I would measure that separately with REW + timing reference option. I would also experiment with different delays to get the best response over the XO for the fronts. Then run RP.

Or, you can just add a couple ms of distance. You can also ask the sub manufacturer about their internal DSP delay.

I've had horrible luck with Dirac Live setting the sub distance automatically, so my preference is to have manual control over the sub delay.

Yes to the first part according to Lyngdorf, see previous posts from the last few days.

Yes, since RP sweeps the channels as sub+speaker.

@AV_mike
Questions:-
Does Room Perfect electronically/acoustically measure the distances/delays to all connected speakers?

RP requires you to manually measure (with tape) distances and enter them prior to running RP. I don't know if RP measures to verify & optimize phase. I suspect it does.

Does RP calculate/set the optimum crossover frequency for each group/pair of speakers?

Unknown. It may very well do so, but within the confines of what you have entered manually.

Does RP measure the full range response of all mains/satellites/sub-woofers?

No, you must manually select speaker high-pass and subwoofer low-pass according to their capabilities.

Does RP select the optimum crossover slope to suit each speaker group/pair response?

Unknown. It may very well do so, but within the confines of what you have entered manually.


Does the user have to pre-select the speaker groupings that will employ each sub-woofer channel (LFE, AUX1, AUX2, etc)?

No, this is predetermined based on how you configure bass management.

The user's manual does a good job describing how bass management/routing works. http://lyngdorf.com/mp-50/

@Marc Alexander
Thanks for the detailed reply - the bass management/routing looks very capable.

Regards, Mike.

I just realized there's a wrinkle, at least for me, in the BM scheme.

If I'm understanding correctly, if F and R subs are assigned, whether one will benefit from their combined output and smoother combined response is hit-or-miss; that will occur only when there's the same bass signal in a front and rear channel per the above chart.

And the bass response is likely very different between one and two subs playing.

I sure wish it were possible to assign LFE to two different channels and that RP would make some attempt at optimizing their combined response, or least measure and EQ it.

As it is, those of us with multiple subs on LFE are left to our own devices to do that ourselves.

I have with the DSP on my sub amps, and it's OK but I'm sure the results are far from optimal, as my patience is only good for a day's work.

It is possible. You simply leave LFE unassigned and/or configure the auxiliary subs as +LFE. I'm pretty sure the user's manual discusses this. I find the manual lacking in some areas but bass management is not one of them.

Not that I could see; I looked at every instance of "LFE" and "auxiliary".

Good to know, though.

If set up with two aux subs as LFE, do you know if it plays the test tone through both together and/or individually?

Delete your LFE sub assignment and test with just auxiliary subs. (There is not the +LFE setting I mentioned earlier).

No can do; I'm still just a prospective purchaser.

How many subs will you have? Where are they placed? What speakers and crossover points are you planning to utilize? What layout? x.y.z

Front and rear subs, both mid-wall.

Fronts are 12" woofer/CD; surrounds are Mirage OMD-5's and Omni 150's.

I use 100 Hz XO to minimize stress on the latter; I haven't noticed any localization issues.

I'm considering selling my LS10 and purchasing an MP50. If I do, the only reason would be to have a room correction system that does not require me to hire a professional calibrator to run Dirac. Besides that I am totally satisfied with the sound quality and have no other complaints.

After reading through this thread it appears that running room perfect may not be as user friendly as I hoped. Could an average person be successful running room perfect with optimal results? I'm hoping for something as easy as Audyssey XT32 was with my Marantz 8801.

In my experience, it is very simple to get really good results with RP, and I think most actual owners of the RP-50 would agree with this. At least better results than with Dirac in my case. That said, since I use 4 subs, I found that I can also "help" RP a bit by doing some basic measurement and (at least) level adjustment of the subs before RP but that is not very difficult. If you use the LFE sub option, then RP-50 can do pre-RP sub adjustment for you, but not if you run the front/back corner sub config, as I do. Please also note that many of the questions (and answers) in this forum regarding RP and bass management are "clarifications/investigations" from interested, prospective buyers, but that should not be interpreted as an indication that the actual use is very complex ;-)

RP calibration is very easy. One takes the first measurement at the primary listening position. And then RP says to keep taking more measurements to fill in what it calls RoomKnowledge. The manual suggests where the subsequent measurements should be done. Takes maybe an hour, worse case? Then set back and enjoy the results.

