Sub connection to CARY SLP-05 preamp

Marty, take a look at the manual for the Velodyne DD subs. Its descriptions of the RTA/EQ processes are similar to what you have described, but I see absolutely nothing in the manual to suggest that those processes would not occur in exactly the same manner if the sub's inputs are at speaker level, driven from the outputs of the main power amp, compared to the configuration in which the sub's line-level inputs are driven from the outputs of the preamplifier.

For the design to be otherwise would make no sense, IMO. At a conceptual level I envision the design as simply dividing down the speaker-level input signals to line-level amplitudes, and then putting them through exactly the same circuitry that is used to process the line-level inputs.

The only difference between the two configurations, I believe, is that if the speaker-level inputs are used, driven by the main power amp, obviously the sub's high pass outputs cannot be connected into the main power amp's inputs. But we are all agreed that using the sub's high pass outputs is undesirable in most cases anyway.

Best regards,
-- Al

If the DD works like my SMS-1 (and I'm told that it's functionally the same), there's a very versatile (fine control of slope, phase, frequency, output level) line level high cut filter to the sub. There's also a crappy, fixed 80hz, 6db/octave low cut to the mains.

The low passed line level signal undergoes ADC, and is reflected on a video screen by the RTA as a sweep tone is generated. The user then applies up to 8 bands of parametric EQ to flatten response and level match the low pass to the main signal (response is displayed up to 200hz). I can assure you guys that this is a very effective way to ensure seamless "hand-off" from main to sub.

OTOH, if you pass at high level, I assume that you keep the crappy 80hz, 6db low cut to the mains, but...

You lose all of that good high cut control for the sub. Basically, you keep the bad and lose the good - I think.

Marty

More good news: The highcut to the mains ain't great sounding either. I use a separate active NHT X2 x-over unit for rolling off the bass to the mains and take the low pass out of the X2 into the SMS for high cutting the sub. The SMS is out of the main path entirely - a good thing IMHO.

Don't know why my post turned up twice. Strange.

You may well be right Al, I was just guessing. The speaker level may go thru the same processing, but intutively, I reached the opposite conclusion....I thought it unlikely that the speaker level signal would see anything but the high pass.

Maybe someone should put the question to Velodyne.

Marty

Edorr,

I tried a Marchand (used) from a local dealer, but the example I got was too noisy to keep. While looking around for a replacement, I tried the NHT on a money back trial basis and ended up keeping it.

Marty

I would second what Almarg thinks in terms of how the velodyne works on both input. It comes in more handy for me to go for connecting the subs from Poweramp since I dont have the XLR splitter while RCA route also uncertain if a good to go. If there is no risk on trying, I will test Almarg way soon. Please confirm. I will also find out if DD-15 (actually its 15") EQ works on speaker input, which I suppose it would to make sense - I mean how would velodyne think people would like to use their sub as a full range speaker on earth....