Hooking up subwoofer in 2CH system..

es347 · « **on:** 2 Mar 2006, 01:47 am »

Hi everyone. I am considering going with a subwoofer in my primary listening system even though many purists will disapprove. With the extended bass now available with SACD I think it's time to really experience it. Before I get into the hookup questions I have, let me tell you what the system consists of:

ARC LS3 preamp
McCormack DNA 0.5
Martin Logan Aerius i (presently bi-wired with MIT Terminator 2 speaker cables)

I am partial to Velodyne subs, specifically the SPL 12 or 15. They recommend hooking their sub into the system by going from the primary line level output on the preamp (L and R) to the sub inputs, then out (L and R) to the power amp. The sub acts as a high pass filter thereby allowing the Logans to only concern themselves with frequencies with which they are comfortable, probably 80 Hz and above?? The other option is to run to the sub from a second line level output on the preamp essentially running the sub in parallel with the Logans which would still attempt to reproduce the entire bandwidth.

You can of course run from the power amp to the sub and then on to the Logans in a satellite configuration but not sure I want to got that route.

Two questions: 1) opinions about this choice of subwoofer, and 2) which is the best option to configure?

Sorry for message length and thanks in advance.

konut · « **Reply #1 on:** 2 Mar 2006, 02:05 am »

You're right, purists prefer the full range add sub where the mains fall off. I disagree. I like to do what you suggest about crossing over at 80hz. That said, most subs use 12db per octave high/low filters which, I feel, are too shallow. I prefer 24db per octave. Its harder to implement cleanly though. Velodyne makes great subs. You can't go wrong with them. My .02 cents, + or - .02 margin of error.

Levi · « **Reply #2 on:** 2 Mar 2006, 02:31 am »

If your subwoofer has a good crossover, I would use the high-level input of sub coming from the amplifier's L-R output. Then use the crossover to adjust how you like the subwoofer to sound with your main speakers.

If you decided to get Velodyne. Velodyne has excellent support group that will walk you through the correct placement and subwoofer crossover settings. They know their sub better than anyone else. The problem with that is your ears. You have to experiment which configuration sounds good to you. A subsystem that's setup properly will actually increase soundstaging and ultimately depth.

You will need a good source with repetitive low bass e.g. Rob Wasserman to setup your subwoofer crossover and placement.

I personally like to use REL subsystem. It has excellent crossover that allows you to use both high-level input and low-level input if you have 2ch and 5.1ch system. But that's another topic.

budyog · « **Reply #3 on:** 2 Mar 2006, 03:59 am »

I consider myself an audio purists and I believe in a subwoofer and after the 2 Velodynes I have owned, I couldn't be happier with the ACI "Maestro". Far superior to the Velodynes all around.

warnerwh · « **Reply #4 on:** 2 Mar 2006, 08:22 am »

I'd consider other subs besides Velodyne. I think they are overpriced and aren't as great as they're built up to be. You're also paying alot for advertising dollars. There's no doubt in my mind that the speaker makers on this forum can do better per dollar.

I like running my main full range speakers full range and just augmenting with a sub. I cross my sub at about 45hz which is just right with my speakers which are Vmps RM 40's. With your setup it's a tough call as you have a low powered amp and a higher crossover to the satellites will probably be the way to go.

Please check with our local makers here. These guys all have excellent customer support and offer very high value. You can probably get the same performance for half the price.

woodsyi · « **Reply #5 on:** 2 Mar 2006, 01:49 pm »

Quote from: es347

Hi everyone. I am considering going with a subwoofer in my primary listening system even though many purists will disapprove. With the extended bass now available with SACD I think it's time to really experience it. Before I get into the hookup questions I have, let me tell you what the system consists of:

ARC LS3 preamp
McCormack DNA 0.5
Martin Logan Aerius i (presently bi-wired with MIT Terminator 2 speaker cables)

I am partial to Velodyne subs, specifically the SPL 12 or 15. They recommend ho ...

