ULS-15: Using both high and low level inputs

[iga123]

Please tell me if this setup would work or not:

Let's assume I've got separate pre/pro and power amp. I'm thinking about connecting both HSU ULS-15 high level (speaker) inputs to power amp's FR/FL speaker outputs and sub's XLR input (left?) to pre/pro SW output.

This way I would use pre/pro as stereo preamp in direct analog mode to listen to stereo sources like external DAC on front speakers with sub. In HT "mode" I would use pre/pro for multi-channel decoding and bass management to feed both high level and low-level LFE output to the sub.

Will this setup work at all? Is it valid/recommended?

Thanks,
George

[JerryMeeker]

This hook-up makes no sense to me at all. What are you trying to accomplish? Are you concerned that there is no bass management when you use your pre/pro's pure stereo mode and want to use the speaker-level inputs to get bass to the ULS-15?

After many hours of comparison between pure analog stereo and digitally processed stereo, I think today's digital processing (especially when you consider Audyssey room correction, Audyssey sub equalization, and bass management) results in a far superior sound.

Just my opinion...

[iga123]

This hook-up makes no sense to me at all. What are you trying to accomplish? Are you concerned that there is no bass management when you use your pre/pro's pure stereo mode and want to use the speaker-level inputs to get bass to the ULS-15?


You've got the idea right, but why doesn't it make sense? In pure stereo mode there is no bass management because bass management is done in digital domain. If I use low level sub output only, FR/FL+sub in stereo mode means that the analog input signal would be digitized by receiver first, DSP processed and then converted back to analog once again. No matter how good the process is, I don't trust it. The alternative is dead simple - hook up the sub to front speaker outputs and you've got your bass augmentation. No processing, simple analog.

And, BTW, I'm talking about just one preamp for this setup - not the separate stereo and HT ones, as Pete suggested - just one receiver (Marantz?) or pre/pro + power amp.

So my question is really simple - how does ULS-15 process its high and low inputs? Is it a sum of both, low only or something else?

Some sub manufacturers disallow simultaneous low + high inputs completely, some have a switch to choose between and some, like REL, say that speaker level input is preferred and using along with low level input is a great idea for exact type of setup I'm thinking about.

[Pete_Hsu]

Hi iga,

I mistakenly thought that you wanted to use one subwoofer for two separate systems (one music system, and one home theater system), so I have deleted my previous post.

One should not use both high level inputs and low level input(s) at the same time on our subwoofers. With an A/V receiver that has bass management, we recommend feeding just one low level input on the sub amp, and we recommend bypassing the internal crossover on the sub amp so that one can make use of all the bass management features on the A/V receiver. Filtering out lower frequencies going to the mains tends to give lower distortion and wider dynamic range, and one can easily adjust distance and channel level to get good integration between main speakers and subwoofer.

Sincerely,

[JerryMeeker]

You've got the idea right, but why doesn't it make sense? .... No matter how good the process is, I don't trust it.

I am only expressing my opinion, and I don't share your distrust of analog to digital conversions. As long as the electronic components are quality units, there are real acoustic benefits to room correction and bass management, yielding results that can be sublime.

However, I can understand that a quality full-range left and right speaker system, placed carefully in a well-treated room can achieve equally sublime results for music in an analog-only setup. In this case, forget the subwoofer...

Good luck with your choice!