REW for Home Cinema setup if AVR is >15m away from output room

[creative_vision]

Hi all, complete newbie here so please be gentle! I've read the FAQ and understand this forum is measurement-focused which is exactly what I need.

I have a home cinema room I'm trying to properly calibrate for the first time. The complication is that my AVR lives in a utility room approximately 15 metres away from the cinema room, with all speaker cables running through the walls.

So I can't easily connect a laptop directly to the receiver unless I use really long cables, which I believe - but correct me if I'm wrong - is not ideal?

Strangely both my subwoofers died a few weeks ago (I have no idea why, how or when exactly as hadn't used the room for a couple of months or so) ... and now both back from repair so I thought I'd use the opportunity to calibrate the room properly.


My setup:

• Receiver: Yamaha RX-A1060
• Front L/C/R: Monitor Audio CP-WT240LCR (in-wall)
• Surround L/R: Monitor Audio SF3 (in-wall)
• Atmos ceiling L/R: Monitor Audio CP-CT260 (in-ceiling)
• Subwoofer 1: B&W PV1D
• Subwoofer 2: Monitor Audio Radius 390
• Behringer HD400 hum remover
• Mic: MiniDSP UMIK-1 (just purchased!)

Current manual settings:

• FL/FR/C/BL/BR/HL/HR speakers all set to Small
• Crossover 80Hz
• Speaker levels set by original installer who seemed rushed to leave!

My question: I have just installed REW for the very first time and have never used it before. I have my UMIK-1 (still in its box) and ready to go but have no idea where to start.

Could anyone kindly walk me through the first steps for a complete beginner, bearing in mind the unusual complication that my receiver is 15 metres away in a separate room? I want to make sure I'm doing this right from the very beginning rather than ending up ruining the current set up, which is fine but I guess not ideal.

Any advice or a pointer to the most relevant guide for my situation would be hugely appreciated.

Many many thanks in advance!

Best,
Amer
55 Year Old Man Who Loves The Idea Of A Perfectly Calibrated Cinema Room But May Not Even Have The Ears To Appreciate It Any More ... But At Least My Kids Will

 

[digitalfrost]

Put a PC/Laptop with REW installed next to the amp. Use another laptop at the listening position (or any other position) and remote desktop into the 1st machine. I usually measure my PC setup while being somewhere else with a laptop so I don't have to sit in the way, have no way of accidentially moving the microphone and I don't need to listen to the measurements at loud volume.

 

[creative_vision]

Put a PC/Laptop with REW installed next to the amp. Use another laptop at the listening position (or any other position) and remote desktop into the 1st machine. I usually measure my PC setup while being somewhere else with a laptop so I don't have to sit in the way, have no way of accidentially moving the microphone and I don't need to listen to the measurements at loud volume.

Thank you ... I get the idea in principle. So this is better than sending REW test tones etc via AirPlay to the Yamaha? Very keen not to over complicate things ... in line with @amirm approach that I read in his Room Measurement Tutorial for Dummies from 10 years ago!

If best way is indeed two laptop approach, am I right in understanding as follows:

- MacBook1 has REW installed and HDMI cable into Yamaha amp in an unused output
- MacBook2 has UMIK-1 attached and mirrors MacBook1 (hope I can work out how that's done!)

 

[Keith_W]

1. Do not use long USB cables to connect your laptop to your measurement mic. See this thread - the OP's inconsistent measurement issues were eventually traced down to a long USB cable. It causes all sorts of timing problems.

2. I do not recommend using two laptops connected with a remote desktop (presumably one laptop is connected to the microphone and the second laptop runs REW). The latency jitter will make all timing measurements impossible to interpret.

3. A better solution is to use a REW offline measurement. Make sure you include the timing chirp when you generate your sweep.

4. Check out the REW eBook in my sig.

 

[creative_vision]

1. Do not use long USB cables to connect your laptop to your measurement mic. See this thread - the OP's inconsistent measurement issues were eventually traced down to a long USB cable. It causes all sorts of timing problems.

2. I do not recommend using two laptops connected with a remote desktop (presumably one laptop is connected to the microphone and the second laptop runs REW). The latency jitter will make all timing measurements impossible to interpret.

3. A better solution is to use a REW offline measurement. Make sure you include the timing chirp when you generate your sweep.

