pre-amp to power amp...?

[blue]

morning folks,

i'm not 100% sure how to do what i want to do.  i have several heads here, all with effects loops.  i would like to put the preamp of one head through the power amp of another, via the first head's effects out into the second head's effects in.  now, i know this will work fine, i've put standalone preamps through with no issues.  what i'm not sure about is how to make sure the two heads are connected up safely.  i don't want any sound from the first head, but i assume it will still need a speaker load, as the guitar signal will be passing through it.  it may head out through the effects out, but i imagine it's still going through the power section too, or does a series loop mean it doesn't?  can i just connect an attenuator for safety, with no speaker attached, and turn down the amp's master?

a pretty simple little problem, but i don't want to proceed until i'm sure i won't be doing any damage.  thanks for any help you guys can provide :)

[Dmoney]

you're right. with a series loop, when you plug into it, you should be breaking the connection from preamp to poweramp.
You need the dummy load because even if you disconnect the preamp, with the amp off standby the power valves will be 'working' as normal and they would want to see a load (speaker, attenuator). there are probably ways to get around the attenuator.

what amps are you joining together? 

[Twinfan]

I think he wants to run his AFD100 through the EL34s in the YJM  ;)

[Dmoney]

I think he wants to run his AFD100 through the EL34s in the YJM  ;)

I was thinking that might be the case.

[blue]

Thanks Dmoney, so i do need the attenuator connected to the output to protect the unused power amp? i would really rather not blow anything up!

Dave, indeed, that is what i want to try :)  although now that i've thought of that i want to try a couple of other amps through it too.  could find some interesting results.

[Twinfan]

You need both heads connected to cabs, but the pre-amp only head will not produce any sound  :)

[Dmoney]

Thanks Dmoney, so i do need the attenuator connected to the output to protect the unused power amp? i would really rather not blow anything up!

That is correct. if you have an attenuator that has a dummy load setting (like a hotplate) then you're all good. I had another idea but that way is the easiest, and if you do it this way you don't need the extra cab.

When it comes to slaving, some amps are designed to do it more easily than others.

[blue]

excellent, thanks lads, i'll be giving all that a go this evening then  8)

[HTH AMPS]

speaking of load boxes, I made one recently - 16 ohm, 200w.  could've easily added a line out for some EVH action straight into another power amp (or effects return of another amp).

[Frank]

You need both heads connected to cabs, but the pre-amp only head will not produce any sound  :)

Depends how the FX loop is wired, often it's only the power amp in that socket breaks the connection