16 channel audio interface for use with REW

[Samazar]

I know REW can be upgraded to work with multiple analogue mics via an ASIO enabled audio interface. I am interested in using REW with 15 mics on stands such that I can obtain 15 measurements simultaneously from a single REW sweep.

If one uses an Apple laptop, is ASIO required?

After some research I have found the following 16 channel audio interfaces that may work well:-

1. The Behringer XR18 - This seems to have an ASIO based driver but reviews mention the fact that that the in-built WiFi is not effective and the interface is dated and not that nice. Not sure if it has phantom power on the mic interfaces.

2. Allen & Heath CQ-20B - This seems to be a really nice audio interface with great software and a nice interface. Not sure if it has phantom power on the mic interfaces.


Please Note: I don't need any extra features, all I need is a simple interface that lets me use at least 15 analogue mics with REW with the ability to adjust the levels of each mic.

Would anyone know of any other brands or Chinese brands that are cost effective. It's important that it works flawlessly with REW. I do appreciate a nice interface if it is controlled from an app.

Any suggestions for reasonably priced condenser mics? I do like the UMIK-1 but from what I understand, REW does not support multiple USB mics. Hence, I am looking at analogue condenser mics that come with a 90-degree calibration file and are as good as the UMIK-1 or 2, especially for measurements below the transition frequency although good full bandwidth measurements are always useful. The MM1 by Beyerdynamics is far too expensive and the EMM-6 by Dayton Audio is questionable although they may have resolved all the issues pertaining to reliability and calibration file anomalies.

In a nutshell, I'm using an Apple laptop and need a 16 channel audio interface with phantom power for 15 analogue mics - in the most cost effective manner possible without necessarily compromising quality.

Any input from fellow members and those that have technical insight will be appreciated.

 

[John Mulcahy]

ASIO is not required to use multiple inputs. Below about 1 kHz the mics remain omni, so you don't need a 90 degree cal file if low frequencies are the main interest. MiniDSP's 90 degree files are generated by processing the on-axis file.

 

[Samazar]

Thank you John, I'm glad to learn that ASIO and the 90 degree cal files are not needed for low frequency work. However, if the 90 degree cal files are available is it possible to load 15 cal files within REW?

Once I have all the mics in position, I suppose I would have to adjust each mic level within the audio interface software to ensure a good signal level. Is it better to do this by using the SPL meter within REW?

Any recommendations in terms of a simple and cost effective 16-channel audio interface?

What mics do you think I should get? Any new cost-effective analogue mics that are as good as the UMIK-1?

 

[John Mulcahy]

You can load a separate cal file for every input of an interface. I'm not familiar with the interface or mic market overall, sorry.

 

[Samazar]

Thank you John, I really appreciate your input. Hoping fellow forum members who may have tried something similar can provide some advice.

You are right though, saw some mic comparison results posted online and they seem identical below 1kHz.

 

[Samazar]

Hi John, I have a question, is it possible to assign and label each channel in a multi-channel measurement in order to identify each measurement with their associated mics?

 

[John Mulcahy]

Individual measurements of a multi-input measurement have the input index appended to the measurement name, with 1 being the first input so they are ...-1, ...-2 etc.

 

[Michael Boeker]

I have several Motu interfaces and really like them. You could go with a Motu Stage-B16. It has 16 mic inputs with phantom power.

 

[Samazar]

I have several Motu interfaces and really like them. You could go with a Motu Stage-B16. It has 16 mic inputs with phantom power.

Very nice but far too expensive considering that i want an audio interface just to connect mics in order to take measurements. All I need is multiple mic inputs, phantom power and the ability to control levels. I will never use the extra features,

Any suggestions?

 

[Samazar]

One thing I have noticed is that the simple ADAT audio interfaces such as the Behringer ADA8200 offers eight mic input preamps, +48V phantom power and level knobs. This is ideal as I don't need any outputs. However, this unit does not have a USB interface to connect to an Apple laptop (MacBook Pro with OS 10.13.6). Is there any way to connect two of these ADA8200 units using an ADAT to USB converter or adapter?

These ADAT expander units are designed to link up to mainstream audio interfaces that do have a USB and ADAT interfaces but are expensive and come with features that I don't need.

One thing I have learnt after a bit of research is that Mac OS allows the ability to take 2 separate USB audio interfaces via a USB hub and define it as a single aggregate device. Has someone tried this and does it work with REW?

Better still, it would be great to be able to connect two ADA8200 units via a USB to Optical adapter or switch that would provide 16 mic preamps for use with REW running on a Mac.

 

[John Mulcahy]

Very nice but far too expensive considering that i want an audio interface just to connect mics in order to take measurements.

You want to connect 15 mics, that takes your needs outside the realm of low cost products. The TASCAM US-16x08 has 8 mic inputs and is a little more affordable.

 

[Samazar]

You make a good point John, I'm really thinking about my approach...

 

[Dr.OP]

The Audient Evo 16 can accommodate up to 24 inputs and is modular, allowing you to add hardware as needed. One significant advantage is its digital gain feature, which ensures that once you've calibrated your mics, there's no risk of accidentally changing the gain by touching the knob.

I know that gain can be controlled programmatically. Unfortunately it is not integrated with REW. That would be a very cool feature to have.

 

[Samazar]

The Audient Evo 16 can accommodate up to 24 inputs and is modular, allowing you to add hardware as needed. One significant advantage is its digital gain feature, which ensures that once you've calibrated your mics, there's no risk of accidentally changing the gain by touching the knob.

I know that gain can be controlled programmatically. Unfortunately it is not integrated with REW. That would be a very cool feature to have.

This seems like a nice product and love the software and UI. However, I need a single compact console with 16 Mic XLR preamps.

 

[Samazar]

I currently use a UMIK-1 in conjunction with REW. I downloaded the 90 degree cal file which REW remembers and uses for measurements. With this in place, is there any way I can build my own 90 degree cal files for analogue mics within REW?

Found this thread:

How to calibrate mic with rew?

Hi all. I have 2 mics: - Calibated UMIK-1 - Not Calibrated UMC8000 What is the right way to create calibration file for UMC8000:

www.avnirvana.com

Input from John:

You can do a substitution calibration, making a measurement with each mic in turn from exactly the same position (usually best close to a source) and then using the All SPL trace arithmetic A/B to calculate the ratio of the responses. Probably best using magnitude-only data for the ratio, which you can make from the measurements by selecting each in turn (with no other measurement selected) and using the "Average the responses" button which will produce a magnitude-only copy. The UMIK-1 measurement needs to use the UMIK-1 cal file. Levels should be manually aligned to match at 1 kHz.

Is there a step by step video for this?