Just curious Joel - what kind of bass were you using when it was cutting out ? Active ? Passive ? Not that it would make much difference with a defective unit, just wondering ?
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Ampeg PF350/500 Part V
- Thread starter Chef
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Just curious Joel - what kind of bass were you using when it was cutting out ? Active ? Passive ? Not that it would make much difference with a defective unit, just wondering ?
Only passive basses in my house. P-Bass when it was cutting out on the gig, and a Jazz bass in the bedroom did the same thing.
first let me say that I'm sorry you are having issues with your PF500. Amp failures are always a pain to deal with. I have a PF500 myself, and have gigged it for several months now with no issues. I don't push it at all with the 8ohm PF115HE cab, so my experience is not directly related to your 4ohm experience.
I am most interested in your output analysis of the amp. I agree with JimmyM that all you have currently tested is the output of a bad unit. I am most interested in seeing how your replacement unit scopes out, and what the reaction will be if a new/good unit still scopes out at 380w. I personally won't like my PF500 any less, but it will be instructive to see what the reactions will be. Please let us know.
Good luck with the new PF500.
When mine cut out at a gig I had it checked out at an authorized service center and they told me it was "operating up to spec". I did not ask any details - but I assumed this meant it can put out about 500 watts.
As the owner of a PF-500, I thought I would be able to use a padded laptop bag as a gig bag for it, but I tried a few laptop bags that I already have and none were a good fit. Has anyone found a specific laptop bag that is a great fit for the PF500? If so, please share the make and model for the bag. Preferably one with some padding for protection.
Forgive me if this has been discussed -- I searched but didn't find an answer.
Thanks.
Forgive me if this has been discussed -- I searched but didn't find an answer.
Thanks.
I bought one at Dunhams sporting goods that works pretty well. I posted about it in one of these threads some time ago - maybe a year or more. Was around $20 and well built.
I have the Gator Deluxe Padded Music Gear Bag, 15x15 inches, item # 545857000000676 from Musicians Friend, $39.95. It is well-padded and works great; plenty of room for cables in front, easy to carry, and perfect for the PF500.
Using the pf500, pf210he and pf115he rig tonight. First time using it all at normal band volumes, didn't get a chance to rehearse with it. I'm just crossing my fingers that it won't cut out with the new 4 ohm load. Ive had it for about half a year with just the 210 and never had any problems. 
Will post pics, regardless.
Will post pics, regardless.
My "defective" PF-500 made it through last nights super loud blues jam using an 8-ohm house provided 80's GK 410. Same P-Bass. Same Signal Chain. Even survived some VT-Bass gain additions ("Flat" setting + Drive @9 + Gain 2db above unity). Just fine, no cut outs. replacement is coming in the mail as we speak.
Comp: 7:30-8
Pregain: 2-2:30
Ultra Low: On
Ultra Hi: Off
Bass: 1:30
Mid: 1:30
Mid Select: 4
Treble: 2:30
Main: 2-2:30
My tech said that too when it put out 380w. He stated after looking at the Loud specifications that they measured power at 500w @ 5% THD. We were measuring 380W @ Less than 1%. To be honest, the 500w Spec @ 5% THD is pretty bloated looking now that I think back upon it. Who else in pro audio uses 5% THD to specify power other than "Peak"?
Looks like I'll owe my tech a beer and/or some other party favor.. I'll see what I can do
Comp: 7:30-8
Pregain: 2-2:30
Ultra Low: On
Ultra Hi: Off
Bass: 1:30
Mid: 1:30
Mid Select: 4
Treble: 2:30
Main: 2-2:30
My tech said that too when it put out 380w. He stated after looking at the Loud specifications that they measured power at 500w @ 5% THD. We were measuring 380W @ Less than 1%. To be honest, the 500w Spec @ 5% THD is pretty bloated looking now that I think back upon it. Who else in pro audio uses 5% THD to specify power other than "Peak"?
Looks like I'll owe my tech a beer and/or some other party favor.. I'll see what I can do
& how did u like the sound of yr "defective"unit at this "super loud" gig? Did it sound good as well as handle the gig?
