SMS-1 for dual purposes

Posted by: ted_b

SMS-1 for dual purposes - 03/15/08 06:34 PM

I've been happy with my SMS-1 for almost two years now. I first sued it to augment the anemic lf of my former main stereo speakers (running mains full range and dialing in Paradigm Servo 15). I now have full-range SP Tech revelations that really don't require a sub at all, so I use the SMS-1 to EQ my movie and mirez multichannel from the processor.

However, a buddy of mine asked this question and i began to think about it. Could 1 SMS-1 handle both the above scenarios? If you had a stereo pre that had dual main outs, and ran one set (call it rca) to the SMS-1, and also had a movie processor that had an XLR LFE out, and also ran IT to the SMS-1, and had an SVS PB13-ULtra that has both inputs (rca and balanced) could you set up the SMS-1 with different presets to handle both jobs. Preset 5, for example, would have a certain mual EQ dialed in at say 57hz, and be properly EQ'd for the main speakers; then have Preset 6, for example, set for no corssover (xover being set in processor), and EQ'd for LFE sounds? When just listenbing to stereo, select preset 5, yada yada....?? Anybody?
Ted
Posted by: gonk

Re: SMS-1 for dual purposes - 03/15/08 09:20 PM

In concept, this will work. A few things come to mind, though. First, the unbalanced and balanced inputs and outputs are not independent (a balanced input is available at the unbalanced output and vice-versa), so you'd only need one connection so the sub and you'd only want one system on at a time. Second (and this is a rather frivolous comment), remember that preset 6 is the bypass mode - you'll not be able to use it for this.
Posted by: Dan Marchewka

Re: SMS-1 for dual purposes - 04/08/08 06:39 PM

Thanks for the response gonk. I was just getting ready to ask a question about the balanced and unbalanced connections! I wanted to use the unbalanced RCA inputs for my 2-channel pre and the balanced XLR input (with adapter) for my 970, and use the one of the LFE outputs to go to my sub. Obviously, I know I would have to turn off on of the sources, or I would get both of them mixed in the sub. But, I wasn't sure if the RCA ins/outs and XLR ins/out were independent of each other. According to you, the inputs and outputs (both sets) are all tied together. So, you can mix and match!

Thanks again,
Dan
Posted by: Bill Mac

Re: SMS-1 for dual purposes - 02/26/09 03:42 PM

I have a similar setup question as ted b. I am trying to use my LFM-1 with my Bel Canto PRe3 as well as with my Onkyo 805. It has been suggested that the SMS-1 would be a good choice.

The one problem I see is that the PRe3 when in HT Bypass mode has to be powered on for use when using my system in HT mode with the 805. Now I have the R&L preouts of the 805 connected to the #5 input of the PRe3 (the HT Bypass input) then the R&L preouts of the PRe3 to my amp. I see in gonk's earlier post that one of the pre amp or processor has to be powered off.

In order to connect the PRe3 to the SMS-1 I would use the XLR output of the PRe3 to the XLR input of the SMS-1. Then I would connect the LFE output (RCA) from the 805 to the LFE (RCA) input of the SMS-1.

The issue I see is that when in HT mode feeding the SMS-1 a signal from my 805 (LFE output) and also from the PRe3 that the SMS-1 will be seeing R&L signal from the 805 through the PRe3. The reason I think it will be a problem is that both the PRe3 outputs are active at the same time.

Now would this work if just used the R&L output of the PRe3 to the SMS-1 and then feed my amp through the SMS-1 and eliminate the LFE output from the 805? This way using the SMS-1 to set all x-over and sub level settings?

My apologies for the confusing post but I am trying to use a sub when listening to 2CH music with my PRe3. When using my system in 2CH mode the 805 is powered of if that matters.

Thanks in advance for any help with this.

Bill
Posted by: gonk

Re: SMS-1 for dual purposes - 02/26/09 07:01 PM

This is a tricky one, and I am not entirely sure that I've got it worked out - but I've got a thought or two percolating that might be useful. First, a question. Does the PRe3 have internal bass management such that you get a subwoofer signal from it?
Posted by: KOYAAN

Re: SMS-1 for dual purposes - 02/26/09 09:42 PM

Doesn't that setup get a little tricky for controling volume for multi-channel sources ?
Just a suggestion, but you might want to run you pre-out from the PRe3 to the Front left and right 7.1 inputs of the 850, assuming that these aren't already used for SACD/DVD-A. Then leave the Bel Canto at a fixed volume and drive all speakers and the SMS-1 with the Onkyo 850.That way all volumes would remain consistant amoungst the speakers and the 850 could handel the base management. I wouldn't think that passing through what is essentially a pre in on the 850 would degrade the SQL of the Bel Canto.
Posted by: Bill Mac

Re: SMS-1 for dual purposes - 02/27/09 01:09 AM

Quote:
Originally posted by gonk:
This is a tricky one, and I am not entirely sure that I've got it worked out - but I've got a thought or two percolating that might be useful. First, a question. Does the PRe3 have internal bass management such that you get a subwoofer signal from it?
gonk,

The PRe3 does not have any bass mangement capabilities. I wish it did as I could just use a Y adapter to the sub cable from the 805. Thanks for your help!