The woofers on your hybrid is 3db down at 40Hz according to ML site. If you add your sub and run your Aerius full, I would think you need to bring your sub in at a lower point than 80 Hz. If the sub(s) are good, maybe you can just run the ESL panels and leave the woofers out? I have subs coming in at 70Hz with my Soundlabs (actively crossed).

fredgarvin · « **Reply #6 on:** 2 Mar 2006, 02:41 pm »

I auditioned the Aerius some years ago and found that crossing the sub at 80hz produced bass that was much slower than desired. The salesman than crossed it over at a lower point (dont remember where) perhaps at 50 or so and the bass was better, more integrated. I agree that the Aerius really needs a sub to sound its best.

Folsom · « **Reply #7 on:** 2 Mar 2006, 03:28 pm »

I would use a power crossover to seperate the low and the high. I am actually building a pre-amp with this in it!

24db is much better, I would cut your speakers off at 45hz because the roll off will be very good if the -3db is at 40hz. With a powered crossover you can set the crossover on the subwoofer a bit higher than the power crossover, so it will have a more constant SPL curve, better flat line frequency response until cutoff.

That is what I would do.

What subwoofer would I choose? Well unless you use this setup for HT I would not be interested in the biggest power house subwoofer I could get my hands on, UNLESS I liked pipe organs A LOT. I would be looking for some thing that extends to 20hz at no lower than -3db just to fill in the complete range, with not too big of Xmax, I would want some speed.

Doug_B · « **Reply #8 on:** 2 Mar 2006, 04:26 pm »

Quote from: Destroyer of Smiles.

I would use a power crossover to seperate the low and the high. I am actually building a pre-amp with this in it!

Any recommendations for a power crossover (although you're planning on pre-amp integration)?

Also, is it not of value to use a parametric equalizer or similar for the signal going to the sub, assuming no equivalent functionality is integrated in the sub proper?

Thanks.

Doug

Folsom · « **Reply #9 on:** 2 Mar 2006, 06:25 pm »

Quote from: Doug_B

Quote from: Destroyer of Smiles.
I would use a power crossover to seperate the low and the high. I am actually building a pre-amp with this in it!

Any recommendations for a power crossover (although you're planning on pre-amp integration)?

Also, is it not of value to use a parametric equalizer or similar for the signal going to the sub, assuming no equivalent functionality is integrated in the sub proper?

Thanks.

Doug

Well I am using XM1 PCB's and a few changed parts fom Marchand. They do sell this

http://www.marchandelec.com/xm9.html

It looks like a nice crossover to me.

As far as an equalizer for a subwoofer I suppose it would be pretty dependent on your subwoofers response. If you have a very flat response in your desired range, say with a ported box, I doubt the need for one with a crossover like the XM9. Also though you might have to account for room gain, however that might as easy as adjusting the gain level, and not independent areas of the playing frequencies.

If you had a sealed box you might find the response to not be as flat so an equalizer would be useful. At least I find more then a handful do not have really flat response curves.

I have no idea about your room, and the subwoofer is undecided. I am just going to stick with electronic crossover recommendation first. Excuse my cynicism of a plate amplifiers ability to be a really good crossover, I just do not see it.

es347 · « **Reply #10 on:** 2 Mar 2006, 08:05 pm »

es347 · « **Reply #11 on:** 2 Mar 2006, 08:09 pm »

<<Please check with our local makers here. These guys all have excellent customer support and offer very high value. You can probably get the same performance for half the price.>>

How can I contact these folks? Do they have URLs posted here anywhere??

Thanks to all who responded. I have lots to consider now.

Gavin Hadley

konut · « **Reply #12 on:** 2 Mar 2006, 10:37 pm »

I'm glad DOS mentioned Marchand. I just ordered 2-XM46 modules. These are passive line level filters. I ordered 24db per octave high pass filters at 70hz. I am going to use these with one of the products a Circle manufacturer makes. If you click on the Circles link on the top right of the page you get a page with all the manufacturers represented here with the URLs. Click the AV123 URL. Go to their products tab. Click subwoofers and find the UFW-12. Thats what I own. The UFW-12 comes with a 5 band digital parametric equalizer, called RDES, but it hasn't shipped yet. With this you can customize a low pass filter in any number of ways to 'feather' it into the response of your main speakers. BTW, the UFW-12 is the tightest, cleanest, and fastest sub I've ever heard. I'll use a Y cord to split the signal after my passive preamp. 1 split will got to the XM46 and then to my amp and main speakers, and the other split will go to RDES and then the sub.

