[quote name='Conan' timestamp='1376471556' post='2174259']
I tend to run all basses through their more "appropriate" input channel - actives through the active channel, passives through the passive... and I've never had a problem, even with my 18V Status with full bass and treble boost. But my newest bass (to me, anyway!), the Spector, seems to cause distortion on the active channel
There are a few things that could be causing this I guess, and the easiest fix is the one that I am about to go and do - put a new Duracell into the active preamp! But if that doesn't sort it, could it be that the output of this bass is just too hot for the preamp valve in my LH500? If so, would there be any value in changing it for a valve with more headroom (like the 5751 mentioned above)? Are Spectors known for having a particularly high output?
I'm rehearsing tonight so will get a chance to see if the new battery solves the problem. I hope it does!
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I have an LH500 and a Spector Euro with the adjustable tonepump - I had to use the active input (all my other basses are fine with the passive input even though they have hot outputs) as the Spector was distorting the input quite severely. I changed to an EMG BQS preamp (which has noticeably less output) and now use the passive input on the amp quite happily. Its the mental output of the Tonepump that's causing your issue. You can adjust it down but it seems to take the grit out when you do so.