Bill
Posted by: Bill Mac

Re: SMS-1 for dual purposes - 02/27/09 01:11 AM

Quote:
Originally posted by KOYAAN:
Doesn't that setup get a little tricky for controling volume for multi-channel sources ?
Just a suggestion, but you might want to run you pre-out from the PRe3 to the Front left and right 7.1 inputs of the 850, assuming that these aren't already used for SACD/DVD-A. Then leave the Bel Canto at a fixed volume and drive all speakers and the SMS-1 with the Onkyo 850.That way all volumes would remain consistant amoungst the speakers and the 850 could handel the base management. I wouldn't think that passing through what is essentially a pre in on the 850 would degrade the SQL of the Bel Canto.
I really do not want to run the signal from the PRe3 through the 805. It would kind of defeat the purpose of the dedicated 2CH preamp and effect SQ. For 2CH music listening the SQ of PRe3 is much better than the 805 by far. Thanks for your suggestion though.

Bill
Posted by: gonk

Re: SMS-1 for dual purposes - 02/27/09 02:01 AM

Quote:
Doesn't that setup get a little tricky for controling volume for multi-channel sources ?
It sounds like the PRe3 has a home theater bypass, which makes volume control straightforward: the PRe3 basically becomes a straight wire for the 805's pre-amp outputs.
Quote:
The PRe3 does not have any bass mangement capabilities. I wish it did as I could just use a Y adapter to the sub cable from the 805. Thanks for your help!
Let me toss out a crazy idea, then. Set the front speakers to large and disable the subwoofer output on the 805, then route the left and right channel pre-amp outputs from the 805 to the PRe3 (as you already are) and the left and right channel pre-amp outputs from the PRe3 through the SMS-1 on their way to the power amps. Then connect the subwoofer to the SMS-1. You are basically going to use the SMS-1's built-in 80Hz analog high-pass crossovers for the left and right channels, so you'd want to set the digital low-pass crossover in the SMS-1 to 80Hz to match up with it. The 805 would mix the LFE channel into the left and right channels, where it would end up getting split back out by the SMS-1. Whaddaya think?
Posted by: Bill Mac

Re: SMS-1 for dual purposes - 02/27/09 02:52 AM

Quote:

Quote:
The PRe3 does not have any bass mangement capabilities. I wish it did as I could just use a Y adapter to the sub cable from the 805. Thanks for your help!
Let me toss out a crazy idea, then. Set the front speakers to large and disable the subwoofer output on the 805, then route the left and right channel pre-amp outputs from the 805 to the PRe3 (as you already are) and the left and right channel pre-amp outputs from the PRe3 through the SMS-1 on their way to the power amps. Then connect the subwoofer to the SMS-1. You are basically going to use the SMS-1's built-in 80Hz analog high-pass crossovers for the left and right channels, so you'd want to set the digital low-pass crossover in the SMS-1 to 80Hz to match up with it. The 805 would mix the LFE channel into the left and right channels, where it would end up getting split back out by the SMS-1. Whaddaya think? [/QB]
gonk,

That was my idea as well! So seeing that you have also suggested it means it will work quite well! Yes the PRe3 does have HT Bypass, it is a great option to have.

Another question. With the setup as you suggested is there a way to disable the sub for 2CH if I just wanted to listen in full range for my R&L front speakers? Basically a way to defeat the SMS-1 and send a full range signal to my amp from the PRe3 (805 off). Also do you think that the SMS-1 will degrade the SQ of the PRe3? Or will it pass the signal untouched? Thanks again for your help I really appreciate it!
Posted by: gonk

Re: SMS-1 for dual purposes - 02/27/09 04:46 AM

There is no way to disable the 80Hz high-pass on the left and right channels of the SMS-1. You could probably set up one of the SMS-1's presets to disable the subwoofer (set its volume to zero, for example), but you'll lose that sub-80Hz information for your mains.

Since the SMS-1 leaves the left and right channels in the analog domain, I wouldn't expect it to be a problem for audio quality, but I've never tried it (my SMS-1 just gets a subwoofer signal).