Loud hum on start-up.

[rczinger]

When we first turn on the SV1 it's got a really loud hum. We shut it off and back on...it's better. Sometimes we have to do this several times.

The XLR outputs are unusable with a loud hum as well. We have to use a direct box and the 1/4 output.

We run the SV1 headphone jack to our Jamhub headphone monitor. If that cord isn't plugged in we get a hum in the mains from the SV1.

Hooked to a Behringer X32 digital mixer at our church.

My daughter has a Korg SP250 that has none of these problems.

I've seen other posts with noise issues but no resolution is posted. What's up with that?

[rczinger]

No one's got anything on this?

Another issue is that we have to use a direct box to have the SV-1 noise free. If we use the XLR's or 1/4" it has a hum.

So far we're pretty disappointed with the SV-1. The SP-250 is problem free.

[javaj]

Was it new? Standard response- send it back to get fixed. It's not like it is just a small circut inside- it has some guts to it, and a tube.
Also, have you replicated the hum when the power is plugged to a different outlet (in case you have something wrong with the church's power line).
I can attest that this is a huge issue nowadays (and with older churches even more- they weren't designed to have all the new high powered gear and electronics running on their wiring).

Hum can also be a sign of some bad grounding- by chance, do you get any tingling sensation if you touch the SV-1 with your wrist (try the power switch).

I get a clicking at home and I know it is because of all the stuff I have plugged in to the same circut.

[aliduri]

At least they should be marked as uncertain and removed if no further signal is received within 24h or so..

Hum TV

[oy5t3h]

No one's got anything on this?

Another issue is that we have to use a direct box to have the SV-1 noise free. If we use the XLR's or 1/4" it has a hum.

So far we're pretty disappointed with the SV-1. The SP-250 is problem free.

Gotta be a mains ground loop. The SP-250 uses an external DC power supply, so it's isolated from the Mains Earth voltage. Either
a) plug all your instruments into the same mains supply socket, or
b) isolate the signal ground with a DI box or Isolating transformer, or
c) use an instrument with an external DC power supply, like the SP-250.

Or remove the earth connection from the mains plug on the the SV-1 power lead. Note, however, that this last piece of advice is decidedly unsafe, and if you electrocute yourself after taking it, then it's your own fault - not mine!.