4. Check out the REW eBook in my sig.

This sounds like a very elegant solution - thank you, reading your eBook now!

 

[creative_vision]

@Keith_W thanks for the eBook recommendation (and actually writing it!) ... really helpful for a newbie like me.

I think I understand the measurement process now, but my key question is what actually happens at the end of it?

My understanding of the process so far (especially in my setup above):

• Generate offline sweep files in REW and save to USB
• Play the offline sweep files from USB directly into the Yamaha in the utility room, while REW on MacBook with UMIK-1 captures the results in the cinema room
• End up with a set of frequency response graphs

But then what? How do I actually translate those graphs into real improvements on my system?

1. Does REW suggest specific EQ corrections I can apply, or do I have to interpret the graphs myself?
2. My Yamaha has a manual Parametric EQ with Band, Frequency, Q and Gain fields for each speaker (7 bands per speaker, but only 4 bands for subwoofers). Can I just type REW's suggested corrections directly into those fields?
3. How many correction bands would I realistically need for a setup like mine?

Also all my speakers are fixed in-wall so placement adjustments aren't an option. My two subwoofers have very limited placement flexibility too due to room furniture. So I'm really only looking at EQ corrections rather than physical optimisation.

Is this whole process still worthwhile given those constraints?

Thanks again!

 

[Keith_W]

The purpose of that REW book is to help you understand what the measurements mean and help you spot weaknesses that may need improvement. All REW and my book gives you is information. What you choose to do with that knowledge ... well, that is a huge can of worms. Maybe you need DSP. Maybe room treatment. Maybe more subwoofers. Maybe you need to rethink your system and where you arrange things. Nobody knows until you have the measurements in front of you. And the fact is, nobody cares about your system more than you do. Not even professionals whom you pay for their time. So if you want the best, you have to arm yourself with knowledge.

To answer your questions:

1. REW will generate PEQ's for you, but you have to set limits for what to correct and what to leave alone.
2. If your AVR is not directly supported by REW, then you will have to enter the PEQ's manually.
3. Nobody knows. It depends on many variables, e.g. how bad your measurements are, how many seating positions you wish to correct for, etc.
4. Is the process worthwhile? It's up to you. Do you think that learning about your system's deficiencies so that you can identify areas of improvement to be worthwhile? If you are happy with the sound the way it is, and feel no need to improve, I would stop right there.

 

[creative_vision]

The purpose of that REW book is to help you understand what the measurements mean and help you spot weaknesses that may need improvement. All REW and my book gives you is information. What you choose to do with that knowledge ... well, that is a huge can of worms. Maybe you need DSP. Maybe room treatment. Maybe more subwoofers. Maybe you need to rethink your system and where you arrange things. Nobody knows until you have the measurements in front of you. And the fact is, nobody cares about your system more than you do. Not even professionals whom you pay for their time. So if you want the best, you have to arm yourself with knowledge.

To answer your questions:

1. REW will generate PEQ's for you, but you have to set limits for what to correct and what to leave alone.
2. If your AVR is not directly supported by REW, then you will have to enter the PEQ's manually.
3. Nobody knows. It depends on many variables, e.g. how bad your measurements are, how many seating positions you wish to correct for, etc.
4. Is the process worthwhile? It's up to you. Do you think that learning about your system's deficiencies so that you can identify areas of improvement to be worthwhile? If you are happy with the sound the way it is, and feel no need to improve, I would stop right there.

@Keith_W thank you, that's a really helpful and honest framing and I appreciate you taking the time!

Your point about nobody caring more about my system than me really resonated. That's exactly why I'm here trying to learn rather than just living with it.

I think I now understand the REW process much better. My read of it is this: REW gives me an accurate diagnosis (if run properly in line with your eBook tips!), but the prescription could range from "easy DSP fixes" all the way to "you need new equipment and acoustic treatment." And I won't know which until I actually do the measurements.

The reason I'm genuinely hopeful that DSP alone might make a meaningful difference in my case is this: my system was installed roughly 10 years ago by what I'd describe as a somewhat rushed AV installer. He ran the Yamaha YPAO auto-calibration using what I now know was approximately a 15m extension cable on the YPAO mic ... which is apparently against Yamaha's own recommendation of no more than 5m. So the baseline calibration was almost certainly compromised from day one.

