Anyone use a sub with 2-channel?

steveinaz

Just curious. I've been pondering an SVS 25-31 PC Plus lately, but I want some opinions as far as dedicated music-only systems. I don't want bloat or the home-boy effect in my living room, just something to extend my Athena's down to 20hz....

What do you have? How has it integrated with your main speakers?

dragon1952

I am using an Infinity IL-120 in conjunction with my Paradigm Studio 40's and I'd say it is a definite improvement. These ARE bookshelfs however. I use a crossover of around 60Hz. Not familiar with your speaks though.

gmorris

Of course!

Although my home theater system serves as my 2 channel music system, I certainly do not leave the sub out when listening to 2 channel music.

The only thing I do differently for movies & music is change some setting.

For movies, I set all speakers to SMALL (highpassed) and set the crossover at 80 Hz.

For music, I set the Front L&R as LARGE (full range) and set the crossover at 60 Hz.

The trick to using the sub with 2 channel is to get the sub to blend seamlessly with the Front L&R. I've found the 60 Hz setting makes the sub less locate-able. Getting the volume of the sub at the same level as the Front L&R is also as easy as changing some setting.

If you are lucky enough to have a seperate 2 channel system, integrating a sub will be easy. Get it set up once, and leave it alone.

Turbota

Steve ...

From my signature, you can see that I use an Adire Audio "Rava" sub in my 2 channel only audio system.

You can turn the sub on or off when listening to music. Whether or not you are at low or high listening levels, the sub just makes the music more alive and increases the ambience.

tryrrthg

I'm trying to integrate my new DIY sub. and would like to get it right, I like the added slam and presence the sub adds. I'd like to add some EQ in the future to help flatten out the response.

If you're thinking of an SVS for music alone and don't listen at insane volumes and don't won't bloat, you may want to think of getting the 16-46 or 20-39. You'll get the flattest in room response after room gain with the lower tuned subs.

gmorris

I think no matter what sub you use or how you use it, you will be happy.

The old school philosophy was that a subwoofer could not be integrated into a 2 channel rig because of the blending issue.

With the subs that are available today, this is a non-issue. The adjustments available, such as level, crossover, phase and so on make the blending very easy to accomplish.

tryrrthg mentioned adding an EQ to flatten the response. This is a good idea, but only necessary if you must have that last ounce of perfection. Without an EQ, you can achieve a more than reasonable performace with a proper setup.

organ

I'm using a PSW650 with my Klipsch. No bloating or home-boy effect. As long as you get the crossover point in the right place for a smooth transition from mains to sub, it should improve the overall sound. My crossover is around 50hz.

Maurice

gatemplin

I listen to 2ch with and without a sub depending on which amp I use. When I do use a sub, I use the PEQ to blend with the mains and it is great for Rock, Blues and Classical.
I cant really tell that the sub is on, but I notice a big difference when the sub is off.

organ

Originally posted by gatemplin

I cant really tell that the sub is on, but I notice a big difference when the sub is off.

I hear that's the best way to tell if the sub is properly integrated into the system.

Maurice

steveinaz

Cool, so my Athena's go 35-20kHz +/-3dB, would the "40Hz" crossover point be best in this scenario? The SVS ranges from 40-120Hz on the crossover pot....

organ

Hard to tell. I guess it depends on room acoustics, etc. But I'd start around 60hz and move down slowly from there. My RF-35 drops fast around 37hz and I find that the mid-50 sounds best. You should overlap the cut off point of your mains by 10-20hz.

Maurice

steveinaz

Alright! Thank you Maurice! my house has the "greatroom" concept where the livingroom/dining room are in a single huge space, though my couch sits in an area of about 16' x 20' with a vaulted ceiling that ranges from 8' to 16' at the center. The couch is about 14' from the speakers, speakers about 12' apart.

steveinaz

Originally posted by organ
I hear that's the best way to tell if the sub is properly integrated into the system.

Maurice

That's what I've read as well, makes sense. Thats what I want, just some "support" of the lowest frequencies without any bloating or over-emphasis---tight, distortion-free bass....

VR3

yes...

I cross mine at 60hz, I dont like the way 80hz sounds.

Blends in nicely!

- Sid Da Kid

steveinaz

Thanks for the advice Sponge S...errrr..sorry eh, Sidster.

Dr. Spec

Yes, I use the sub for 2 channel. And I retain an 80 Hz xo.

And yes, it blends beautifully and the combo actually has a flatter FR in the 80-40 Hz region than does the RT800i alone on full range.

I do run a cooler setting for music vice HT, though. Well blending and non-obtrusive bass is critical to me for music. You can't tell where the 800's leave off and the PB2U begins on my system.

gatemplin

Originally posted by Dr. Spec
I do run a cooler setting for music vice HT, though. [/B]

Same here. On 2 ch music the crossover is in the 50's for me and very cool, flat to 16 Hz. On HT though I cross at 100 and crank that sumbitch up.

organ

Sweet. Let us know how it sounds and we want to see pics:).

