#1
Having only owned combos, I was wondering if it's true that you have to connect a guitar head to a cab/ load box prior to switching it on, otherwise you might fry it in some way.

Is this the truth?
#2
Quote by Chargrill3d
Having only owned combos, I was wondering if it's true that you have to connect a guitar head to a cab/ load box prior to switching it on, otherwise you might fry it in some way.

Is this the truth?

Yes it is a very real possibility. the OT (output transformer) needs a load like a speaker or attenuator
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#4
If it has a tube power section then yes. The output transformer of a tube amp converts internal high voltage/low current to external low voltage/high current. If you don't have a load on the speaker output then the internal high voltage can spike enough to cause electrical arcing, which leads to failure.

Solid state amps don't have an output transformer because they are already low voltage/high current. Therefore a load and high voltage arcing is not an issue.
#5
Quote by Chargrill3d
Having only owned combos, I was wondering if it's true that you have to connect a guitar head to a cab/ load box prior to switching it on, otherwise you might fry it in some way.

Is this the truth?

Yes, unless your amp head has a built-in dummy load like my Laney IRT Studio
#7
I'm going to stick something on the guitar head - 'do not turn on till load box connected'
#8
Quote by Chargrill3d
I'm going to stick something on the guitar head - 'do not turn on till load box connected'

well just turning the amp on will not kill it, it is trying to play your guitar through it without a load is when all the bad stuff happens
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#9
Quote by Robbgnarly
well just turning the amp on will not kill it, it is trying to play your guitar through it without a load is when all the bad stuff happens


Really? I was always told that even turning it on was bad. I know little to none about amplifier electronics though.
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#10
Quote by Most_Triumphant
Really? I was always told that even turning it on was bad. I know little to none about amplifier electronics though.

It's not good for it, but for a short period you should be fine (a min). It is when there is a signal to be amplified that problems will really happen

But it is wise to error on the side of caution.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
Last edited by Robbgnarly at Oct 22, 2015,
#11
Quote by Most_Triumphant
Really? I was always told that even turning it on was bad. I know little to none about amplifier electronics though.


+1

The power transformer would still be on, they can fry too.
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alright "king of the guitar forum"


Quote by trashedlostfdup
nope i am "GOD of the guitar forum" i think that fits me better.


Quote by andersondb7
youre just being a jerk man.



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#12
Quote by trashedlostfdup
+1

The power transformer would still be on, they can fry too.


Nope. Sorry. Robb's right on this one.

As an example I believe it was Ippon who had one of his many "girlfriends" leave an amp on and not connected to a load for several days (a Soldano SLO IIRC). No signal input and no damage.

An OT shouldn't fail unless there's sufficient overvoltage to cause an insulation failure, and that usually requires an input signal.
“Ignorance more frequently begets confidence than does knowledge.”
Charles Darwin
#13
Quote by Arby911
Nope. Sorry. Robb's right on this one.

As an example I believe it was Ippon who had one of his many "girlfriends" leave an amp on and not connected to a load for several days (a Soldano SLO IIRC). No signal input and no damage.

An OT shouldn't fail unless there's sufficient overvoltage to cause an insulation failure, and that usually requires an input signal.


My mistake. Learned something new.
WTLT 2014 GG&A

Quote by andersondb7
alright "king of the guitar forum"


Quote by trashedlostfdup
nope i am "GOD of the guitar forum" i think that fits me better.


Quote by andersondb7
youre just being a jerk man.



****** NEW NEW NEW!
2017-07-07 2017-07-07 Update and a Chat On Noise Constraints *** NEW FRIDAY 7/7
2017-04-13 RUN AWAY from COMPUTERS!!! TCE? RANT ALERT!!!
2017-03-02 - Guitar Philosophy 1001- Be Prepared For the Situation (Thursday 2017-03-02)
2017-02-21 How to Hot-Rod the Hell of your Stratocaster for $50! (Tuesday 2017-2-21)
Resentments and Rambling from a Guitar Junkie
---> http://trashedengineering.blogspot.com/
#14
Quote by trashedlostfdup
My mistake. Learned something new.


It's not something one would want to test....

I suspect telling everybody that it will cause the world to end is because if you tell them the truth invariably some knothead is going to do it just because he can, and when it fails because he forgot and plugged into it and started wailing, then he comes back and complains that the advice was no good!!

Ain't nobody got time for that...
“Ignorance more frequently begets confidence than does knowledge.”
Charles Darwin
#15
Quote by Arby911
Nope. Sorry. Robb's right on this one.

As an example I believe it was Ippon who had one of his many "girlfriends" leave an amp on and not connected to a load for several days (a Soldano SLO IIRC). No signal input and no damage.

An OT shouldn't fail unless there's sufficient overvoltage to cause an insulation failure, and that usually requires an input signal.

She was trying to play guitar for a whole week. She heard the amp head making sounds every time but not from the cab, because it wasn't connected.

For a whole week!
#16
Quote by Ippon
She was trying to play guitar for a whole week. She heard the amp head making sounds every time but not from the cab, because it wasn't connected.

For a whole week!



Poor intellect, awesome design!!
“Ignorance more frequently begets confidence than does knowledge.”
Charles Darwin