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Amplifiers, effects, pickups, electronic components, wiring, etc.

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Jack Stoner
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Post by Jack Stoner »

I've seen and experienced this many times with My Nashville 400 and an older Session 500. However, it's not just the Peavey's or possibly solid state amps, as our lead player had the same problem with a Fender Tube Amp.

I wonder if the new Peavey amps with the switching power supply exhibits the same thing.
Mike Brown
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Post by Mike Brown »

Yes, any amplifier will lose volume and/or dim the power light when powered up under low voltage situations. I think that everyone who has experienced a "dimming of their home lighting" knows that there was a problem in power lines that causes this. This is the same symptom when your amp power light dims and you lose volume/gain, ie; low voltage is usually the culprit.

A digital power amp is even more sensitive to low voltage. An analog amp will start having problems at approximately 100 volts which puts stess on the power transformer and a digital powered amp design will start malfunctioning somewhere around 105 volts, depending on the design of the power supply.

I've played in many a cinder block honky tonks through the years and have encountered the low voltage situation. I would hate to imagine what would happen if professional musicians "didn't" have a power requirement in their riders. I'm sure that if their show is interrupted, it doesn't make them look good.

I've always found that it is best to check out power availability prior to a performance. Make sure that the sound and lighting systems are on separate circuits and that the total amperage required does not exceed that of the breakers.

The fact that two different Nashville 400's were used and that both exhibited the same symptoms should be an indication that there is a voltage problem for that application.
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Richard Sinkler
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Post by Richard Sinkler »

Many years ago, when playing both steel and keyboards, I purchased a Tripp Lite power conditioner. This will stabelize the voltage for you in most cases. My main reason for buying it was that I played a lot of outside gigs where power was very questionable. The power would drop low enough that my synthesizers would re-boot during the middle of a song. They would come up to their "default" program which wasn't necessarily what I wanted. This unit also stopped the breaking up problem described above. Unit is a little pricey, but I felt it was good insurance and a good investment. I'm not sure, but I think there are other less expensive units available now, maybe from Furman Sound.
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Jack Stoner
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Post by Jack Stoner »

The inexpensive units (less than a couple hundred bucks) in most cases will not compensate for low AC line voltage. An "autotransformer" is needed to adjust for the low AC line voltage.

A "power line conditioner" may filter some AC line noise and regulate some small line variations, but if the AC line voltage is only 100 or 105 VAC, a conditioner will not boost it to 115VAC.
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Blake Hawkins
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Post by Blake Hawkins »

Hey Bob...ever lifted one of those Sola Transformers? Image
I don't know about the new ones...but the old ones had lotsa iron and were very heavy.
Blake