What measurement result should you strive for?

Vladimir_1953

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Preamp, Processor or Receiver
ROTEL RC-990
Main Amp
ROTEL RB-991
Universal / Blu-ray / CD Player
DENON DCD-2000AE, ROTEL RCD-991AE
Front Height Speakers
Dynaudio Crafft
What should the impulse response graphics, step response and phase of a perfectly converged 3-way speaker system look like?
Component-wise, left / right and total.
What measurement result should you strive for?
 

Vladimir_1953

New Member
Thread Starter
Joined
Jul 5, 2018
Messages
39
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Preamp, Processor or Receiver
ROTEL RC-990
Main Amp
ROTEL RB-991
Universal / Blu-ray / CD Player
DENON DCD-2000AE, ROTEL RCD-991AE
Front Height Speakers
Dynaudio Crafft
Is this chart perfect?

-car-via-impulse-response-ir-time-align-2014-09-08.jpg


Or are there other options?
 

jtalden

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May 22, 2017
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Arizona, USA
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Preamp, Processor or Receiver
Marantz AV7705 Pre/Pro
Main Amp
VTV 6 chnl NC252MP P-amp x 2
Additional Amp
Behringer DCX2496 x 2
Universal / Blu-ray / CD Player
OPPO BDP-103 Universal Player
Front Speakers
DIY SEAS H1456/H1212 Spkr x 5
Subwoofers
DIY JBL 2235H 15" SW x 2
Video Display Device
JVC DLA-X790R
Screen
Da-Lite Da-Snap 39105V - 92"
The current relative delay is correct if the acoustic XO follows an idealized LR24 or LR48 shape for instance. Most acoustic XOs deviate from one of the idealized XO situations however so some minor delay adjustment may be needed to optimize the timing for a particular situation. The difference may be significant or it may not be.
Look at the SPL support that this delay setting provides through the XO frequency range by using an overlay of L MLCD, L MB and 'A + B' arithmetic summation of those 2 (or a measurement of both drivers operating together). The overlay of those 3 traces will show the SPL support. This is easiest to see with 1/3 or 1/6 smoothing applied. If there is good SPL support in the XO range then the delay setting is good. If not, then delay the L MB just enough more in order to get the best SPL in that XO range. You can then look at the R channel and do the same. The delay needed for the 2 channels should agree. If they differ significantly then the room effects are interfering too much.

I you want a specific opinion on the current setting, just post the mdat containing those 4 measurements.
XO Timing.jpg
 
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