Musicians Roadhouse

Steve Dawson wrote:You can have your amp on standby with no load connected, this is perfectly safe. You can also have your amp fully turned on with no load connected as long as there is no signal passing through it ie. guitar plugged in and played by somebody. The potential for damage is when the OP Tx tries to drive signal into an open circuit (no load).

Now thats something I didn't know!! I thought if it was on, that was a bad thing, guitar or no guitar!

CooL!

Here's another one...

If you remove the two outside poweramp valves (tubes) from a 100w amplifier, you can use it as a 50w amp.

Over to you Steve

mety wrote:Here's another one...

If you remove the two outside poweramp valves (tubes) from a 100w amplifier, you can use it as a 50w amp.

Over to you Steve

This is definately a NO NO on the 100 Watt Vintage Modern. The HT (B+) on this amp is very high; - approx 530VDC and this is about as high as the KT66s will live happily at. If you remove the two outer or inner output valves the HT rises by about 20V due to less current getting pulled out of the Power Transformer and therefore less loading. The output valves will more than likely arc over causing damage to themselves as well as other components in the power stage.

A 100W amp is designed to be just that. not 50W. Everything is optimised to work together efficiently - output valves, output transformer primary winding etc.

I wouldn't advise anybody to do this to any amp!

GuitarRich wrote:

Steve Dawson wrote:You can have your amp on standby with no load connected, this is perfectly safe. You can also have your amp fully turned on with no load connected as long as there is no signal passing through it ie. guitar plugged in and played by somebody. The potential for damage is when the OP Tx tries to drive signal into an open circuit (no load).

Now thats something I didn't know!! I thought if it was on, that was a bad thing, guitar or no guitar!

CooL!

It is still not advisable to have no load connected when the amp is fully turned on

SteveD wrote:It is still not advisable to have no load connected when the amp is fully turned on

Definitely - but it is nice to know that if you do be stupid (I've nearly done it so many times! lol - don't plug in after a few beers! :oops: ) theres a chance you wont kill your amp if you catch it quick enough!

GuitarRich wrote:

SteveD wrote:It is still not advisable to have no load connected when the amp is fully turned on

Definitely - but it is nice to know that if you do be stupid (I've nearly done it so many times! lol - don't plug in after a few beers! :oops: ) theres a chance you wont kill your amp if you catch it quick enough!

Good Lord yeah, we've all been there :P I even thought I'd blown my amp once when the speaker cable wasn't in and then I plugged it in to NO sound .... 15 solid minutes of freaking out and then realising I'd accidentally pulled the guitar cable out by about 2 mm too !!!! lol

GuitarRich wrote:

SteveD wrote:It is still not advisable to have no load connected when the amp is fully turned on

Definitely - but it is nice to know that if you do be stupid (I've nearly done it so many times! lol - don't plug in after a few beers! :oops: ) theres a chance you wont kill your amp if you catch it quick enough!

Yeah, that is cool to know. I was trying out a dsl50 recently and the sales guy pulled out the speaker jack and plugged it into another cab while the amp was still on and I remember thinking what a f@#king idiot :)

Atlest youre some one who when confronted with facts against their beliefs actually goes and checks the facts and changes opinion/belief accordingly...there is nothing to be ashamed about that...its those who confronted with truth still choose to believe the alternative.

keiths_marshall wrote: Yeah, that is cool to know. I was trying out a dsl50 recently and the sales guy pulled out the speaker jack and plugged it into another cab while the amp was still on and I remember thinking what a f@#king idiot :)

When I was demoing VMs at Guitar Center I tried it through about 4 different cabs. The salesguy did the same thing and I thought the same thing.