Belles Ondes : Creative Engineering

User Tools

Site Tools

Trace: • xrvsmr
xrvsmr

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision		Previous revision
xrvsmr [2024/06/17 09:23] – wadminxrvsmr [2024/06/17 12:51] (current) – wadmin
Line 3: Line 3:
 {{drawio>xrmr:main.png}} {{drawio>xrmr:main.png}}
  
 +==== Introduction ====
  
-==== T1 - Inner Noise ====+This document proposes a test procedure and results comparing Behringer XR18 and Midas MR18 performance. 
 + 
 +==== Disclaimers and Claims ==== 
 + 
 +Starting with a general statement: Measurements are done as close as possible to what would be a scientific measurement process (Configuration and tests are documented, are reproducible by a third party, tests results are published, known assumptions and limitations are mentioned as far as possible). 
 + 
 +Now the claims: 
 + 
 +  * **Statement #1** : Measurements are done in recording studio environment. Namely, there is no control on CEM/EMI interfering with measurements apart from standard studio installation best practices in terms of proper ED grounding and shielding.   
 +    * As a consequence, comparing the results is more important that dealing with the RAW value.  
 +  * **Statement #2** : One input and one output are used on each unit, there is only one pair of interface sample tested. Having a pair allows to check for a similar performance on both interface, to rule out obvious erroneous failures on one interface. It is understood that statistically processing those measurement among several interfaces and unit S/Ns would be much better, but is out of scope of this measurement procedure. 
 +    * As a consequence, these results are (1) immune to critical failures on one channel but are (2) prone to specimen bias. 
 +  * **Statement #3** : XR18 has two high impedance instrument inputs which MR18 does not have. For the sake of comparing apples with apples, Input 9/10 and Output 1/2 are used as references on both units. 
 + 
 +Measurement Gear 
 +  * UUTs 
 +    * MR18 S211000533C8H 
 +    * XR18 **XXXXXXXXXXXX** 
 +  * Tools 
 +    * Gen2 Apollo Twin USB 
 +    * XLR Wires / Jack Adapters 
 +    * Room EQ Wizard Rev xxx for measurement 
 + 
 +------------- 
 + 
 +===== Test Procedure ===== 
 + 
 +==== T1 - Inner Noise and THD ==== 
 + 
 +Measure loopback  RTA THD (+N) @1khz + total dynamic range.
  
 === Setup === === Setup ===
 +
 +  * REW in loopback mode, 
 +  * Double shielded XLR as connection 
 +  * on both units, use In-9 and Out-1 
 +
 +Loopback diragram:
  
 {{drawio>xrmr:t11.png}} {{drawio>xrmr:t11.png}}
  
-=== XR18 Measurement ===+=== *R18 Measurement ===
  
-=== MR18 Measurement ===+== -12dBfs / G=0 == 
 +  * Set Inputs Gain to 0dB 
 +  * Set Output level to match a -12dBfs input level 
 +  * Measure RTA and store 
 + 
 +== -12dBfs / G=8dB == 
 +  * Set Inputs Gain to 8dB 
 +  * Set Output level to match a -12dBfs input level 
 +  * Measure RTA and store 
 + 
 +== -12dBfs / G=18dB == 
 +  * Set Inputs Gain to 18dB 
 +  * Set Output level to match a -12dBfs input level 
 +  * Measure RTA and store 
 + 
 +== -12dBfs / G=28dB == 
 +  * Set Inputs Gain to 28dB 
 +  * Set Output level to match a -12dBfs input level 
 +  * Measure RTA and store 
 + 
 +-------------
  
 ==== T2 - External loop comparison ==== ==== T2 - External loop comparison ====
Line 19: Line 75:
  
 {{drawio>xrmr:t21.png}} {{drawio>xrmr:t21.png}}
 +
 +=== *R18 Procedure ===
 +
 +== -12dBfs / G=0 ==
 +  * Set Inputs Gain to 0dB
 +  * Set Output level to match a -12dBfs input level
 +  * Measure Transfer function and store
 +
 +== -12dBfs / G=8dB ==
 +  * Set Inputs Gain to 8dB
 +  * Set Output level to match a -12dBfs input level
 +  * Measure Transfer function and store
 +
 +== -12dBfs / G=18dB ==
 +  * Set Inputs Gain to 18dB
 +  * Set Output level to match a -12dBfs input level
 +  * Measure Transfer function and store
 +
 +== -12dBfs / G=28dB ==
 +  * Set Inputs Gain to 28dB
 +  * Set Output level to match a -12dBfs input level
 +  * Measure Transfer function and store
 +
 +===== Test results =====
 +
 +==== T1 - Inner noise and THD ====
 +
 +=== XR18 Results ===
 +
 +== -12dBfs / G=0 ==
 +
 +== -12dBfs / G=8dB ==
 +
 +== -12dBfs / G=18dB ==
 +
 +== -12dBfs / G=28dB ==
 +
 +=== MR18 Results ===
 +
 +== -12dBfs / G=0 ==
 +
 +== -12dBfs / G=8dB ==
 +
 +== -12dBfs / G=18dB ==
 +
 +== -12dBfs / G=28dB ==
 +
 +==== T2 - Transfer function ====
 +
 +=== XR18 Results ===
 +
 +== -12dBfs / G=0 ==
 +
 +== -12dBfs / G=8dB ==
 +
 +== -12dBfs / G=18dB ==
 +
 +== -12dBfs / G=28dB ==
 +
 +=== MR18 Results ===
 +
 +== -12dBfs / G=0 ==
 +
 +== -12dBfs / G=8dB ==
 +
 +== -12dBfs / G=18dB ==
 +
 +== -12dBfs / G=28dB ==
 +
 +
xrvsmr.1718616228.txt.gz · Last modified: 2024/06/17 09:23 by wadmin