[AUDFILE74]

hi guys, has anyone had a chance to play  with these yet? i know eric and danny love them but i want to hear some more opinions.

[IanLane]

Hi, Just saw this now. I am surprised no-one has replied before.

I run one A370PEQ/ two OB 12 drivers per channel as push-pull dipole subs in flat baffles under my old Quads. (I have temporarily fitted side baffles from top to floor)

On the A370PEQs I have set the sub levels by ear and the phase shift as zero with the parametric eq bypassed. I expect to make some meaningful adjustments  once I get hold of a pink noise generator and RTA.  After much deliberation I chose the crossover at 80 Hz as a better match for the Quads than 160 Hz.

From my experience over the last couple of months I can say that the claims made by Danny and Brian are not exaggerated. I think their servo-dipole sub system is a seriously good product and a screaming bargain.

I hear all the usual desirable bass qualities- e.g. tight deep and very clear with quite decent mid-bass wallop. So far I have little to complain regarding integration with the Quads, although I anticipate some improvements here with phase adjustment.

There are significant improvements in overall headroom and midrange dynamics and transparency as wel as a more spacious soundstage. Of course loudness in my system will always be ultimately limited by the Quads themselves but it is loud enough for me, and I like rock blues and big orchestral music.

Hope this helps.   

[AUDFILE74]

thanks ian, i appreciate you taking time to answer my questions. i was curious, have you thought about the velodyne sms-1? for the price it is ridiculously good:

http://velodyne.com/products/product.aspx?ID=15&sid=886v751d

it may make dialing in the subs a tad easier. i am looking to get one ( along with the mic5 setup)when i get the subs. i want to run a setup like yours .i am debating if 3perside will do better than 2 perside.

[IanLane]

I have not seriously looked into these products, although I think DSP, particularly for bass/room interactions. is a good thing in principle -  as long as you can keep it out of the rest of the system! ( I am almost an analog purist!) I consider Velodyne to be one of the more sophisticated manufacturers of subwoofer systems so the product looks promising.

Please note that I am no expert in these matters.

Dipole bass overcomes quite a lot of the bass boom/overhang problems from both box and room modes. A single frequency parametric adjustment, such as that available on the A370 PEQ, may work very well particularly for the most significant of the lowest frequency problem modes, although a range of adjustments at different frequencies should be better, again in principle. I am told that parametric eq can be tricky in practice.

The A370 control features are already quite versatile in regard to low frequency damping and extension. I use the lowest(nominal 14 Hz) extension with the highest damping. (I also mainly play vinyl and the rumble filter is quite effective.)

I do not know the speaker system you have in mind. Even though the A370 seems to be optimised to drive four of the GR OB drivers I considered this to be overkill when mated to Quads, and two side by side just fit under them. In theory the "drive" is balanced with a pair (or multiple pairs) of oppositely oriented drivers.

Assuming no-one else here is interested I am happy to continue to correspond with you by PM if you like
 

[AUDFILE74]

that would be great ian. i look forward to hearing from you.shoot me an email when you get a chance.