So there's at least a reasonable basis for optimism that correct calibration via REW could make a material difference, without needing hardware changes or room treatment.

What makes me think this is worth pursuing is a slightly embarrassing admission: my considerably cheaper Sonos Playbar and Sonos Sub (both the original launch versions) in our casual TV lounge honestly sounds more cohesive and impressive than this 7.2 Atmos cinema room setup. For context, the cinema room audio elements represent a total investment of roughly £8,000 versus around £1,500 for the Sonos setup. Appreciate many (including those on this forum) will be used to much higher end stuff, but to me as a novice, I just feel that the performance gap from £1.5k Sonos set up to the £8k 7.2 Atmos cinema room setup feels unreasonable and is worth investigating properly. I know the Sonos benefits from being factory-engineered as a matched system with automatic room calibration baked in (and I appreciate the rooms, sizes, shapes and furniture are all completely different variables) but it does make me wonder what properly calibrated versions of my Monitor Audio and B&W speaker set up might actually sound like. The speakers in the cinema room are installed in the textbook 7.2 arrangement (other than the subs) in a straightforward rectangle shaped room, so no funnies there.

That's what's driving me here. I'm not chasing perfection, I just want to hear what this system is actually capable of.

 

[Ruediger]

So I can't easily connect a laptop directly to the receiver unless I use really long cables, which I believe - but correct me if I'm wrong - is not ideal?

I recommend getting a 15m 3.5mm TRS cable and a trs2rca adapter cable at amazon. Plug that to line-in and laptop line-out. Cheap solution.

It's OK as long as there is no audible interference.

I also used 2 x 3m usb extender cables with the Umik-1. It should work with high lengths too.

 

[digitalfrost]

2. I do not recommend using two laptops connected with a remote desktop (presumably one laptop is connected to the microphone and the second laptop runs REW). The latency jitter will make all timing measurements impossible to interpret.

This is not what I was impying you just use the 2nd machine to remotely control the 1st machine which is directly connected to the audio devices and runs REW...

 

[Keith_W]

This is not what I was impying you just use the 2nd machine to remotely control the 1st machine which is directly connected to the audio devices and runs REW...

And where is the mic connected to? The 2nd laptop which is connected to the audio devices which is running REW, or the laptop which is used to control the first laptop?

 

[digitalfrost]

And where is the mic connected to? The 2nd laptop which is connected to the audio devices which is running REW, or the laptop which is used to control the first laptop?

I'd connect the mic to the laptop connected to the audio devices, 15m XLR cable should not be a problem?!

 

[creative_vision]

And where is the mic connected to? The 2nd laptop which is connected to the audio devices which is running REW, or the laptop which is used to control the first laptop?

Pretty sure it was my unusual setup plus a skim read that had @digitalfrost mention two laptops ... but of course the mic has to live in the cinema room, and with normal cable lengths there's no realistic way to hook the same laptop up to the AVR in the other room without running into latency/interference issues.

Anyway, give the guy a break @Keith_W lol ... I'm the actual novice here (in case that wasn't already obvious from my earlier posts ), and I genuinely appreciate all the help I can get. My setup is a bit unusual compared to what most DIYers deal with, and all I was really hoping to do was spend 3–4 hours tinkering with this borrowed UMIK-1 to see if I can get something at least a bit better than the Sonos setup in our other room - given the cost differential between the two!

 

[creative_vision]

I'd connect the mic to the laptop connected to the audio devices, 15m XLR cable should not be a problem?!

15m XLR cable?
So I can just use one laptop sitting next to the AVR, with the mic running from it all the way back to cinema room ... great if that works!

On which note, then why not bin REW (given how novice I am) and just use the Yamaha's own YPAO auto-calibration system with an appropriate cable extension for their mic (which comes with 5m as standard) Or am I going down a rabbit hole ...

 

[Ruediger]

With Win Pro you can remote use another PC on your network with RDP. And set that connection to let/run all devices on the remote PC. Incl. sound devices. So you only get screen, keyboard, mouse. That should work OK for REW, the GUI could be bit slower though.

Same with any of the VNC solutions for PC.

