Which Audio (hifi) Sub kit do you recommend?

[rythmikaudio]

Originally posted by AJinFLA
Hi Mac,

yes, the W-frames as well as the Thors are very good subs . I was using the Thors with my Orions before going to the Rythmiks.

AJ

AJ,

I am curious if you still use Thors in your system.

Cheers,

Brian

Rythmik Audio

[rythmikaudio]

Originally posted by paulspencer
Recently the subwoofer market has become a lot more competitive and drivers which are articulate and accurate are much more abundant. If you really want a SQ sub, then I'd recommend that you look at drivers which have:

* XBL2 or an alternative technology to get a flat BL curve like some of the better TC sounds drivers
* shorting rings
* servo system

You don't necessarily need all that in one driver, but I would not consider anything which doesn't have one of those 3 to be a fairly average choice.

The new PE Dayton driver with shorting rings looks very good. Worth considering. The Rythmik kit also looks excellent, although unfornate that you need to get the amp from them as well if you are in another country. Also consider the TC2+ and there are some new XBL2 subs from Acoustic Visions which are apparently similar to the Shiva and Tempest in parameters, but with a superior motor design.

I wish there was so much choice of SPL/SQ low distortion subs when I was buying!

Paul,

AJ mentioned fast car in connection with fast bass in another post. That gives me an inspiration on how to compare how various distortion behaves. There are basically 2 types of distortion in speaker drivers: memoryless (such as BL nonlinearity) and with memory (such as spider/surround creep effect). If we say music is like a winding road and a subwoofer driver is like a car, then I would say the BL non-linearity is like a steering with non-linearity at steering extremes and spider/surround creep effect is like body roll characteristic of the car. While we can easily adjust for (or get used to) the steering nonlinearity, it is very hard to adjust for a body roll, in particular when you make consecutive turns. At each turn, the body roll puts the car in a different state, depends on how close those turns are and ....etc.

In my view, it is more important to reduce the spider/surround memory effect than BL non-linearity. That does not mean I care less. Our drivers have a 1.8"-2.0" long sensing coil to improve the BL linearity in the servo feedback signal. Essentially, we want the efficiency of shorter coil and BL linearity of longer coil.

Spider/surround creep is just one of many memory effects in a driver. Another one is thermal memory effect. If you do a google search, there are some academic papers on thermal memory effect of electrical circuit. And not surprising, the conclusion of those papers is that the thermal memory effect is most prominent at low frequency.


-Brian

[AJinFLA]

Hi Brian,

the Thors were assimilated into the dipole (sub) sections used in my Orion "Mutants". Used in conjunction with your Rythmiks (below 40hz), my SPL capability rises quite a bit (my neighbors love this ) from the standard 2x10 Peerless.
I like the Rythmiks enough to where they will still be part of my next design - when I finally replace my Mutants.

Cheers,

AJ

[paulspencer]

Brian,

I'd be interested to see some comparisons of your subs with some other low distortion subs to show both linear and non linear distortion performance. I'd expect the Rythmik kit to outperform most subs quite easily, but what I'm really curious to know is how they compare to XBL2 subs!

[Soundmonster]

I'm in the same boat here, looking at the possibility of building a subwoofer or two and wonder how the 15" Rythmik kit compares to building a 15" kit using the TC Sounds tc2000 driver. I know an amp would need to be purchased and possibly an EQ also to get level response down to about 20Hz or so if I went the TC Sounds route.

Does anybody have any experience with the kits offered by a company called ACI from a few years ago? How would those sub kits or the commercial versions they offer now compare the the 15" Rythmik kits available
today?

Thanks in advance for any and all suggestions/info/help

Charlie

[audioferret]

I absolutely love mine... I have heard none better.