Mark II C+ Pre Amp Out / Power Amp In on bottom of chasis ??

[dino2sf]

If i want to slave my mark II C+ preamp into my Mark V power amp........... if I use the Pre Amp Out / Power Amp In on bottom of chasis of the C+ into the effects return of the Mark V.......
Does the C+ need a speaker load ? is the signal never hitting the power section of the C+?

Thats the way I understand it to be according to the manual :

Always run the Boogie with a speaker or load resistor (8 to 20 ohms, 50 watts) if you
are using the Slave Out.

A Pre Amp Out-Pwr Amp In jack is located on the bottom of the chassis and
provides access to the junction of the preamp and the output power amp. With it, another Boogie can be
linked up (Slave Out of the first amp to Pwr Amp In of the second), or it can allow you to use the Boogie
as a preamp only.


I hope this makes sense...

Also if I am only using the C+ as a preamp...would it still work with no power tubes in it?

Thanks

 

[dodger916]

If you need to take the amp off stand-by to use the preamp, then I'd say keep tubes in and speaker (or resistor) attached.

I'm curious as to why you wouldn't just keep the tubes in and the speaker attached anyway. Or get a Studio Pre and run that into the power amp. It's much more portable than a C+.

 

[stokes]

When you utilize the "pre-out" jack,the signal is re-directed and never hits the output of the amp.As Frank said,just leave all the tubes and speaker connections.

 

[stokes]

When you utilize the "pre-out" jack,the signal is re-directed and never hits the output of the amp.As Frank said,just leave all the tubes and speaker connections.

 

[dino2sf]

Thanks for the input.......

The reason I dont want to have the speaker plugged in is that the speaker cab is running out of the Mark V speaker output. The C+ is a head.
As far as the tubes I just figured if they didnt have to be in the Mark IIC+ I would pull them out and perhaps make them last a little longer.
Ive decided to use my Weber Mass attenuator on Load setting on the C+ just incase (even though.... it seems if the signal never hits the power section then a speaker load is NOT needed
but better safe than sorry)

Im just kinda playing around with stuff I have to see what kinda tones I can get. Ive actually got the C+ preamp running into the Mark V power section (6L6 powered) to a 2x12 Recto Cab with EVM 12L's then im running the slave out of the Mark V into a G Major 2 then stereo out to a Mesa 2:50 Stereo power amp with el34 power tubes driving left and right Theile cabs with EVM12L's for a Wet/Dry/Wet setup (I know ...Im a freak but its fun and I have all the gear so might as well use it). So far this setup KICKS ASS !! Sounds way better than using the Mark V on its own also sounds WAAAYYY
better than using the C+ on its own. Not hauling to gigs so its fine for me at home.

Extra bonus I just discovered..
Selecting channel one , two or three on the Mark V footswitch gives me 3 different tones
(kinda weird since Im bypassing the Mark V preamp..... I guess the multi-watt settings and rectifier settings on each channel are doing this)
plus the boost function on the Mark V works as normal.

Its like a 6 channel C+ with boost switch running 6L6 and EL34 Power sections
So far Im Loving it

Thanks Again

 

[stokes]

You'll be okay,the only reason I thought it best to leave the speaker connected was that if it was a combo and you tried to use it as such and forgot to re-connect the speaker......

 

[DM47]

When you utilize the "pre-out" jack,the signal is re-directed and never hits the output of the amp.

I'm curious about this statement. My IIC has this jack on the bottom of the chassis and it is not wired to work this way. It's just a point to tap into, or out of, the circuit. It does not interrupt the signal in any way, thus a load must be connected if the power tubes are installed. Mine uses just a plain ol' Switchcraft 11 jack.
Maybe the IIC+ uses a switching jack arrangement for interrupt?

 

[stokes]

Yes,it should be a switching jack.

 

[Henz]

I'm curious about this statement. My IIC has this jack on the bottom of the chassis and it is not wired to work this way. It's just a point to tap into, or out of, the circuit. It does not interrupt the signal in any way, thus a load must be connected if the power tubes are installed. Mine uses just a plain ol' Switchcraft 11 jack.
Maybe the IIC+ uses a switching jack arrangement for interrupt?

I just found this old thread. I've had my C+ for many years and for the first time I finally plugged into the preamp out jack and fed it to my 2:90. Since its just accessing the preamp before the phase inverter based on schematic, I assumed that I would not get any signal to my speaker hooked to the C+( mute the signal from going to PI. But I was. And I was getting signal to the 2:90. I've always used the slave out to power my 2:90. It just pretty much does the same thing, maybe sounded A lil different. So, what am I mis understanding here? I've been inside chassis many times and its just a mono 1/4 plug with tip going to EQ then to PI. Thanx!

 

[Jay Omega]

I just found this old thread. I've had my C+ for many years and for the first time I finally plugged into the preamp out jack and fed it to my 2:90. Since its just accessing the preamp before the phase inverter based on schematic, I assumed that I would not get any signal to my speaker hooked to the C+( mute the signal from going to PI. But I was. And I was getting signal to the 2:90. I've always used the slave out to power my 2:90. It just pretty much does the same thing, maybe sounded A lil different. So, what am I mis understanding here? I've been inside chassis many times and its just a mono 1/4 plug with tip going to EQ then to PI. Thanx!

The preamp out jack is located after the FX loop recovery stage where the master volume shunt and EQ input come together. The tip of the jack is the EQ input, so anything you connect there will be in parallel with your power amp. The jack does not break the circuit, it’s a plain old TS jack, so your EQ and beyond is still active if you have something plugged in.

Hopefully this makes sense!