This ain't pro audio 
And besides, that's not a lot of distortion for bass amps being cranked that hard. And I've said this before but I think it bears repeating...just like you couldn't crank regular solid state amps super hard and get the same result as tube amps, you're not going to get the same result as regular solid state by cranking micros super hard, either. Micros by and large don't have a lot to give you after they hit their top RMS wattages like regular solid state and tube. For most situations, a 500w micro is more than enough. But if you need that kind of power where you have to crank a 500w micro up all the way, you're better off sucking it up and getting something with more wattage or going big iron. I've played a lot of micro heads and I've yet to play one that liked being super cranked. Either they limit really hard, they distort in the nastiest of ways, or they cut out...or any combination thereof. All of them that I've played for sure. Except for the 7 Pro...and I don't dare crank that one all the way up
So if you're looking use a micro, be puke-inducingly loud, AND you want super clean headroom, overbuy wattage.
And besides, that's not a lot of distortion for bass amps being cranked that hard. And I've said this before but I think it bears repeating...just like you couldn't crank regular solid state amps super hard and get the same result as tube amps, you're not going to get the same result as regular solid state by cranking micros super hard, either. Micros by and large don't have a lot to give you after they hit their top RMS wattages like regular solid state and tube. For most situations, a 500w micro is more than enough. But if you need that kind of power where you have to crank a 500w micro up all the way, you're better off sucking it up and getting something with more wattage or going big iron. I've played a lot of micro heads and I've yet to play one that liked being super cranked. Either they limit really hard, they distort in the nastiest of ways, or they cut out...or any combination thereof. All of them that I've played for sure. Except for the 7 Pro...and I don't dare crank that one all the way up So if you're looking use a micro, be puke-inducingly loud, AND you want super clean headroom, overbuy wattage.
It sounded great. Got a comment from the guy who matters that it sounded well up to par.
This ain't pro audio
So if you're looking use a micro, be puke-inducingly loud, AND you want super clean headroom, overbuy wattage.
Not to compare apples to oranges, but other brands may choose to rate their designs at less THD. What I was saying was, when I was watching the max power rating being found (at 1Khz sine) we made sure that the waveform was less that 1% THD. This was 380w (thereabouts). Over that and the THD became noticeable on the oscilloscope display. What I was stating was that Ampeg's rating was at a higher THD than my test with tech. Therefore; it being closer to 5% THD to me it seems more like a peak rating and not one that one would want to sustain for any long period of time.
The difference between 400w and 500w is going to be insignificant anyways. I agree with everything you said about amplifier sizing and application
You'd be surprised. Most companies don't list %THD with their ratings. Read some of the BGM tech reviews, many - and especially these micro heads - hit their rated wattage at 5% with plenty of burst power to spare using a 1k wave.
The GK MB800 was 806 at 5% with a burst of 1000 watts
Ampeg SVT-7 was 763 at 5%, burst at 934 watts
Orange Terror Bass was 519 at 5%, burst at 972 watts
GK Fusion 550 was 219 at 1% and 568 at 5%
Mesa M6 Carbine was 610 at 5%
Don't get me wrong, they also had a fair number of amps that hit their rated power at 1% (including the ampeg micro-vr, markbass, hartke, etc), but I'm just saying it's not uncommon at all to rate at 5%.
Dymond- said:Using the pf500, pf210he and pf115he rig tonight. First time using it all at normal band volumes, didn't get a chance to rehearse with it. I'm just crossing my fingers that it won't cut out with the new 4 ohm load. Ive had it for about half a year with just the 210 and never had any problems.
Will post pics, regardless.
I'm curious to see what you think of that stack. Let us know how it goes.
Sounded great. With the 115 on the bottom, the lows seem to come at your from every angle (off the walls, I guess). Its my first stack Ive had so I have very little experience, but I couldn't seem to find anything wrong with mixing the 115 and 210. You get the best of both worlds, the punchiness of the 210 and the deep lows of the 115.
The extra headroom was awesome. The single 210 could have gotten the same volume I was running last night, but I would have had to roll off the bass to keep the lows from getting fuzzy and the head would have been shaking like crazy. The extra wattage handled it perfectly, didn't have to roll off anything so I was able to keep my tone.
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