My only peeve is that the mic jack on my Lyngdorf device is on the back so I can't do it as easily/often as I like (my speakers tend to move around). It would be better on the front under a door. (Please note this, Lyngdorf!) Where's the mic jack on the MP-50?

I'm hoping someone here has wired up the MP-50 output triggers with what appears to be 3.5 mm phono plugs.

Can anyone confirm if they are Mono with +12/+5, or Stereo with tip + or negative?

I did search the forum using "trigger", and didn't see anything, nor did my quick look through the included instructions didn't show anything.

Putting on my "cheaters" and using a flashlight, it sure looks like the 3.5 mm trigger has two contacts, so I'm assuming stereo phono 3.5.

There is probably an industry standard, but it never hurts to be careful.

Alex.

(Yes, proud new owner of an MP-50)

Alex, tip is + ring is -. The MP-50 can work with stereo or mono cables. Some devices can work with either stereo or mono, some mono only.

You choose 5V or 12V in the setup menu.

Thanks to all for your feedback regarding the ease of being successful with room perfect. That out of the way, I still have one more concern; that is the negative stygma associated with McIntosh digital gear. There appears to be a large group of users that would not recommend McIntosh pre-pros due to glitches, software issues, and poor response from the factory.

If the MP50 is based on the MX160 should I expect similar issues with Lyngdorf?

It's the other way around - the MX160 is based on the MP50. Same as with McIntosh's other pre-pros - they start with a platform from someone else (the Marantz AV8802 is the basis for the MX151) and apply some tweaks which include superficial things like the nice McIntosh front panel as well as changes to things like the digital to analog conversion. But the core functionality pretty much mirrors the product they use as the start point. Firmware updates typically trickle down from the product they based off of, so the McIntosh version typically won't get new features first.

With the MX160, it may have been the first time a McIntosh version was released first, but Lyngdorf was probably wise to hold off release until the firmware was more mature. Early feedback on the MX160 seemed to be that quite a bit of what many might consider core functionality wasn't ready yet. Just as an example, it took a while for the secondary HDMI outputs to get enabled.

I would like an affordable device such as the Geffen Composite to HDMI (scalar) to use in association with an older LD player so that once and a while I can effortlessly turn on the LD player, and use the Lyngdorf for switching. I would send the audio directly via optical to preserve best sound quality.

http://www.gefen.com/product/composi...MPSVID-2-HDMIS

I am aware from my old days that full blown scalars exist to take relatively poor quality composite video signals from a source like LD that has no other output for video other than S-VHS. (The S-VHS conversion is usually far better quality in any modern TV, PJ or Conversion box, so, no point in using that). I used different scalar products back in the day to massage the image for an old Sony 3 beam CRT G70 projector.

The point then was NOT conversion to HDMI signal, rather line doubling, modifying the image ratios etc......

Now, I'm looking for a simple conversion of the composite signal to HDMI format 1080p (yes, I know that requires scalar processing), but the goal is heavily biased for ease of use. I do not want to spend hours fiddling with a full blown scalar to "perfect" the LD image, I can give up a few % of optimization in favor of a turnkey item that remains invisible in the chain, and allows me to use the Lyngdorf as the central pre/pro to keep things easy.

The PJ is the JVC RS500, it is pretty flexible in handling signals, but I still prefer to send the LD video to the Lyngdorf for ease of processing?

Thoughts?

(Possibly the wrong forum, but given that the Lyngdorf is "different" from more common Pre/Pro in that it has very little flexibility for analog inputs, I think people in this thread may well have encountered and considered this subject, and still demanded a decent level of quality. I think there may be lurkers in this thread pondering this question too)

If you believe that I have to get off my ____ and learn how to program a Harmony, or I-Rule type device so that things are seamless, and that the answer is skip the cheap stuff, and 1) go direct to PJ, fix the WAF with programming remotes etc, or, that there is huge compromise if I don't spend 500 to 1000 on a used scalar of some sort that will give me a clean HDMI signal for the Lyngdorf, I'm open to hearing opinions away from something like the Geffen.

Alex.

Hi, I promised that I would share some measurements since there has been a lot of questions about RP and how it works.
I have also had interesting discussions and exchanges of measurements with @logdog333 - thanks!

