[drake]

Hello guys I am hoping someone here can give me some feedback. I am gathering the equipment for an HT / Sound room and I need a subwoofer. Doing my research I came up with three options but if there are other please let me know : )

TC Sounds LMS-4000 with TC Sounds passive radiators and a big amp “Behringer Ep2500 or Carvin HD1800”

Rythmik audio Servro sub with matching amp “which is a TC Sounds woofer”

Gr-Research subwoofer and matching passive radiator “looks like a peerless sub” and a Apex "Senior" Subwoofer Amp with remote control

The TC Sounds LMS-4000 reminds me of the Eclipse Audio subs “which were made by TC Sounds” that I used to install back in my car audio days. Is the price of the LMS-4000 and a large amp really worth the added 3db or so?

Does anyone have any experience with the Gr-Research sub?

Problem is I really like the high XMAX woofers and I am not sure the GR or the Rythmic will move as much air as I would like. I would like 110db or more out of one sub at 20hz. I guess I could use two GR subs?????????????? But the wife might think I am nuts.  aa

My mains “ I THINK, still trying to decide” will be a mini line array with 4 GR Research M-165X midbass and a planar tweeter per cabinet with an active crossover and bi-amped with a Tripath class G diy kit amp. I have built many speakers and used to work as an installer in car audio for years but my experience is in largely in car audio, which is why I need some help.  Although I did make a killer pair of Transmission Lines about 7 years ago. 

[Daygloworange]

I've had the GR PR sub with Apex Sr plate amp for a while now. With the resistor mod, the amp extends down to a corner frequency of 12 hz. I have mine crossed over at 40 hz. The plate amp is fed a signal from my pre-amp. The volume on the plate amp is just a tick over 9 o'clock ( 25 %) when run with my AV/ 3's or OB 5's, which are 90 and 91 db efficient.

I'd probably say to go with 2 subs rather than 1 with lot of Xmax. More drivers equals less effort, equals less distortion. If you are going to run this on a main floor, at any kind of spirited level, much less 110db, everyone will be pissed, including the people down the street.

Here's an idea what you can expect:

http://www.audiocircle.com/index.php?topic=34105.50

Cheers

[drake]

Thanks Daygloworange! That was exactly the kind of info I was looking for.

[Daygloworange]

No prob.



I'm going to build a new sub with this driver/amp combo. The box will be made from thicker MDF, It will have lead/sand filled chambers, the bracing inside will be done differently, No Rez for damping inside, I will also downfire the Active woofer. Should kick up the performance even more. 
 
Cheers

[drake]

Keep me posted on your sub project!!! If it works I might have to build one. 
I like your A/V-3's very nice. Are they the TL version??

I cannot decide if I want to use the new GR Research M-165X drivers or wait on the line source drivers from TC Sounds.http://www.tcsounds.com/linesource.htm#overview

The VMPS RM40 and other designs that use the planar drivers are making it a difiicult decision.

Matt

[Daygloworange]

drake,

Yes, the AV/3's are a transmission line. I will update on the sub project. I have been talking to a couple of people who have done a lot of experiments with downfiring subs, so I want to make sure I get the proper distance off the floor.

If you're looking for line arrays, look at the LS 6 and LS 9 Danny designed for AV123.

http://www.audiocircle.com/index.php?topic=34105.0

Cheers

[drake]

What is the benefit of downfiring the sub??

[Daygloworange]

In the case of the PR sub, you have the active driver, and the passive radiator, and the plate amp all mounted on the sides of the box. I'd like a driver facing forward for aesthetic reasons primarily, but that would mean if the plate amp is on the back, then the other driver would be on the side. Again, aesthetically, not desirable. But if I can have one underneath, then I achieve my goals aesthetically.

So, I will down fire the active woofer, and have the PR facing forward. You can't do it with the PR radiator facing downward, because of the effect of gravity on the motorless driver.

The other benefit will be that because the drivers are so close to the floor, and there are no grills to protect them, they could accidentally get damaged. The downward facing one is now out of harm's way. The PR radiator face is much more durable than the paper of the active woofer.

Sonically, I don't really think there is any benefit to speak of. Not that I'm aware of. I'm chatting with some people who have experimented quite a bit with sub woofers, and I want to make sure I don't do anything that would have an adverse effect on the sound.

Those are the reasons why I've chosen to downfire it.

Cheers

[mpauly]

Dayglow.....I'd be real interested in how you handle the internal bracing with the active/passive radiator being on 90 degree axis to one another.  Keep us posted.

Michael

[Daygloworange]

Dayglow.....I'd be real interested in how you handle the internal bracing with the active/passive radiator being on 90 degree axis to one another.  Keep us posted.

Michael

To accommodate the notch you need for the basket of the PR the braces will have to be notched, I've kind of got an idea how I'm going to do it, but when I come up with a final design aesthetic for the enclosure and start building it, then I'll decide. Sometimes I work out at the details in advance, sometimes I do it during the process. This time it's during the process.

I'll post pics when I start doing it.

Cheers

[drake]

I took the plunge and ordered the woofer and passive radiator from GR-Research. Now for the amp, is the apex senior http://www.apexjr.com/Apexsenior.htm a good amp or is there a better option. The wife and I like the idea of the remote control. Any advice would be greatly appreciated. : )

Matt

[Daygloworange]

drake,

That's the amp I'm using with my PR sub. It more than powerful enough in my system. It runs at just a tick over 25% of full volume, has a fully adjustable phase 0- 180 deg. and adjustable crossover frequency. I don't have the one with the remote, as I don't need that in my system, but it's available with one.

I'm very happy with the set up.

Cheers

[drake]

Thanks!!! I really appreciate the help!!!!!!!!!!!!!

Matt