Connecting a subwoofer to a Joule LA-150

Ultimately, best way to do this is to put the BAM between preamp and main power amp so you can use the extra pair of outputs on the Joule Preamp to run to your sub. Is it a perfect solution? Maybe not? But any small loss in performance (generally fullness IMHO) of the BAM from not buffering it is made up for in running a good stereo sub-woofer system (assuming the room is large enough).

I have a customer with such a set-up (Joule Preamp, VZN-100s VSM-MXe's and a 2 channel large sub-woofer system - BAM placed between preamp and the Joule OTLs) and... it sounds great. With a low crossover point on the sub (very flexible Bryston sub crossover is used for the subs) the integration is excellent.

The only other possible set-up I can think of is that if you have a sub or sub system that has some type of DSP xover system that can be programmed to make up for (un- equalize) the BAM's signal in additional to EQing the subs output for smooth response in the room. This would allow the BAM to remain in the tape loop - fully buffered - so you can get the best of both worlds.

With only one source, Don's method works, the other preamp output won't be filtered.

With two sources you are using tape loop on preamp, both ouputs are filtered by BAM. using this configuration the BAM essentially remains between the source and preamp. I can't think of a way to maintain BAM between source and preamp and add subwoofer without it being filtered by BAM on preamp outputs. The BAM would have to go between the preamp and amp.

Yes, with two BAMs you could connect each source to it's own BAM, BAM outs into source ins on preamp, preamp outs won't be filtered. I'm also wondering if you could add a second set of RCA ins and outs to an existing BAM. Both sources would go directly into BAM, out into preamp, no filtering at preamp outputs. I think I asked Bobby about this some years ago, can't recall his comments. You could also use a balanced BAM (has two complete circuit boards), one circuit board for each source, outs into preamp ins. Preamp outs no filtering.

Agree with SNS. If you have only one source, such as a CD player then I suggest putting the BAM between it and the preamp and then using the second outputs of the preamp for the sub. However, I have two sources, CD and Analog so I can't do this. Perhaps using two BAMs could be done? Don

As a side note of possible interest . Jud Barber is releasing a new anniversary preamp dedicated to his late wife Marianne . I think it may be called the LA-300 Marianne Electra . Disclaimer : I am a Joule Electra dealer .

Yes, Don is correct, the second output to the sub will be filtered by the BAM, not good, I forgot. Placing the BAM between the amp and preamp is still not a good idea, the BAM has a pleasant effect on the source's sound, placing it between the preamp and amp negates that. Bobby recommends keeping it between source and preamp. This is one of the reasons I don't use a sub with my Merlins.

Still, it seems I recall hearing about some Merlin owners successfully integrating subs into their system, and keeping BAM between source and preamp. I don't recall the method, perhaps someone else here does.

If you put the BAM in the tape loop then both sets of outputs are filtered and you won't get anything out of using a subwoofer. SNS is correct in that Bobby recommends putting the Bam in the tape loop to buffer it but only if you are not running a sub off the second preamp outputs.

Hello Sns,
So if I understand you correctly you suggest to install BAM in the tape loop of the preamp? ( one set of outputs you use to amp connection (without BAM) and another to subs...I presume also without BAM)
Thank you for clarification
I love this preamp!
Rafael

I would go with Brainwater's solution, I don't think you'll like the sound with the BAM between preamp and amp. Ask Bobby, he'll say the same thing.

I am using a sub with my Joule Lap-150. The second outputs are summed with a Y adapter and run with a single cable to the sub. However, make sure that the BAM is not in the tape loop of the preamp but between the preamp and the amp for this to work correctly. Don

Hi , the second set of outputs will work fine for a sub or pair of stereo subs . Bot sets of outputs are active . If its a single sub , you can use a Y splitter and sum the outputs . The Merlins and the Joule gear work great together , esp the OTLs. You need a fast sub with good timbre capability to mate with the Merlin.... IMO.