BillFitzmaurice.info

...but how do i monitor the voltage from my amplifier?

Just like daisy chaining cabs, just parallel the voltmeter. Basically, just attach the voltmeter to the banana plugs on the back of the amp.

EDIT: and just in case, yes, you can measure without the speaker being hooked up.

SeisTres wrote:
EDIT: and just in case, yes, you can measure without the speaker being hooked up.

I wouldn't recommend running the amp up without a load/speaker. Im sure it can be done safely on most amps, Iv just had an amp blow up because of it.

One time I blew one side of my lem 2.420 when i was measuring the voltage@50hz to set my limiters. Something started oscillating inside the amp and it blew 3 ouput transistors.

hmmm.....never heard of that happening on a solid-state amplifier. Was that a tube amp that blew up on you?

petegt wrote:
One time I blew one side of my lem 2.420 when i was measuring the voltage@50hz to set my limiters. Something started oscillating inside the amp and it blew 3 ouput transistors.

Is that a tube amp? googled it and really couldn't find anything save a few things about a transformer and then univox came up.

I think the biggest risk is that you either accidentally cross the probes when measuring (which will short the output) or have the meter set to measuring amps. An amp that blows because there's nothing plugged in deserves to blow. It certainly isn't something I'd like to use in a mobile setup...

But this inspired me to build a banana to speakon adapter. Bananas go in the meter, and then just plug the Speakon into the output of the amp or the daisy socket on a speaker.

SeisTres wrote:

petegt wrote:
One time I blew one side of my lem 2.420 when i was measuring the voltage@50hz to set my limiters. Something started oscillating inside the amp and it blew 3 ouput transistors.

Is that a tube amp? googled it and really couldn't find anything save a few things about a transformer and then univox came up.

No solid state. So hard to find info on this amp. 8 ohms RMS 2X240W 4 ohms 2X420W RMS with 2 toroidal transformers http://www.wikizic.org/LEM-2-420/gallery-1.htm.I'd never heard of it happening before. I did use banana plugs into the binding posts so no danger of shorting. Maybe just bad luck.

petegt wrote:Maybe just bad luck.

Probably. With no load there's nothing to cause any oscillation. The other possibility is the meter. Meters typically have very high impedance, so they're essentially not a load, but you never know.