Convert mono preamp output into stereo (dual mono) output?

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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby Pete B. » Wed Jun 16, 2010 7:42 am

Here is the response I got directly from the RockTron support Tech: Jim Chowning Technical Support 800-388-4447 jim@rocktron.com

Question:
Subject: Velocity 300:
Hi,
Can I use the Velocity 300 to run a mono pre-amp signal to Channel-A only, and plug two 8ohm speakers into the Channel-A outputs in UN-bridged mode (with nothing going to Channel B)?
Then if I need more power, switch to Bridged mode?
Thx,
pete b.

Answer:
Hi Peter;
We do not recommend running the amp at 4 ohms in bridged mode. I would just recommend running each channel separately even if you had to use a Y cord to plug the same mono single output into both amp channel inputs for max power.
Jim

My response:
You can't run two 8ohm speakers in parallel in Bridged mode?!?!?... You're fuckin' fired! :x
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby strumminsix » Wed Jun 16, 2010 8:02 am

Pete B. wrote:My response:
You can't run two 8ohm speakers in parallel in Bridged mode?!?!?... You're fuckin' fired! :x



:lol: :lol: :lol: :lol:
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby tigerstrat » Wed Jun 16, 2010 8:06 am

I am speechless!
"There, in huge black letters, was 'The Grateful Dead'. It just... cancelled my mind out."-Garcia
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby SarnoMusicSolutions » Wed Jun 16, 2010 1:56 pm

I think that's fairly common actually. By bridging the amp and then applying a 4 ohm load to the shared (bridged) amp output, (as I understand it) that's kind of like putting a 2-ohm load on each channel individually, and that's not recommended. Each amp half wants to see a minimum of 4, not 2. So really the way to get full power would be either an 8-ohm load when the amp is mono-bridged, or two separate individual 4 ohm loads per channel with the amp running in "stereo" mode.

When I use my Mc250 amp, I prefer to run the amp as a stereo amp, each half running its own wire to its own JBL. I use a Y-cord to feed both inputs. So the result is mono because it's a mono signal, but the amp is really two mono blocks each with its own speaker running in tandem. That way if one amp section fries, I'm still up and running, maybe a little quieter, but still happening.


B
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby Jon S. » Wed Jun 16, 2010 3:18 pm

Pete B. wrote:Here is the response I got directly from the RockTron support Tech: Jim Chowning Technical Support 800-388-4447 jim@rocktron.com ...

My response:
You can't run two 8ohm speakers in parallel in Bridged mode?!?!?... You're fuckin' fired! :x

I consider myself now at least partially vindicated. :smile:
SarnoMusicSolutions wrote:When I use my Mc250 amp, I prefer to run the amp as a stereo amp, each half running its own wire to its own JBL. I use a Y-cord to feed both inputs. B

Thanks again so much, Brad, for adding the dual mono outs to my preamp so I'll be able to wire my 2X12 similarly and get the same effective results without resort to a Y-chord. :cool:
"For me, I think the only danger is being too much in love with guitar playing. The music is the most important thing, and the guitar is only the instrument." Jerry Garcia
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby strummingturtle » Thu Jan 27, 2011 9:49 am

Jon S. wrote:I don't see the confusion. Per the RV300 manual, In bridged, it's mono in, mono out. In stereo, it's stereo (or dual mono) in, stereo (or dual mono) out. This certainly seems straightforward to me. In any event, it's now a non-issue as Brad will be wiring my unit to have a dual mono out to feed the power amp's stereo (dual mono) in. I.e., I'll be able now to run my unit in stereo - I'm covered! 8)

EDIT: Thought I add, among the reasons I'm into going stereo is I'm going to run each channel, at 75W per side, into it's own individual 8 ohm speaker in a single 2X12 cab. There are benefits to this approach I like.


I have the same set up and was wondering how this is working out for you? right now I am running power amp, bridged (mono) out to one JBL K120 8 ohm.

On another note during practice last night my rocktron cut completely out both channels and seemed to be pretty hot to the touch. After a while heard a click and presto up and running again. Seems to have over heat protection. Any advice to why it is getting so hot? Says it has a fan inside for this purpose. I have never heard a fan running have you?
Rob
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby Pete B. » Thu Jan 27, 2011 11:36 am

Here's how I am currently splitting my mono pre-amp signal to stereo... and beyond...
I got this (for $10 bucks) the same day I got my fist Mutron III pedal, at Seaside Guitars in Seaside, Oregon.
Works perfectly.
My box, instuction card (in japanize on the left, and english on the right), and unit, look identicle to this one I found on the 'net:
Image
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Re: Convert mono preamp output into stereo (dual mono) outpu

Postby hawk900 » Sun Apr 15, 2012 8:05 pm

Weird if it says inoperable by that diag. on the left it looks like one chnl feeds 2 spkrs and the other channel feeds a separate 2 like two amps in one. Even just pop the cover off and hard wire bridge your outputs so it has no choice and just run off one jack McIntosh Jerry style.
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