Maurice

scottdawg

Maybe a dumb question but here it is. How do you hook up a sub to your amp?

gatemplin

You can split the pre amp outputs or use the speaker level inputs on the sub amp to receive a signal.

scottdawg

OK I'll remember that. Thanks

pjdami

I use a Hsu STF-2 in my dedicated two channel rig and like it a lot. Currently, I have two choices of mains here, Polk LSi 9 or Spendor S8s. Both speakers need some help in the lower octave. The trick is calibrating the sub properly in a two channel only system. The way I did it was measure the in room frequency response and plotting it first without the sub (only the mains) and then with the sub. I chose a 50 hz crossover point based on where the mains would start to roll off. I then adjusted the gain on the sub amp plate until I got a relatively flat response. Worked out pretty good for me actually.

I only have one set of preouts on my Musical Fidelity preamp so I experimented here with using the full range Tape Out as a preout and using the crossover switch in the "IN" position on the sub to filter the full range signal at the crossover point at the sub. Turns out the Tape Out has a very high gain so the plate amp gain on my sub is set to like 1 / 5 of what it would normally be with a LFE output. I was kind of worried about doing this, but looks like it works out okay for me.

steveinaz

Originally posted by scottdawg
Maybe a dumb question but here it is. How do you hook up a sub to your amp?

Fortunately, the HCA-1500 has "looping outputs" on the back that allow you to pass on the preamp out signal to other amps--very convenient! Especially since my A3CR only has 1 set of pre-outs...

madmax

I have been considering adding a sub to my 2 channel system. On much material I don't need one but on other material the bass response is not there. My problem is that I'm not sure I should alter the poorer material when I listen to it.
madmax

shack

I use a Dayton 10" Titanic sealed sub with my RT55is. Crossed over at 80 Hz. The 55s do an admirable job by themselves, but the sub adds that extra depth and punch. As others have said...you know it is set up well when you don't know there is a sub until you turn it off.

steveinaz

Max, you wouldn't be altering the music, simply allowing frequencies to be heard that your mains were not capable of reproducing. I think its all in the setup, and of course selecting a good quality sub. The reviews on the SVS have me convinced that they'd be great for 2-channel music if properly set-up, and would extend the lower frequency capabilities of my Athena's. I'm going to make sure that the SVS has a very subtle effect, if I go with it..

Dr. Spec

I'm going to make sure that the SVS has a very subtle effect, if I go with it..

A sub's performance on music is a function of a few things:

1) The spliced in-room frequency response.
2) Distortion levels in the deepest octave.
3) The calibration level.

Sometimes a poor performance from a sub on music is not the sub's fault at all. The room acoustics might suck, and it could just be running too hot.

If you look at my $600 sub shoot-out on HTF, I measured the near-field FR of the two subs. Near field tends to greatly reduce the effect of the room, and shows the true FR of the sub. IIRC, the SVS measured +/- 3 dB from 100 to 20 Hz. It also exhibited very low distortion for its price point. SVS spends a ton of time ground planing subs to obtain a flat FR within the rated bandwidth. Typical ground plane time on the base models is 150 hours, with some of the variable tune/PEQ models taking 3-4X that long. I think it would be safe to conclude if an SVS sounds like hell in your room, it's not the sub.

The ability to measure the spliced (i.e., speakers and sub together) FR in the room at the listening position is extremely important in setting up a sub for 2 channel use.

Aside from basic positioning, the use of a variable phase control can have a huge effect on the FR of the sub. After you tweak the phase control, if the curve still shows some irregularities, a PEQ would be my next step. Some SVS models have a single band PEQ built in. Or you can look at a BFD for cheap.

Ultimately (as Paul quickly found out with his PB1+) great bass is as much set-up and tweaking as it is having a great subwoofer. The best subwoofer out there can sound like hell with the wrong set-up.

Doc

steveinaz

Doc
When you're adjusting the Phase, what are you listening for to get optimum sound integration?

gatemplin

I'm not Doc but I'll tell you what I did anyway,

I made 5 FR graphs using an SPL meter and test tones, changing only the phase in 45 degree increments. I picked the flattest one (happened to be about 180) and then fine tuned with a PEQ. Hope this helps.

Pjdami made a great spreadsheat for use with the Radio Shack SPL meter

steveinaz

Cool. Thanks for the tips.

gmorris

Here is another idea no one seems to have mentioned.

Once you get the sub integrated and setup properly, you can adjust the level of the sub higher or lower. This is NOT like adjusting the tone control, which adds additional bass to the signal. You can simply make the sub louder or quieter.

Traditional audiophiles may scoff at this idea. But who cares. I listen to alot of rock music. I like to turn the sub level up a couple Db's to make bass drum kicks more impactful. If you then switch to acoustic or classical, you can turn the level back to flat to get a more accurate reproduction.

The sub level can help you accomodate your particular tastes. Alot of fun, in my opinion.