. Most don't have much headroom past their RMS wattage and they usually go into hard limiting, which sounds yucky, or they clip in a very nasty way. But you should be able to give the gain a good thrashing at least. I do it all the time. Just turn down the master to your reasonable level. Nice and dirty but not too loud.

+1 That's exactly the same experience I have with these amps.

 

[Hopkins]

Well, I know what you mean about the 700RBII. I have one of those as well and it was my main amp before the Genz and it's another amp that I've never had any issue with. If GK is your thing I can see why you don't go for the Genz - different animal altogether. When I moved to the Genz it's because I wanted something different from the GK. It's my bands practice room now and what I use to rehearse with.

I can definitely see how the GK sound does not work for everyone and every type of music.

 

[Troph]

FWIW, I don't think that anyone is intentionally abusing these amps. Rather, I think that they are innocently overtaxing the amps by not understandingn the gain structure and/or the limitations of the amps.

There seem to be at least two fundamentally different failure modes I've heard described between the PF500 and SVT-7Pro threads, neither one of which is user error:
- catastrophic fault (e.g., internal short) leading to physical damage
- protect mode cutoff requiring amplifier reset

As for the first kind, I think we can all agree that -- assuming a cabinet with proper impedance is used -- modern amplifier designs should protect themselves from catastrophic faults. You shouldn't be able to blow your amp by turning up the knobs (speakers notwithstanding). This type of failure should never be due to "innocent overtaxing", and is almost always caused by component failure.

For the second kind of fault, you could legitimately argue that the amplifier may indeed be protecting itself from damage and is therefore doing the right thing, especially if the user is pushing it too hard. Unfortunately I have experienced this type of fault first-hand in an older SVT-7Pro, and I can assure you that such cut-outs can occur at lower volume, lower gain settings, even when the amplifier has only been running a few minutes in a cool environment. There is no way this is due to overtaxing either. (Furthermore, Ampeg has apparently addressed some of these problems in later hardware revisions.)

I don't understand how the user could be responsible for either one of these failure modes. Certainly users can play loud and run up against the dynamic power limiter, but this type of temporary drop-out sounds completely different from a full cut-out.

It appears that most of the people reporting failures are reporting the same failure on multiple PF 500s, while many others are reporting zero failures after several months use of the same amp. To me, this sounds statistically improbable.

I have to disagree here. It's perfectly plausible statistically, because the distribution of "bad" units is non-uniform. Manufacturers commonly produce entire runs of bad components, or experience assembly problems which may affect large ranges of units, and the problem may not be discovered until all of those units have shipped. In those situations, it is very possible for a user to happen to get two bad units in a row. And yet if you happen to get an unaffected unit, you may not see a failure. This is quite common; I can share many anecdotes from the computer industry.

 

[arai]

Arai, I'm truly sorry you feel that way, but in fact, each time you said that I was putting words into your mouth I quoted your words back to you.

And what I was saying was not what you were saying I was saying in each case.

 

[Stealth Fighter]

There seem to be at least two fundamentally different failure modes I've heard described between the PF500 and SVT-7Pro threads, neither one of which is user error:
- catastrophic fault (e.g., internal short) leading to physical damage
- protect mode cutoff requiring amplifier reset

As for the first kind, I think we can all agree that -- assuming a cabinet with proper impedance is used -- modern amplifier designs should protect themselves from catastrophic faults. You shouldn't be able to blow your amp by turning up the knobs (speakers notwithstanding). This type of failure should never be due to "innocent overtaxing", and is almost always caused by component failure.

For the second kind of fault, you could legitimately argue that the amplifier may indeed be protecting itself from damage and is therefore doing the right thing, especially if the user is pushing it too hard. Unfortunately I have experienced this type of fault first-hand in an older SVT-7Pro, and I can assure you that such cut-outs can occur at lower volume, lower gain settings, even when the amplifier has only been running a few minutes in a cool environment. There is no way this is due to overtaxing either. (Furthermore, Ampeg has apparently addressed some of these problems in later hardware revisions.)

I don't understand how the user could be responsible for either one of these failure modes. Certainly users can play loud and run up against the dynamic power limiter, but this type of temporary drop-out sounds completely different from a full cut-out.


I have to disagree here. It's perfectly plausible statistically, because the distribution of "bad" units is non-uniform. Manufacturers commonly produce entire runs of bad components, or experience assembly problems which may affect large ranges of units, and the problem may not be discovered until all of those units have shipped. In those situations, it is very possible for a user to happen to get two bad units in a row. And yet if you happen to get an unaffected unit, you may not see a failure. This is quite common; I can share many anecdotes from the computer industry.

First point: No one in this thread has mentioned the 7 Pro, to my knowledge.

"- catastrophic fault (e.g., internal short) leading to physical damage"

No argument at all with this point, except that this type of failure seems to be in the minority of reported PF 500 failures

"- protect mode cutoff requiring amplifier reset"

Again, this thread has not included the SVT 7 Pro, so any argument made for or against that amp is irrelevant to this discussion. I am referring mainly to the "cutting out" issues (including possibly related component failures) reported with the PF 500, which I think are the result of the amp protection circuits switching on to protect the amp from overstress caused by driving the amp too hard. As others have stated, the limiter in these amps is harsh, to say the least.

We will have to agree to disagree on the plausibility of these recurring failures. From my experience (eighteen years in quality control and manufacturing with three major electronics manufacturers), the vast majority of "batch related" failures are discovered well before the entire production run is completed. A high volume manufacturer can produce thousands of units in a single production run. The first company I worked for produced around 800 TV sets per day on each of at least five assembly lines. I personally performed overnight burn in and one-week life testing on samples of each of these assembly lines, as well as 500-hour burn in tests that were conducted at 40 degrees C and high humidity. I assure you very few sets left the factory with defects that we did not know about. No doubt, some defective units slipped through the cracks, but, even so, we consistently ran defect rates below 3%, and that was when solid-state TV technology was in its infancy. Many of the reported PF 500 "cut out" failures have spanned two or more revision levels, even when reported as repeat failures by the same user. This in no way that I am aware of represents a batch related problem.

In retrospect, I guess we will respectively have to agree to disagree on most of what we have said.

 

[Stealth Fighter]

And what I was saying was not what you were saying I was saying in each case.

Arai, we could just let this thing go, or we could continue with this circular firing squad, which ever you prefer. I vote for letting it go. What do you say?

 

[alaskaleftybass]

The more I read these horror stories the more I love my old Peaveys.