Just received my Sadowsky bass preamp.

[ShowKing]

I plugged it into my lakland 55-02 with the lakland preamp in bypass.
then i switched on my sadowsky preamp and there is a loud hum, and i cant do anything else with it.

anyone have this problem?
what should i do?

[ShowKing]

i just tried using it without the AC adaptor and the hum's gone.
but still the preamp made no difference to my tone/volume even when i switched it on and off.

[LightGroove]

Just so I'm clear...your running an active bass into an active outboard preamp?

I understand you had it in passive mode but I think there still may be conflicts.

[basadam]

Originally Posted by sungjin891118

i just tried using it without the AC adaptor and the hum's gone.

I know for a fact that Sadowsky DI does not like some AC adapters. If your country is 110v get Sadowsky adapter, if 220v I use one from Ibanez and it works fine (there is an oh-so-slight hiss when engaged).

but still the preamp made no difference to my tone/volume even when i switched it on and off.

Did you play with bass/treble controls. Especially with bass you should hear a huge difference. When everything is flat (vol@max, bass&treble@min) Sadowsky pre is close to transparent.

[vin*tone]

Your AC adaptor is probably not filtered. You can get lucky with other adaptors but its safer to get one specially made for audio. I've never tried a switchmode one (SMPS) but they're supposed to be pretty quiet (Like OneSpot)

[LightGroove]

WOW..interesting to hear the Ac adapters cause that much of a fuss...learn something new every day

[ShowKing]

Originally Posted by LightGroove

WOW..interesting to hear the Ac adapters cause that much of a fuss...learn something new every day

just got an email from Roger saying ONLY the regulated FISHMAN Adaptor will work with the sadowsky

[slaerts]

I used a 9v battery in mine, they are quite economical on batteries. There should be a noticable change in tone too.

Originally Posted by LightGroove

Just so I'm clear...your running an active bass into an active outboard preamp?

I understand you had it in passive mode but I think there still may be conflicts.

No, you can run it with an active bass with no problems, it does not exist entirely for passive basses I used a bass which had an OBP-3 on it because I liked what the sad did to the tone. The only problem would be if there was something wrong with his passive mode - do you have another bass to check it with?

[Steve Bennett]

Originally Posted by sungjin891118

i just tried using it without the AC adaptor and the hum's gone.
but still the preamp made no difference to my tone/volume even when i switched it on and off.

Did you have the bass and/or treble controls up at all? If not, you'll get the same unaltered signal as when the unit's off.

[Steve Bennett]

I tried a few different AC adapters with mine, including a regulated Boss unit, and they all hummed to some degree. I contacted Roger and he said to buy the Fishman from Sadowsky, and if I get any hum he'd take care of it. I just decided to use a battery with it for now. It gets good mileage out of a battery as long as you remember to unplug from the input when not using it.

[pmcd]

I regularly power my Sad DI with a 1 Spot power supply with no issues whatsoever.

[OshKoshJoash]

thats strange because with my one spot, there is definitely a hum.