I bought a broken SWR Mo'bass off eBay - the obvious fault is that
one of the two PA modules is missing.
Is there a way of aquiring a new one, without spending too much?
Or perhaps get a matching aluminum cooling tube, and replicate
the circuitry (OK, quite a lot of work)?
Otherwise, since I won't be needing that much power (I'm currently
happy with a 350 W SWR red face head), I'm guessing that I might
just set the amp up to run with one PA module?
Another thing I was thinking of doing to this amp, is to replace the
power transformer (mainly because in Sweden we have 240 V in the
outlet). Does anyone know the VA rating for the stock Mo'bass
transformer? The SWR recommendation for a 240/120 V transformer
with this amp is 1200 VA, to match the (claimed) power output of
2x400 W or 900 W bridged.
Now, the stock transformer (EI type) looks kind of small for a 1200 VA.
Two toroidal off the shelf 500 VA transformers would fit in its place,
with the added benefit of added isolation between channels (would
anyone hear it - no), and less hum (OK we have plenty of that from
the guitarists Marshall amps).
But then again, if the stock transformer is, say, 800 VA, then I guess
adding more power to the transformer might increase the risk of
the PA stage to burn (since the design *might* have been done
with transformer saturation limiting the power).
Any creative input to this would be helpful, thank you!
one of the two PA modules is missing.
Is there a way of aquiring a new one, without spending too much?
Or perhaps get a matching aluminum cooling tube, and replicate
the circuitry (OK, quite a lot of work)?
Otherwise, since I won't be needing that much power (I'm currently
happy with a 350 W SWR red face head), I'm guessing that I might
just set the amp up to run with one PA module?
Another thing I was thinking of doing to this amp, is to replace the
power transformer (mainly because in Sweden we have 240 V in the
outlet). Does anyone know the VA rating for the stock Mo'bass
transformer? The SWR recommendation for a 240/120 V transformer
with this amp is 1200 VA, to match the (claimed) power output of
2x400 W or 900 W bridged.
Now, the stock transformer (EI type) looks kind of small for a 1200 VA.
Two toroidal off the shelf 500 VA transformers would fit in its place,
with the added benefit of added isolation between channels (would
anyone hear it - no), and less hum (OK we have plenty of that from
the guitarists Marshall amps).
But then again, if the stock transformer is, say, 800 VA, then I guess
adding more power to the transformer might increase the risk of
the PA stage to burn (since the design *might* have been done
with transformer saturation limiting the power).
Any creative input to this would be helpful, thank you!
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