HK930, Belle Klipsch and Velodyne ULD-15 II

[2ndGenKlipsch]

I recently picked up a Velodyne ULD-15 II for a steal ($250). I purchased this to complement my Belles since I was so spoiled with the massive amounts of bass my Forte II's put out. I'm using the Velodyne with a HK930 and I have a question about how I should hook everything up. The HK930 has preamp outs and power amp ins and the Velodyne servo has preamp ins and power amp outs...piece of cake...hook the in's to the outs. Well I noticed that when the Velodyne servo is turned on the the volume of my mains jumps up significantly so my concern is that the Velodyne servo may be "coloring" the signal some because the Belles sure do sound brighter when the servo is on (it may be my imagination though). My questions are first has anyone experienced any "coloring" when running the signal through a Velodyne ULD Series II servo. Secondly, could I Y the signal coming out the preamp outputs of the HK930 and loop them directly back to the power amp ins, essentially bypassing the Velodyne servo for my mains???

Seth

[dougdrake]

Does the Velo x-over act on signal going into it via the pre-amp inputs? If so, perhaps it's filtering out the bass below the x-over point making the Belles sound livelier since they're not producing the low bass any longer?

Yes, you could "Y" the pre-amp outs of the HK.

[Ki Choi]

It is best to split your preamp out from the HK930 playing the Belle Klipsches at full range and feed your subs with same signal and match the sound pressure level. The crossover built in the ULD-15II is not very good to my ears. The ULD-15II has built in crossover point of 80Hz on DIP resistor chip on later version and DIP chip socket and resistors soldered in for LP and HP points on earlier version. I can help you if you are interested in changing the crossover points on both versions.

On the other hand, judging from my personal experiences with my Belle Klipsches and ULD-15IIs, 80Hz is about right for HP point but Velodyne's built-in crossover has close to 8dB/oct slop for LP and will affect your main Belle Klispches by playing unwanted music information through the sub at lower lever but still hear it if you would get closer.

I have decommissioned my ULD-15IIs for a while but when I used them, I had set their crossover points to 200Hz and used external crossover set at 16dB/oct and 40Hz LP for better performance.

Hope it helps.

Ki

[cwop]

"If so, perhaps it's filtering out the bass below the x-over point making the Belles sound livelier since they're not producing the low bass any longer?"

With the extremely low IM and FM distortion from the bass loading in any bass horn, I cant see the the "clarity" changing at all! I run a Velodyne with my LaScala and if anything they sound more 'lively' without the sub albeit missing the very deepest bass------It could be a level issue when switching components around......If you were running direct radiators for the mains however I would believe you could hear an increase in liveliness with the lesser FMing etc. with the use of the sub........