Recent content by dcibel

Two matching inputs is ideal, for impedance or measurement with electronic loopback. For Audient products, look at ID14 or ID24 instead. They may bit a bit overkill though, Motu M2 is a solid high price to performance option.

To answer your question on trace arithmetic, it's not a strict magniutde math equation, it includes phase so it is a "vector sum". The two responses 4 and 5 that you added together, include an acoustic timing reference, so there is some significant timing/phase differences between the two...

Glad you were able to make it work, however with the first part of the measurement with mic stationary as you ran downstairs, you will have a heavier weight of that single mic location included in the response averaging. It would be best to be able to . Please post your MDAT file if you can...

Keep in mind USB max length is 16ft by spec, without needing more complex solutions like USB over Ethernet. For room measurements I've always used a laptop. You don't need any high end hardware for REW, any old junker will do. another option would be to use some remote desktop solution to click...

It's possible that the SPL just isn't high enough to reproduce the problem. It's also possible that the problem requires more than a single tone like a sine sweep. For identifying things like rub/buzz, I've found it's often much more easily identified with a multi-tone signal. So you can also...

Invert phase just changes the sign of phase values from + to - and vice versa. Polarity inversion rotates phase by 180 deg. To complete polarity inversion, go to impulse tab, right click on the impulse graph area and select "invert".

Yes, I use the amp for both impedance and SPL, it allows for flexibility of other measurements at higher output levels, for example you could characterize change in impedance at different output levels. I've placed the feeback loop after a speaker crossover to measure the transfer function of a...

Most any USB interface with two matching inputs will be suitable, don't cheap out on an interface that has one mic input and one instrument input. I wouldn't recommend Focusrite due to driver issues under Windows, constant buffer under-runs regardless of settings. For a low cost option there's...

Location of speakers in the room in relation to your listening position will have the biggest impact on volume of each speaker. Same answer though, use REW signal generator, level of each speaker can be set independently in the miniDSP, or use the volume balance slider in the Wiim Pro config...

Need more information. What is the "stereo system"? How is EQ being implemented? Usually speaker level and EQ can be adjusted independently. For example on an AVR, you would simply implement the EQ, then use the SPL meter at listening location to adjust the level of each speaker, most AVRs have...

For anyone interested, I reviewed the J-Box III speaker measurement system here a little while back: https://www.htguide.com/forum/missi...ment-tools-techniques/957531-j-box-iii-review This is a great piece of kit, providing the means of completing impedance measurement and acoustic measurement...

John is quite right, amplifiers that used a bridged output cannot be used with this type of measurement jig. Easy check would be to run output from your audio interface directly to the amp, turn on the Generator in REW with 60Hz size wave. Check the amp output terminals with a multimeter, from...

Why?

I don't see anything changed.

Manual Section of interest: https://www.roomeqwizard.com/help/help_en-GB/html/calsoundcard.html#audioconfig