discussion for multichannel (20+) setups: dante, avb, etc

When judging sound quality difference you have to correct for loudness. (Slightly) louder appears to sound better. When you add another speaker pair you are getting a bit more loudness so you have to correct for that.

Yes, that is a 'trap' you can fall into when auditioning speakers or monitors at Guitar Center or similar with their multi-selector panel. The sightly louder speaker is the most impressive, especially since the comparison is usually out in the open and competing with other noise.

Thats because 1) adding the 10th pair of speakers (obviously) doesn't make the same difference as the 2nd pair;

Using a Hauptwerk algorithm where pipes/notes are divvied amongst x number of speakers, I found the magic number to be "4"; 4 stereo pairs to be exact. I've done a few tests and it seems the 5 pair is where the diminishing return starts; adding a the 2nd, 3rd, and 4th pairs you hear a noticeable improvement, especially if you pause to play and audition after each addition.

Since you have a large room, I think the safest way to progress is to get the UMC1820 and to add another 8 channels (plus a subwoofer).

I would caution not to use this interface. It is known to have a buggy driver that is not compatible with certain releases of Windows, especially the later Windows 10 updates. There are so many other interfaces that will sound better and more reliable. If your are opting for Adam monitors don't cheap out on the interface. The later MOTU models rival that of RME.

Danny B.

Since you have a large room, I think the safest way to progress is to get the UMC1820 and to add another 8 channels (plus a subwoofer).

I would caution not to use this interface. It is known to have a buggy driver that is not compatible with certain releases of Windows, especially the later Windows 10 updates. There are so many other interfaces that will sound better and more reliable. If your are opting for Adam monitors don't cheap out on the interface. The later MOTU models rival that of RME.

Danny B.

Motu should be excellent indeed. I have experience with RME and the UMC1820, no problems with buggy drivers for the latter so far, but if it is a known issue, better be careful indeed (do you have a link? I would be interested).

I think DAC performance is not very critical to sound quality. Unless something is very broken, it does not impact the frequency response. Any DAC conversion adds a small amount of noise/distortion, but that's typically at or even far below the threshhold of audiblity.

Agreed josq, all these interfaces all use the same few DAC chips from ESS/Burr Brown etc, so it's mainly in the rest of the hardware where noise, jitter, or poor quality can be introduced but I have a very hard time distinguishing between sound in the few interfaces I have around my house (Focusrite, Motu, M-Audio, and one from Emotiva). Perhaps my speakers aren't good enough to show the difference either. In any case, I've heard far bigger changes in sound quality by focusing on the speaker and partly the room as well. So I'm not suggesting that there are no sonic differences between Behringer and Motu and RME, just that I'm not sure I'd hear the difference myself.

However, driver support, that is indeed a different issue. I do need my organ every Saturday/Sunday to practise so I'm very hesitant to "cheap out", but on the other hand the Motu I've had hasn't been the most stable either. But I haven't read any negative reports about stability with the 24ao which is what I'm currently leaning towards.

Also agreed that there are diminishing returns when adding another pair of speakers. I plan to double my front channels from 6 to 12, and that should really help because each speaker is essentially reproducing half of what it used to be doing. I'm sure that separating the Ambient from Direct samples would improve the clarity.

The rear port issue is interesting, I never clued into that. My current Adam's are front ported. I might try plugging the ports but to be honest, since my crossover is at 80 hz there shouldn't be too much problem with placement, I hope anyway.

I did briefly try sending direct/close ranks to a different speaker group than diffuse/ambient. The abrupt release cutoff and silence from direct semi-dry samples was extremely irritating. Ended up mixing direct + diffuse in the same speaker group and sending different divisions to their own speaker groups** to level the load in a more natural-sounding way. Either way, speakers work less and don't come anywhere near their distortion volume levels.

My amps are set around 1/4 to 1/3 gain, HW per channel levels are -11 to -8 dB to balance between speaker types and positions, organ trim is -20 to -10 dB for most organs, and the house is filled with sound while the HW audio meter shows no bars. I'd prefer to cut amp gains more and increase the HW signal a bit, but the gain knobs get pretty fiddly near the minimum.

** Previously got equally good results sending ranks to speaker groups by pitch and weight, but I got sick of the effort. Multi-selecting ranks from the list by division and mic position is just quicker, but no better sounding. Laziness also led me to use dynamic random bus allocation, after wasting time setting note offsets for each rank.

That actually makes sense now that you describe it, the direct probably having much less reverb tail volume.

Hmm. I might try it anyway. It might depend on the sample used, and what you used for volume on each? One of my samples you can set the ambient independent of the direct (both can be 100%, for example), whereas my other main sample is a balance style switch which I'm not as fond of as it takes away/fades out the direct the more ambient you add.

But yes, if that doesn't work, I will definitely try separating by division.

You might make different routing decisions for each sampleset.

I did briefly try sending direct/close ranks to a different speaker group than diffuse/ambient. The abrupt release cutoff and silence from direct semi-dry samples was extremely irritating. Ended up mixing direct + diffuse in the same speaker group and sending different divisions to their own speaker groups** to level the load in a more natural-sounding way.

My observation is quite opposite. Seperating all the perspectives as i did improved the sound a lot

I did not find the abrupt cutoff irritating , but it might be that in my setup this is less obvious to hear .Or the dry samples in my sets are not as dry as the samples you experimented with.

This is my setup.

My front speakers for the direct /dry perspective are situated at ear height on 11 and 1 o'clock, the diffuse perspective speakers(side front) are located at 10 and 2 o'clock at the side near the ceiling and the distant perspective (side rear) speakers are at 9 and 3 o'clock also near the ceiling and also rear speakers at 7 and 5 o'clock. So the forward backward placement of the speakers resembles the position of the recording mics in the church.

When i play, the direct persperspective gives a very detailed reproduction off the pipe through the front speakers, releasing the note gives a natural fade out off the note through the remaining three wet perspectives, to the front/side and left, right/ side and rears i never experiencend a abrupt cutoff.

But i guess all depends on how your system is setup.

Jan