Wireless subwoofer question???

Hi Al,

Thanks a million, I will look into it. The ES 250 you looked at is the exact one I have.

thanks,
Bob

I took a look at the manual for a couple of the JBL wireless subs. I think that you could accomplish what you want with an inexpensive mixer, such as this one. The manufacturer's page on it is here. Considering that the sonic quality of the mixer at frequencies above the deep bass region would be irrelevant, it could very well be just the ticket despite its very low price.

You would connect it to the "no. 2" L&R outputs of your preamp, and connect its output to the RCA input of the wireless transmitter. You would turn on the low pass filter the sub provides for its wireless input, of course.

In setting the level controls on the mixer, you would want to be cautious in turning them up because it provides a maximum gain of 40 db, which is WAY too high when the source is the output of a preamp. Since it is intended for use with line-level sources such as CD players, though, it presumably can handle the output voltages of a preamp without any problems if the level control is kept in the lower part of its range. To fully confirm that, though, it might be a good idea to contact the manufacturer and ask them how much input voltage the mixer can handle before it overloads and distorts.

Regards,
-- Al

Hi Almarg & Eli,

Thanks so much for the help! Almarg, it seems then the best is just to keep it running via the rca cables, so that's what
I'll do for now with this sub. It is btw a new JBL sub, and I
bought it with the intent of just using it for movies alone, but it does blend really darn well for music. Oh well, I'll just keep the long run of wires.

Thanks again!

Eli, note that the question concerns how to deal with the fact that the wireless transmitter to which the preamp would be connected only provides a single input connector. Also note, as indicated at the link I provided, that the preamp already provides two pairs of outputs.

Also, using a y-adapter as you described does not "split the output voltage." It reduces the value of the load impedance seen by the preamp, since in that situation the preamp output will see the input impedances of two components in parallel. If that reduced load impedance is still much higher than the preamp's output impedance, the reduction in voltage will be negligible. That would certainly be the case with the Peachtree Nova, which as I had mentioned has a very low output impedance.

Regards,
-- Al

you will need 2 "Y" splitters, single male to 2 female.
Connect each male end to the Pre-out (L/R), you now have 2 Left and 2 Right, variable outputs from the Pre-Amp.
You have effectivly split the output voltage, but you can compensate with the volume control if needed.
Once you have the subwoofer at an adeqate level, the only adjustment on the sub needed, may be to switch between Music and H/T modes on the subwoofer.

What kind of input connector is provided on the transmitter? If it is a 1/4" or 1/8" type, rather than an RCA or other connector, it may be designed to accept stereo inputs, which the sub itself would then sum to mono.

If it is an RCA connector, I'm not certain that using a y-adapter on your preamp outputs would be a good idea. Based on the specs shown here, it can be inferred that fortunately the two sets of pre-outs PROBABLY are separately buffered, so that connecting L & R together on one set of outputs would probably not cause the signals going from the other set to the main amplifier and speakers to become mono. However, the specified output impedances, especially on output no. 2, are very low, which leads me to be uncertain as to how well they would handle being shorted together. And it appears that output no. 2 is a lower quality one (driven from an op amp), which is therefore not the one you would want to use for your main speakers.

Also, it might be helpful for you to indicate the make and model of the particular sub.

Regards,
-- Al