As you have a Yamaha 1060 I recommend to do YPAO first. So you have a set of measurements in the AVR and can start to use the linear-natural-front variations of it. The microphone cable can be extended if needed, but I think YPAO has a distance limit in itself (not sure about values). YPAO isn't bad at all. You will have good starting points to use right away.

 

[Keith_W]

I'd connect the mic to the laptop connected to the audio devices, 15m XLR cable should not be a problem?!

Agree, a 15m XLR cable won't be a problem. I thought you had a USB cable in mind - I gave a link to this thread on AVNirvana where someone posted a bunch of measurements that left me utterly confused. It's rare that I need to ask John Mulcahy for help, but I genuinely could not figure that one out. So it stuck in my mind a bit

 

[Keith_W]

Anyway, give the guy a break @Keith_W

And just to be clear, it was not my intention to be hard on him. I was asking him to clarify what he had in mind. If I came across as being harsh, please accept my apologies @digitalfrost

 

[Sokel]

About offline measurements, @Ageve has you covered:

Help with REW on MacBook

Hi all I’m trying to run a measurement on REW So I have connected umik up..I understand this will be the input..I’m using a MacBook Pro to run REW..obviously when REW try’s to run the test tone to measure the output is through the MacBook. Will I need to buy a usb c cable to connect MacBook...

www.audiosciencereview.com

 

[Ageve]

About offline measurements, @Ageve has you covered:

Help with REW on MacBook

Hi all I’m trying to run a measurement on REW So I have connected umik up..I understand this will be the input..I’m using a MacBook Pro to run REW..obviously when REW try’s to run the test tone to measure the output is through the MacBook. Will I need to buy a usb c cable to connect MacBook...

www.audiosciencereview.com

1. Generate a measurement sweep in REW (Tools, Generator). If you use the settings below, you will get a 5.5s sweep in both channels, with a timing reference in the left channel.

2. In the measurement window, click on "From file", and browse to the generated sweep (blue folder). Make sure that the calibration file for your UMIK-1 is loaded, and click start. REW will now start listening for the first timing reference (a short "chirp" at the beginning of the generated file).

3. Play the generated file from any lossless source (USB-stick in receiver, AppleTV or similar). When REW detects the first chirp, it will start recording, and then stop after the second one.

If you get weird results, make sure that no SRC (sample rate conversion) is applied. On your MAC, go to Audio/MIDI-setup (search for MIDI), and make sure that your UMIK-1 is set to 48 kHz sample rate (if you're using the sweep settings above), and also make sure that the playback device isn't resampling to 44.1 kHz.

Use the simplest/most reliable method for playback (I would avoid AirPlay, and definitely not use Bluetooth).

Also avoid using a long USB cable. With UMIK-1 you could get inconsistent measurements. UMIK-2 is more reliable (using a better USB standard, and has an internal clock), but it could still loose connection.

 

[creative_vision]

1. Generate a measurement sweep in REW (Tools, Generator). If you use the settings below, you will get a 5.5s sweep in both channels, with a timing reference in the left channel.

View attachment 532833

2. In the measurement window, click on "From file", and browse to the generated sweep (blue folder). Make sure that the calibration file for your UMIK-1 is loaded, and click start. REW will now start listening for the first timing reference (a short "chirp" at the beginning of the generated file).

View attachment 532834

3. Play the generated file from any lossless source (USB-stick in receiver, AppleTV or similar). When REW detects the first chirp, it will start recording, and then stop after the second one.

If you get weird results, make sure that no SRC (sample rate conversion) is applied. On your MAC, go to Audio/MIDI-setup (search for MIDI), and make sure that your UMIK-1 is set to 48 kHz sample rate (if you're using the sweep settings above), and also make sure that the playback device isn't resampling to 44.1 kHz.

Use the simplest/most reliable method for playback (I would avoid AirPlay, and definitely not use Bluetooth).

Also avoid using a long USB cable. With UMIK-1 you could get inconsistent measurements. UMIK-2 is more reliable (using a better USB standard, and has an internal clock), but it could still loose connection.

Brilliant - thank you ... but a question ... in the Channels dropdown I see no option for 7.2. I assume because I'm generating this offline on my MacBook Pro which naturally just has two channels. But do I not need to generate a sweep file for 7.2 to load into my Yamaha? And if so, how to do that?