Jason1 · « **Reply #13 on:** 3 Mar 2006, 12:42 am »

Another option is the HSU powered crossover.

http://www.hsustore.com/highendcrossover.html

Folsom · « **Reply #14 on:** 3 Mar 2006, 04:14 am »

Quote from: konut

I'm glad DOS mentioned Marchand. I just ordered 2-XM46 modules. These are passive line level filters. I ordered 24db per octave high pass filters at 70hz. I am going to use these with one of the products a Circle manufacturer makes. If you click on the Circles link on the top right of the page you get a page with all the manufacturers represented here with the URLs. Click the AV123 URL. Go to their products tab. Click subwoofers and find the UFW-12. Thats what I own. The UFW-12 comes with a 5 band digital ...

What driver does it use?

konut · « **Reply #15 on:** 3 Mar 2006, 04:37 am »

I'm not sure. I know that its made in the USA because just before it was released the chinese made driver was pulled because of inadequate performance. A driver that was being designed for a higher priced design was substituted. You might want to post that question on the AV123 circle as, at the time, someone correctly deduced the manufacturer on the AV123 forum, but I just don't recall.

Doug_B · « **Reply #16 on:** 3 Mar 2006, 08:56 am »

Quote from: Destroyer of Smiles.

Well I am using XM1 PCB's and a few changed parts fom Marchand. They do sell this

http://www.marchandelec.com/xm9.html

It looks like a nice crossover to me.

As far as an equalizer for a subwoofer I suppose it would be pretty dependent on your subwoofers response. If you have a very flat response in your desired range, say with a ported box, I doubt the need for one with a crossover like the XM9. Also though you might have to account for room gain, however that might as easy as adjusting the gain level, and not independent areas of the playing frequencies.

Thanks for the link. Reason why I ask is that I have a crossover now that I originally put in for multichannel audio purposes that I use in the system to support 2 channel as well, the Outlaw ICBM. I figured that the ICBM might not be up to snuff for "discriminating" 2 channel audio. BTW, I also use an equalizer (BFD) for the sub out from the ICBM.

Since that time, I have added a pre-amp so that my 2ch audio bypasses the HT controller. Although my pre-amp has two sets of outputs, I've been too lazy to reconfigure so that my mains get a direct feed from the pre-amp - I'd have to redo the BFD settings

. That said, I still like the idea of not sending a full range signal to my mains (8" woofer).

Doug

woodsyi · « **Reply #17 on:** 3 Mar 2006, 01:05 pm »

Quote

That said, I still like the idea of not sending a full range signal to my mains (8" woofer).

I have two 10" drivers on my mains that I band pass to do just 80 to 280. I let the subs with 2 15" and 2 12" drivers to shake the house below that. If you can integrate seamlessly, you get a much clearer and articulate midbass out of your mains this way. I also don't "contaminate" the ribbons (stats in your case) with x-over circuitry by relying on built in passive filter. Good luck. You got a lot of fiddling to do. But it's worth the effort. I found the test tones from Real Trap (10Hz throuh 300 Hz by each frequency) invaluable in bass management. You can use a measuring mike and software for analyses or use just a Radio Shack sound meter.

crossroadazn · « **Reply #18 on:** 3 Mar 2006, 01:52 pm »

I'm second to REL sub because your Martin Logan are fast response speakers so the REL will match up nicely.

Doug_B · « **Reply #19 on:** 3 Mar 2006, 03:48 pm »

Quote from: woodsyi

I have two 10" drivers on my mains that I band pass to do just 80 to 280. I let the subs with 2 15" and 2 12" drivers to shake the house below that. If you can integrate seamlessly, you get a much clearer and articulate midbass out of your mains this way. I also don't "contaminate" the ribbons (stats in your case) with x-over circuitry by relying on built in passive filter. Good luck. You got a lot of fiddling to do. But it's worth the effort. I found the test tones from Real Trap (10Hz throuh 300 Hz ...

If I understand you correctly, you're recommending feeding each driver in the mains separately and using external (active?) crossovers to keep "contamination" of frequencies to each driver at a minimum (BTW, I have ribbons as well with segregated binding post inputs, so this is possible). It also sounds like you're recommending an equalization step, otherwise SPL measurements from a Radio Shack meter, for example, would be informational only, unless the result was a smooth response without it.

Thanks.

Doug