I can't get input level right in REW. RME ASIO, Focusrite ISA 428mkii Preamp, and Behringer ECM8000.

[SSC]

Hi,

After years of holding off measuring my small home recording and mixing setup, I thought I would give it a go today. I am borrowing a Behringer ECM8000 off a mate.

I have managed to calibrate my soundcard which is a RME AIO Pro, also the output in REW seems fine I can get a nice 75dB on my analog SPL meter in the room. but man, I've spent hours and hours trying to get the input level right! I'm at a right loss.

For some reason when I try to match the volume input to the -12dbfs signal, I have to have my preamp level at a crazy volume to get a -30 reading, talking maxed out. It's a ISA 428 mkii, so maxed out is very, very high gain!

The ECM8000 works fine in Pro Tools and is working at normal levels, so can rule out phantom power, mic cable, and routing.

Just a heads up, I'm on Windows 11, latest version of REW installed. My soundcard is a RME AIO Pro. My setup is synced at 96kHz.

Any ideas what I am doing wrong? I've watched so many vids on REW, but no one seems to show a solve for the the problem I am experiencing.

Any help would be great and much appreciated!

Cheers!

 

[SSC]

Just to point out incase your wondering, the RME AIO Pro is a pcie card type. No built in preamps, so need to use my ISA 428.

 

[SSC]

My REW settings are-

Drivers-
ASIO

Sample Rate-
96 kHz

ASIO Device-
ASIO Hammerfall DSP

Output-
1. AIO Analog 1 (Channel 1 on RME output. This goes out to my monitor controller L into my left speaker.)

Input-
1. AIO Analog 1 (channel 1 on RME input. The Behringer ECM8000 is connected to Channel 1 on my 428 into AIO Analog 1 of the AIO Pro.)

Sweep Level-
-12.0 dBFS

Ticked-
Treat 32-bit data as 24-bit

Soundcard calibration-
RME AIO Pro.cal

 

[John Mulcahy]

Level matching is for line inputs (e.g. with a loopback for a calibration measurement). With a mic you'll typically get input levels around -50 dBFS or thereabouts.

 

[SSC]

Hi,

Thanks for taking the time getting back!

Sorry, I am now way a tech head. more wired on the creative side!

When the white noise is playing at 75db in my room, what level do I aim for on the input, -50 dBFS?

Thanks.

 

[John Mulcahy]

Yes, that should be fine.

 

[SSC]

Cool! Man, I spent all day trying to figure out what was going on.

I will have another shot now!

Cheers for the help!

 

[SSC]

Right, so I have had a shot at it again, aimed for 50-55dbfs. Seemed much better!

Is there a way I can upload the .mdat file on here, just too double check If I done this right?

 

[SSC]

Right, so I have had a shot at it again, aimed for 50-55dbfs. Seemed much better!

Is there a way I can upload the .mdat file on here, just too double check If I done this right?

Just attached. If anyone could check to see if I done the sweeps right, that would be great!

My room ain't looking cool, lol, if I'm reading right.

Cheers!

 

[John Mulcahy]

Measurements have worked well. I've seen much, much worse room results. Very uniform decays above 300 Hz, and very damped up there. Low end is pretty ragged but most are. For acoustic work single 256k sweeps are fine, you don't need two 512k. 48 kHz sampling is also sufficient.

 

[SSC]

Thanks for taking the time to take a look! Glad I got usable measurements.

Really? I'm pleased to hear it's not a complete disaster then!

My room is tiny it's 7ft 9" height, 13ft.8" length and the front wall where my speakers are is 8ft.5" wide. It's a frankenstien of a room! No wall is the same material, plus airing cupbaord in one corner, entrance in another, 1 small window, 1 large window and to top it off it's upstairs, fully carpeted and the celling is old compressed cardboard type, really thin! I have a drum kit rammed in too, plus a single bed aswell. Standard UK bedroom!

I do have a bit of treatment, but for years have just been randomly putting it up. This week I switched too-

GIK Tri Traps behind my speakers in the front wall corners
Monster Trap cloud (7" with 5" gap) between my listening postion and speakers.
Monster Trap and 2, 4" GIK panels on the back wall.
Monster Trap on a keyboard stand on the door enterence at back corner (can't keep it there annoying I have to get out sometimes!)
Right back corner I have a bed rammed in, but can't get too much of the corner due to needing the bed.
Refection points, just 2, 2" panels.

Could the over dampend results be due to fully carpeted room and curtains on the small and big window? I can't do much on the carpet but can easy open curtains.

I have one Monster trap and 2, 4" and 2" panels spare. If you could recommend anywhere worth trying, if the results show anything? I'm guessing the 2" panels may dampend even more highs/mids?

Thanks a lot for telling me about the mic level, really aprreciated! Can't wait to get testing again tomorrow.

 

[SSC]

Ah, and tomorrow I will use 1 sweep at 256k.

My setup is all syned up to 96kHz. Is 96kHz still fine to use?

Thanks again!

 

[SSC]

I'll have to try a test without the jazz size drumkit in the room too!

 

[John Mulcahy]

Yes, fine to use 96 kHz.

 

[SSC]

Hi,

Thanks for getting back on that.

I'v been testing and re arrange all day again. If you have a spare 5, are these results any better? The lowend seems more present. I can actually here 80hz bass drums! Trouble is it's a lot further away from my screen. Don't think my neck and eyes can handle it for too long. My old postion from speakers was 41", this is 56".

Thanks again for the help so far!

 

[SSC]

Now I finally know why my left side always sounds shifted in the centre, stereo image! Bass and drum, mono shoots to the left.

 

[John Mulcahy]

A bit better. You can experiment with positioning more quickly by playing Pink periodic noise from the signal generator while watching the response on the RTA with the settings below.

 

[SSC]

Hi John,

Thanks for getting back again and cheers for the RTA test tip! I used it today.

I have had another shot. Probs be the last for a while as everyone is getting annoyed with my clutter everywhere for 3 days!

I found out I was setting pretty much dead centre between the floor and celling, so managed to lower my speakers 3 inch or so. Still a workable height. Their PMC Result6's. Ony had them a few weeks.

I took out a few 2" panels as I don't think their doing much help.

This postion sounds the best to my ears in my sweet/mix spot which is 46" away from speakers. Their 6" away from the front wall, 19.5" from tweeter. So I am now setting around 4ft 10" from the front wall. Total room length is 13ft 8".

Sorry to keep asking, but do this results seem any better. I done both sides, with and witout drum kit.

Cheers John!

 

[John Mulcahy]

They're broadly similar, go with what sounds best.

 

[SSC]

Thanks for checking! I can hear a litlle more lowend now. I will just keep experimenting with placement and postion and try working out how to read the measurements now. Seems to make more difference than anything else! Most of my panels are kind of too thin really, plus the room is really small.

Thanks again for all the help! Really appreciated.

 

[steve138]

@ SSC check Acoustics Insider on his web site and YouTube. He's an acoustics / recording engineer who helps folks in your situation with home recording / mixing room acoustics. He offers plans for DIY absorber panels too.
Steve

 

[SSC]

@ SSC check Acoustics Insider on his web site and YouTube. He's an acoustics / recording engineer who helps folks in your situation with home recording / mixing room acoustics. He offers plans for DIY absorber panels too.
Steve

Hi Steve,

Thanks for the heads up on Acoustics Insider. I have actually been watching a few of his videos this past week or so. Some really cool info, and on his site too.

I have now got my speakers postioned a little better for me and my room. It's surprising how even a few inches can make quite a difference!

John's help on here has been great. The using the RTA for help with placement has been a great guide and really useful tip!

Cheers.