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Topic: Signal spit after preamp? |
Patrick Fleming
From:
South Dakota, USA
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Posted 4 Aug 2020 5:39 am |
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Hi,
I stole a couple 100 watt power amps from an organ that was heading to the dump and decided to build a couple powered cabs. The first one came out pretty good. Do I need two preamps, or can I split the signal after the preamp to to send to the two power amps?
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Michael Brebes
From:
Northridge CA
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Posted 4 Aug 2020 6:04 am
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You should be able to do a simple split to both amps.
_________________
Michael Brebes
Instrument/amp/ pickup repair
MSA D10 Classic/Rickenbacher B6/
Dickerson MOTS/Dobro D32 Hawaiian/
Goldtone Paul Beard Reso
Mesa Boogie Studio Pre/Hafler 3000
RP1/MPX100 |
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Erv Niehaus
From:
Litchfield, MN, USA
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Posted 4 Aug 2020 6:48 am
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You could always use something like this:
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Jack Stoner
From:
Kansas City, MO
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Posted 4 Aug 2020 8:00 am
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Depending on the preamp and amps you might have ground loop hum problems running both from one split output.
_________________
GFI Ultra Keyless S-10 with pad (Black of course) TB202 amp, Hilton VP, Steelers Choice sidekick seat, SIT Strings
Cakewalk by Bandlab and Studio One V4.6 pro DAWs, MOTU Ultralite MK5 recording interface unit |
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Jim Pitman
From:
Waterbury Ctr. VT 05677 USA
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Posted 4 Aug 2020 12:44 pm
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Nice box!
Great idea too. You could use a stereo affects unit as a pre-amp for some great aural drama. |
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Patrick Fleming
From:
South Dakota, USA
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Posted 4 Aug 2020 4:18 pm
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| Thanks, I am currntly running a joyo american sound into the one and while its not as good as a real twin reverb, I think it sounds pretty pretty good and only 29 lbs. In an ideal world i would run a Sarno V8 octal into them but that defeats the point of building something out of free parts. would a true stereo preamp avoid any ground loop issues? |
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Georg Sørtun
From:
Mandal, Agder, Norway
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Posted 4 Aug 2020 7:38 pm
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| Patrick Fleming wrote: |
| would a true stereo preamp avoid any ground loop issues? |
Most likely not, as regardless of whether the preamp is mono or stereo it will most likely have only one (common) GND.
A simple split, as mentioned/shown in previous responses, will most likely work fine. Only a test will tell if there is a problem with ground loop hum, or not.
The only guaranteed solution against ground loops and resulting hum, is to run the split between the preamp and the two power units via suitable audio transformers with no GND connection through. Which type (coil-ohm) of AT/ATs that will work depends on what load the preamp can drive. |
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