I emailed the shop that I bought it from. At first they said that the cab did not match the amp and that it was going into protect mode because of this. But I don't think he realized that the amp is 8ohm and 4ohm capable. Once I explained in detail what was happening, what my settings were etc, he agreed that it does sound suspect and that it should not go into protect mode with volume at 2 and gain at 3. He is sending Ampeg an email and going to let me know what they say.
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Ampeg pf-350 and thermal protection
- Thread starter versicolor
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- ampeg pf-350 protection
I'm going to try it with the 410 when I get home from work today.
That 2x10 probably isn't giving you much more volume anyway since you're splitting the load with it connected. The PF350 puts out 250W @ 8 ohms. I'd rather push 250 into the 4x10 then divide 350 into mismatched cabinets. So I agree with the others though, start with the 4x10 and eliminate the easy things.
I push the power section on mine, usually with the volume around 7 into an 8 ohm load. It hasn't ever cut out on me. I've run it that way using the existing preamp, and also with an external into the effects return utilizing just the power section. I can't recall if I engage the limiter.
Give it a whirl with the 4x10 and report back.
I push the power section on mine, usually with the volume around 7 into an 8 ohm load. It hasn't ever cut out on me. I've run it that way using the existing preamp, and also with an external into the effects return utilizing just the power section. I can't recall if I engage the limiter.
Give it a whirl with the 4x10 and report back.
Ok the 2x10 was indeed the culprit. The amp does not cut out with just the 410. I can run the 210 with it if I dont slap and I can run it with the limiter engaged and it doesnt cut out. That 210 coupled with the 410 sounds much louder and more punchy. But I think with it being only 100 watts the amp just doesn't like that combo if I'm going to play at loud volumes.
Seems odd to me that I can't run both of these cabs at once with this amp. I wonder why that is. I just don't have the knowledge of this stuff to be able to comprehend it. So if I were to get a higher wattage second cab I wonder if it would still cut out. Say the svt 210?
- Feb 12, 2006
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- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Now that we have (reasonably) determined that the symptoms appear to be based on the total impedance being too low and causing the protection circuit to protect the amp, I would investigate each cabinet to be sure it really is what you think it is. Do you have a digital multi-meter?
My initial hunch is that the 410 MAY be a 4 ohm cabinet, but other possibilities are that the 210 is not 8 ohms, or that either of the cabinets has a substantial region of sub-nominal impedance (causing the amp to think the total load is less than 4 ohms)
This is how basic troubleshooting of a problem like this is done. The odds are that you will get a more accurate view of the problem which makes it more likely that you get a good solution.
My initial hunch is that the 410 MAY be a 4 ohm cabinet, but other possibilities are that the 210 is not 8 ohms, or that either of the cabinets has a substantial region of sub-nominal impedance (causing the amp to think the total load is less than 4 ohms)
This is how basic troubleshooting of a problem like this is done. The odds are that you will get a more accurate view of the problem which makes it more likely that you get a good solution.
I do have a multi meter. But I would need instructions as to how I determine what ohms each cab is.
Get a Rumble V3 210, sound great-700 Watts, if you like the 210/410 combo. I'll bet a pair of the Ampeg 410's would probably put out some awesome sound.
- Feb 12, 2006
- 61,031
- 5
- 220,922
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Set the scale to ohms, plug into your speaker and at the amp end of the cable measure the resistance. It's a lot easier of the amp end of the cable is a 1/4" plug (measure from tip to sleeve). Do this in a quiet room, helps the meter settle better.
No a higher wattage rating on the cab wouldn’t cause that. Please check all your cables and follow agedhorse’s troubleshooting advice.
FYI I have a PF350 and regularly run it through 2 x Ampeg 210AV cabs (so 4 ohm load) with the gain and master both at 5 (12 o’clock). I’ve had the master up to 8 at a gig.
I dig in fingerstyle and most of my basses have hot outputs.
Depending on the bass I’m playing I may turn up the bass EQ a bit to 6 or 7. I’ve never had my PF350 cut out.
If an amp has a limiter, I say use it. The limiter is your friend and may save your speakers.
I have trouble understanding why you'd want to deliver the same power to a 210 as you would with a 410, especially when the 210's only rated at 100 watts. Unless all the speakers are 16 ohm, each speaker isn't getting the same power. I'm guessing all are 16 ohm, but.....?
None of this sounds at all right to me. I think you just might have a faulty head. I have a pf-350 that I've gigged with 2-3x/month for the past three years going into a 4ohm SVT-412HE with the volume cranked over past 3 o'clock every single time. I have not treated it well, either - I just throw it in a backpack with a bunch of other stuff, drop it, spill beer on it. I've really abused the thing and it's been 100% "child proof" for me - most reliable piece of electronics I've ever owned. Based on my experience, there's just straight up gotta be something broken with your head. I see no reason why you couldn't procure another one, super-cheap used, and have a hassle free experience in line with my own.
Turn your pre down to 1:00 0r 12:00. Use the limiter. Try each cabinet separately. Maybe 2 x 210's would work better together. Might not be as loud as the 410 but they would be more evenly matched.
And...........................
Stop slapping!
And...........................
Stop slapping!
It might also be reasonable to consider that the 2x10 could be damaged considering you've been sending it a load that it's not designed to handle. If your head is splitting the 350 watts, then you are potentially sending 175 of them to a 100 watt cabinet (and a very cheaply designed one in that). I'm a big Ampeg guy, but those MC stacks were really for light duty bedroom volume.
Maybe @agedhorse can comment further on this.
Maybe @agedhorse can comment further on this.
I only hooked up the 210 because i had it just laying around and I thought...i wonder what that little 210 would sound like with the 410. Turns out it really sounded awesome. I know its not ideal but it sounds so good with it that I want to continue to use it if I can.
