[ec]

Anybody here using the Velodyne SMS-1 with their SP 1.7? 

Setup:

SP 1.7 sub out unbalanced feeds two Buttkicker Amplifiers
SP 1.7 sub out balanced feeds Symetrix 551E Parametric EQ which then feeds two Crown K1' s (hey cut me some slack all my other amps are SSTs  )

I replaced the Symetrix PEQ with a Velodyne SMS-1 and did a quickie auto calibrate.  Now when I turn on my SP 1.7 (which triggers on the Crowns via a switched power station) I get a slight thump in the subs.  I also noticed a pronounced thump in the subs when I switch from DVD to Satellite.  Similarly there is a cha-chunk on the Buttkickers SP 1.7 power on turn on and source switch.  These problems did not exist previously with the Sysmetrix 551E.  What seems stranger is that the SMS-1 (balanced connection) seems to affect the unbalanced connection on the SP 1.7

The Velodyne SMS-1 is always left on just like the Symetrix it replaced.  I will call Velodyne when I get a chance but I thought I would throw this out to the crowd in case they have the SMS-1.

Thanks

[ec]

After a few hours of trying to identify the problem, I found the root cause - strangely the problem only occurs with one specific Buttkicker amp (I run two BK amps) and the SMS-1.  I replaced the Buttkicker amp to minimize the thumping problem.

[mlawson66]

I also noticed a pronounced thump in the subs when I switch from DVD to Satellite. 

Do you still have the thump when you change from DVD to Satellite? I've got a similar problem with my SP2. Whenever the digital signal changes format, ie PCM to 5.1, I get a thump out of all speakers. It is enough to blow fuses in my Ampzilla 2000 monoblocks. I manually mute before changing channels or sources now.

All of my amps will do XLR, but I have a 7.1 system, and the SP2 only has balanced outputs for 5.1.

[thxultra]

My DD sub thumps when using xlr connection but not with rca , the sms1 also does this when connected this way.

Not sure whether its just a velodyne thing or it happens with other manufacturers

Its just something that happens 

[ec]

Do you still have the thump when you change from DVD to Satellite? I've got a similar problem with my SP2. Whenever the digital signal changes format, ie PCM to 5.1, I get a thump out of all speakers. It is enough to blow fuses in my Ampzilla 2000 monoblocks. I manually mute before changing channels or sources now.

All of my amps will do XLR, but I have a 7.1 system, and the SP2 only has balanced outputs for 5.1.

Yes, I still get the thump when switching sources but it is greatly reduced from when I first posted.  I also get the thumps when the SP 1.7 is switching between modes or finding modes eg the "space" between the trailers on DVDs.