I have attached two graphs.
Graph 1: The first shows the results after RP for all channels in a 5.1 setup. Well actually, it is a 5.4 setup since I have 4 subs and I am using the 4 corner sub setup in the MP-50, all of which also output the LFE channel. In this graph you can see the three front channels (L, R, C) combined with the FL and FR sub. Down to about 13 Hz +/- 4dB. Then you also see the LS and RS channels, which are matched with two slightly less powerful subs, so they roll off a bit before the front channels. Still very nice. Finally, you can see the LFE channel, measuring about 10dB more than the rest as it should be :-) I had to apply some smoothing here so that you can distinguish the 6 different graphs..

Graph 2: This is an example of "before and after RP", for my right main channel. In this case without smoothing. As you probably can tell I had a quite serious hump and dip in my LF from 16-40 Hz, which RP took care of nicely. I am also showing a third measurement which is after I applied a +3dB tilt below about 35 Hz. Since I like LF and I think RP is a BIT cautious on LF adjustments. Note that this kind of tilting using the voicing option should probably be used with some caution in general. However, the MP-50 reduced the gain so much during initial level adjustment that I am not worried at all about that.

The measurements are what they are, but how does it sound? The difference in subjective SQ between "before" and "after" is huge in my setup. In particular with regards to how the speakers blend with the subs and "disappear" into one big sound stage. My only slight issue was that RP attenuates the very lowest LF a bit too much for my likings. Not sure why. But easy to fix with voicings...

Note that before RP I did some basic level adjustment of each channel and each sub. Just in case it helps RP (and I think it does). And I should also point out that I have a quite "difficult" room to start with. I have low ceilings and sit too close to a slanted wall/ceiling... so I have some issues in the mid-bass (150-300Hz) that no RP/Dirac/etc can fix but I have tried to improve with acoustic panels in the ceilings. But I suspect that those of you with better rooms than mine can obtain better results. At least if you have similar SVS subs :-)

Also, @logdog333 had some results that do not match mine very well, and we are still debating a bit what the reason might be.

cheers,
Erik

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Erik,
Could you state the crossover (or spkr. type) in the MP-50?
Just trying to know whether the speaker mains, or subs are the dominating factors.
(I tend to leave my main crossovers set very low, near full-range).
Thanks,
Mike

@arisholm
Thank you for sharing the measurements. May I ask what crossover frequency you are using for the measured channels? Even your before RP appears to have a very good main/sub splice - unless the XO is around 30Hz (just kidding).

Regards, Mike.

I will experiment more with this, but currently all crossovers @80 Hz. I also used to have a very low crossover for FL and FR, but not anymore, since I have placed the giant PB-16's just below each main speaker so that sub + main really act and look like one speaker for stereo sources. I found that this works very well in my room.

Erik,

Thanks for the graphs, very interesting and impressive results.

Are the graphs from a single measurement at MLP, or an average of multiple measurement positions?

Yes those graphs are from the MLP. But now that I am literally surrounded by subs the LF is pretty good in the "mother in law" seat as well :-)
Not so for the higher frequencies, but my mother in law cannot hear them anyways!

Great write-up @arisholm ! I need to investigate as well as I should be flat down to 5Hz. Can you post your voicing and its affect on FR?

Thanks to Erik for his hard work measuring the stuff )
As I can see he has about 7-8 Db attenuation on low end as where I had about 20 Db
This looks much better but the tendency is there! ))
And as for me I like to boost flat LF to about +3-6 Db depending on a system and a room. On every speaker (or just on the SUB channel as all the speakers are ALWAYS bass-managed). Gently starting from 120 Hz down to what the system is cabable of
BTW, today I've started setting up the new Trinnov Al16. And it looks promising! But still has it's own "issues"

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New user review posted on the AV Forum.

Interesting write-up. Magic isn't a word id personally use in an objective review.

I noticed someone else stated it was a 16 channel pre-pro where its actually a 12.

Id like to see a dirac live v. room perfect head to head with objective reviewers.

A quibble - if ears/brains, i.e. listening, is involved, it's subjective.

The closest to scientific/objective you can get w/listening is to be able to verify subjective preferences with reproducible test conditions.

I concur although i'd still never use the word "magic" when reviewing anything. The term reminds me of the outlandish claims "magic" cable producers use.

Still .. reviewers should have a list of things they have given both glowing and terrible reviews on. When judging something based on subjective tastes this is the only way to prove objectiveness.