Connection Options - Studio Pre into 50 50 Power into 4x12 v30 Recto Cab

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mealworms

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I've read the manual for both and most everything makes sense to me. I want to double check here and see if I have the options I think I have.

There's a stereo 4ohm + 4ohm connection on the cab and also single mono 8ohm connection.

The cab must be two pairs of 8ohm V30s each for each channel, each pair wired in parallel for the 4ohm stereos input, and then both those channels run in series for the 8ohm input.

So here's my question,

Can I use the Studio Pre in mono (channel A), into the 50/50 (Channel A only), then out of the 50 50 8ohm (Channel A) and into the recto cab's single 8ohm input?

Do I have to use any extra cables aside from the single channel A connectors? Stereo connection are not required with or without use?

It makes perfect sense that for stereo I would use both channel A and B from the pre, and out of both 4ohm A and 4ohm B from the 5050 into the stereo 4ohms on the cab.

Is there any gotchas I'm missing on a total mono set up of both pre and 5050?

Obv I would turn the power on Channel B to zero on the 5050, but do I need to connect a cable?

This mono operation would be just 50 watts going into all 4 speakers of the cab through the single 8ohm correct?


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from the Studio Pre Manual
MAIN OUTPUTS: This pair of 1/4" jacks is intended primarily for connecting the Preamp to apower amp. Its output level is determined by the OUTPUT LEVEL controls on the front panel. Ifyou are using some type of stereo effect in the Preamp’s Effects Loop, then the Main Outs function as a stereo pair. If you’re not using a stereo effect, they function simply as two mono outs (in otherwords, the content of Main Output A will be the same as the content of Main Output B). If you’re operating the Preamp in mono and you are feeding into a mono or single power amp input you can use either Output A or Output B - it makes no difference.

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from the 50 50 Manual

INPUTS

Located on the rear panel, these two 1/4” jacks are the Channel A and Channel B inputs forthe Fifty/Fifty. They are primarily designed to handle the "line-level" signals from a preamp oran effects rack; but they are also sensitive enough to permit direct connection of aninstrument for test purposes, if needed. The amplifier is stereo, offering two separatechannels of amplification. If you wish to use only one of its channels, it is necessary to: 1)Make sure a speaker (or load resistor) remains connected to a speaker jack on bothchannels, including the unused one; or 2) Turn the Level control of the unused channel tozero. (This is necessary because an amplifier channel receiving any amount of signal at itsinput will require a "load" at its output - or else damage will most likely result.)

SPEAKER OUTPUTS
The Fifty/Fifty provides one 8-ohm and two 4-ohm speaker outputs for each channel. Whenusing a single 8-ohm speaker or 8-ohm cabinet on a channel, connect the speaker or cabinetto the 8-ohm jack. If using two 8-ohm speakers (assuming they are wired in parallel) orcabinets on a channel, plug them both into the 4-ohm jacks. (The logic here is that two 8-ohmloads connected in parallel add up to a 4-ohm total load). Mismatching of speakerimpedance will not cause damage or severe loss of power. (Extreme mismatches willdecrease tube life, however).
If you opt to use only one channel of the Fifty/Fifty with speakersconnected to only one channel's output(s), you must turn the unused channel's Level controlto zero! Otherwise the channel will be operating without a load, and damage to the tubesand/or the transformer will result.
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pre and 5050

IMG_3803.JPG


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this is the cab input set up

IMG_3801.JPG
 
I'm guessing this seems like a dumb question. "why wouldn't you just do stereo"

I'll reframe my Q, If I want mono say for an 8ohm 2x12 cab with the stud pre and 5050

- Use only channel A on the pre, into channel A on the 5050,
- turn volume off on channel B on the 5050
- go out of 8ohm channel A on 5050 into 8ohm mono jack in the 2x12

bam, 50 watts into a 2x12 mono... nothing is going to get screwed up?
 
I'm guessing this seems like a dumb question. "why wouldn't you just do stereo"

I'll reframe my Q, If I want mono say for an 8ohm 2x12 cab with the stud pre and 5050

- Use only channel A on the pre, into channel A on the 5050,
- turn volume off on channel B on the 5050
- go out of 8ohm channel A on 5050 into 8ohm mono jack in the 2x12

bam, 50 watts into a 2x12 mono... nothing is going to get screwed up?

The 8 ohm jack on the cab will utilize all four speakers. If you're looking for 50 watts into a 2x12, I would pull the power tubes for the B channel and connect a speaker cable between the one of the A channel 4 ohm jacks, and one of the 4 ohm cab jacks. This has the benefit of saving your unused power tubes some life.
 

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