Soundlab speakers with sub woofers?


Hello, I'm looking for input from folks that have used Soundlab speakers or electrostat speakers with sub woofers. It's thought that the sub woofer needs to be quick in order to keep up with the speed of the panel and integrate seamlessly. Has anyone found a subwoofer(s)that was fast enough to work with an electrostat panel and more specifically Soundlab electrostats? What model of subwoofer worked well and how was the subwoofer integrated into the system?
keithmundy
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Bob - well I always hear that one needs to make sure and have a sub that is fast enough for a panel. Obviously a panel doesn't move very far and woofers move quite a bit so.... I suppose that there is some trick into getting them to integrate smoothly? Not sure, just inquiring. Yes, obviously the amps etc... will definitely play a big role, but when it comes to bass the room appears to be a big part of that puzzle. Moving the speakers seems to be the first option, then treatments, then EQ and/or subs is the way I have come to understand it. Thanks for your response Bob.
"What's the basis for this thinking? Why does speed tend to be brought up when people talk about subwoofers?"

Its not so much speed as it is control. Subs need a lot of power, and if you don't have it the bass loses definition. You get that one note booming type of sound like you find in a HT sub. So when you move away from that sound to a more detailed one like you need for music,the sub sounds faster because its better able to integrate with the other speakers. There's other factors as well, but this is probably the most important issue.

Vandersteen does a really good job explaining all different factors that go into making a sub. If you go to their website you can download owners manuals. Read through a sub manual for a better explanation.
The right amp is what makes for bass on a Sound Lab. Generally speaking, transistors are not a good match. The reason is the Sound Lab, like most other ESLs, has a 10:1 change in impedance over its range, and is over 30 ohms in the bass, making it hard for transistor amps to make power, and it does need the power.

So if you have a transistor amplifier of 600 watts, it will make about 150 watts in the bass region, which means a 150 watt tube amp will be able to keep up with it no problem.

Set up correctly I've heard these speakers shake the walls and I do wonder if a sub is needed, since they can go to 20Hz all by themselves!