USP-1 low & high pass filters

[copperband]

I have been using 80hz on both as suggested by the manual. I would like to play around it a little bit with my new sub. I would like to understand exactly what low & high pass filter mean

Say if I set low pass to 80hz and high pass to 100hz, does that mean anything < 80hz go to my sub and anything > 100hz go to my front speakers? If so do I lose the 80 to 100hz level?

I want to know how to decide what level to choose for low & high pass filter.

[jackfish]

For two channel music listening with the USP-1 I've found that you want to set both of these filters as close to the -3dB point of your loudspeaker's low frequency extension as possible. The UMC-1 will control loudspeaker and subwoofer frequencies when using HT Bypass. For home theater settings in the UMC-1, 80 Hz HP for the front, center and surrounds, and 80 Hz LP for the subwoofer will probably be fine, although experiment by all means.

For the Mirage OMD-15 this would mean 33 Hz. However, the USP-1 only goes down to 50 Hz so I would recommend setting both high and low pass filters to 50 Hz. Set the sub crossover to its highest frequency setting. You might also want to try running the OMD-15s full range as your sub is rated only 5 Hz lower and you might get additional positive bass reinforcement from running the mains full range. I'm talking for music. However, running mains from the USP-1 full range output causes issues for home theater because the HT Bypass only goes through the High Pass outputs.

By setting the high pass filter at a higher frequency than the low pass filter, you don't "lose" all of the frequencies in the "hole" as there are still those frequencies reproduced along the slope of the filters. But such a practice will negatively affect the overall frequency response of the system.

[ansat]

deleted my response. - Got ahead of myself and didnt see the usp and made a umc assumption.

[roadrunner]

Copperband
Jackfish pretty well covered the bases on the HP/LP filters usage on the USP-1. The only thing I can think to add to his post is that if you will want to use HT ByPass set both filters to 50 Hz (with your OMD-15s) and you will have very good sound reproduction for the full frequency range of music.

Very few music recordings have any content below 40 Hz. Using the USP-1's bass management set at 50 Hz you will be dealing will a slope of 12 dB per octave. This means, even using the filters, that you will have decent response from your OMD-15 down to 25 Hz and your sub woofer will cover everything below 50 Hz. You will be getting bass frequencies played in your mains and your sub woofer from 50 Hz to 25 Hz.

Last year a few Lounge members who bought the USP-1 were concerned about using their full range speakers with the HP filter. After trying the filters as noted above, they posted in the Lounge that to their surprise they were very happy with the bass response and no longer feared using their full range speaskers with the HP/LP filters set at 50 Hz. They all said that using the filters produced performance equal to or better than running Full Range. Try it and see how it works for you.

[copperband]

Currently at 80hz for both filter, with the new sub placed next to my left front I feel like most of the bass is from my front, not much from the sub...

Yes I am using the HT bypass, so I will try your suggestion to set both at 50hz and hear how it goes

[Brainsick]

DOes anybody know were the 80Hz mark would be on the USP-1?, mine if i put it at about half way, it sound to bassy coming out of my front speakers, so i have the High Pass at almost 3/4 the way up, and the sub a little past the halfway mark.

[pedrocols]

Oct 16, 2012 19:43:44 GMT -5 Brainsick said:

DOes anybody know were the 80Hz mark would be on the USP-1?, mine if i put it at about half way, it sound to bassy coming out of my front speakers, so i have the High Pass at almost 3/4 the way up, and the sub a little past the halfway mark.

I saw a picture of where the 80hz on the user manual...

[klinemj]

For my USP (which just got replaced by the XSP), I always left the USP x-overs at 50/50. Why? Well, 50/50 was the best compromise I could get...and I am not really joking here.

I would have like to take my fronts lower and not have the sub kick in higher. But, the USP-1 didn't let me. So, I set things at 50/50. This let my fronts run as low as the USP-1 would let them. For the sub, I set it's x-over well above the 50 hz...how high didn't really matter because the USP-1 cut things at 50 hz. I could have effectively done the same if I could have the USP do HT Bypass and full range outs...but it does not allow that.

FYI, this is something I really like about the XSP-1...I can set the fronts and sub to full range or hi/lo pass independently and it all works with the HT Bypass. Then, I can let the sub manage how high it does/does not go via its adjustments.

For the USP and XSP - one wish for is more clear/finer markings on the x-over levels. It is hard to estimate given the coarse markings.

Mark

[jackfish]

[mgbpuff]

Jackfish, how did you determine the 80 hz position? If the setting is linear, then that setting would correspond to 130 hz. Did you use instrumentation?

[monkumonku]

Oct 18, 2012 10:03:16 GMT -5 mgbpuff said:

Jackfish, how did you determine the 80 hz position? If the setting is linear, then that setting would correspond to 130 hz. Did you use instrumentation?

I'm not Jackfish, but I used to have a USP-1 and the manual tells you that the 80 hz position is at 11:00 on the dial for both the high and low pass filters. It would be nice it if were marked more exact on the dial but then with the 12 hz cutoff/rolloff slope I guess it is an inexact science to begin with. But it is the manual that tells you what the position is. I don't think it tells you any other frequencies, however, other than the maximum and minimums.

[copperband]

Oct 17, 2012 8:18:48 GMT -5 jackfish said:

How do you insert this nice picture from the manual?

[mgbpuff]

Thanks, I also have a USP-1, but I boxed it up along with the manual when I got my new XSP-1.
Non-linear dot spacing would help a lot, I suppose. Funny, the XSP-1 manual does not have this little tid bit of info.

[monkumonku]

Oct 18, 2012 11:37:06 GMT -5 mgbpuff said:

Thanks, I also have a USP-1, but I boxed it up along with the manual when I got my new XSP-1.
Non-linear dot spacing would help a lot, I suppose. Funny, the XSP-1 manual does not have this little tid bit of info.

You are right - the XSP-1 manual tells you the range of the dial, but doesn't say anything about what position corresponds to what frequency. I don't know if we are to assume it is the same position as with the USP-1..

[jackfish]

Oct 18, 2012 10:03:16 GMT -5 mgbpuff said:

Jackfish, how did you determine the 80 hz position? If the setting is linear, then that setting would correspond to 130 hz. Did you use instrumentation?

It is a diagram directly from the manual. The dial increments are not linear.

Oct 18, 2012 11:13:00 GMT -5 copperband said:

How do you insert this nice picture from the manual?

I used Omniformat to convert the .pdf page from the manual to a jpeg, and then cropped out the diagram with Gimp.