Official DataSat RS20i thread. (Setup Tips, Questions,General Info, etc) - Page 9

If the bass from the mains is uniform to all the seats of interest, I might agree. But how often is that the case in typical consumer rooms? The huge benefit of subwoofers in general and multiple subs in particular (all driven in mono) is that the seat-to-seat uniformity can be dramatically improved. Let alone the headroom that in JapanDave's case would be unlikely to be matched by any main speakers.

Improved uniformity makes it much easier to EQ (manual or automatic). Imagine moving the measurement mic from seat to seat and seeing similar peaks & dips. Would make Dirac very happy.

Those are not strictly the frequency responses of the sound in any particular seat. Those curves confirm that Dirac has successfully inverted the computed error response (the "before" curve) in conformance with the desired target curve.

The error response is derived by sampling several locations (typ 9), and analyzing the nature of the direct and reflected sounds caused by room acoustics. If it detects certain errors such as nulls that it decides it cannot, or should not attempt to correct, they will not be included in the error response.

You'd have to measure the responses with more traditional tools to really know the response at a given seat.

Lol. Adding minidisc would be awesome but I doubt it helps your sub setup!

Delays are part of output settings and you can do them to 0.1ms per channel. By combining with individual channel trim in routing you have everything you need for ultra accurate setup without adding any extra boxes

Dave, I'm guessing you mean miniDSP? If so, you don't need it because that functionality should be built into your RS29i.

No delays are part of the output setup so you can have as many channels as you want on the same input but with different delays. This related to cross over setup for main channels which is why it lives in output.

Yes that is exactly what I am saying!

Little tip, use the cross over I'd to number the subs 1-4 as it makes it even easier to identify them when you move over to the channel delay page.

And the channel trims in the above image are where you have to do the levels for the individual subs which IS very annoying.

Levels are on the output but routing and delays are on the output.

Stupid iPhone.

Should say channel levels are on the input but delays and routing are part of the output profile.

Since the mono sub config is treated as one input channel by the rs20 you have to do individual channel trims to level match the subs and then use the level of channel 4 to match the group to the other speakers in the system.

That will depend entirely on your own system layout and is impacted by performance, boundary effects, physical proximity and more.

Dave,

Indeed. If you have all 4 subs on sub chan 4, then when you adjust the trim level in Audio Levels you'll adjust the level on all 4 subs.

But prior to this you need to ensure every sub is firing at the same spl at the MLP, independently. This could be done in two ways. Once you have pink noise playing in each sub individually you can use the gains on the subs to gain an even response or you can increase or decrease db volume in Routings and crossovers.

Note that unless all of the of the subs are placed symmetrically in a symmetrical room and the listener is at an axis of symmetry (I don't know if this is the case as I haven't been fully following this thread), this does not yield a predictable summed response.

You can verify by checking response at the listening with 1/2/3/4 subs; the output should increase across the passband every time you add one.

It looks like it will.

This is how I understand it:

Individual channel levels, delays and routing are all in the output profile. Overall group surround levels and surround delays are in the input profile.

Crossovers can be set in Dirac, Routing, and BM. I believe they all add together.

Individual input delays and output delays can be set separately via the Delay menu.

Input levels are set on the Levels menu. Output trims are set on the Routing menu.

Input digital levels are set in the Levels menu but only if the digital volume control is engaged. Have not tested the if the output level on the Routing menu will work with digital outputs.

Of course we can eq via Dirac, graphic or parametric.

Complicated? It certainly is.
Versatile and flexible. Absolutely.

For quick and rough measurements you can plug your mic into the XLR mic input on the back of the Datasat, place you mic in the LP, choose the EQ menu and send out pink noise. The Datasat screen will show you a 1/3 octave graphic frequency response. See the manual for more details.

Frequency response is only one of several parameters you want to measure. That is why you need a full measurement suite like REW.

On the Levels menu you can adjust the LFE channel (and the others) in .5dB steps, overall plus 10dB to minus 20dB. There is also a -10dB LFE setting on the decoder menu but it does not currently work in all scenarios but Datasat has promised to fix it.

Edit: corrected range thanks to djnickuk in following post.
Edited by GGA - 1/21/13 at 3:40pm

Just to correct one point, in the levels menu you can plus 10 and minus 20.

Actually,

The RTA built into the RS20i is a pretty good instrument as far as RTAs go. It meets the needs of traditional installers which is who it was targeting. But then again REW, OmniMic, TrueRTA, SpectraPLUS and Smaart software packages do a lot more than traditonal RTAs.
_________________
Best Regards,
Carl Huff