Post Your Frequency Response Curve!

It has been suggested to me that the real time analyzer software I am using is not dependable. I am prepared to download and use Room EQ Wizard.

The only glitch is that my computer stuff is 100% Apple focused. so I guess I have to buy a PC laptop or a PC tablet just to use the free REW.

In the experience of our REW users is it easier to use REW on a PC laptop or a PC tablet, or it just doesn't matter?
 
Also I have my high class, very flat frequency response Earthworks QTC40 microphone. I have a power supply to provide phantom power to that microphone, but I now realize that I need an external preamp as well.

So I might start over there too and just order UMIK-1 or UMIM-2 with calibration file.

Any thoughts on these microphone options?
 
Also I have my high class, very flat frequency response Earthworks QTC40 microphone. I have a power supply to provide phantom power to that microphone, but I now realize that I need an external preamp as well.

So I might start over there too and just order UMIK-1 or UMIM-2 with calibration file.

Any thoughts on these microphone options?
Ron, unless you’re doing JA type measurements, IMO a UMIK-1 (get the 1, not the 2, there’s stuff online describing why - although either will work fine really) with a cal file is sufficient for REW and room measurements.
 
Ron, unless you’re doing JA type measurements, IMO a UMIK-1 (get the 1, not the 2, there’s stuff online describing why - although either will work fine really) with a cal file is sufficient for REW and room measurements.

Thank you!

I see that an Apple laptop with a current version of OS will run REW. So I might have to get a new Apple laptop just for REW just to stay in the Apple ecosystem.
 
Thank you! I ordered a UMIK-1 and a cheap, lightweight boom mic stand. (The high quality tripods that I use for my video camera are a little heavy and unwieldy for this purpose, I think.)

I was able to download REW on my early 2015 Apple laptop.
 
Last edited:
I see that an Apple laptop with a current version of OS will run REW. So I might have to get a new Apple laptop just for REW just to stay in the Apple ecosystem.
Yes. I use my M1 MacBook Pro for REW.

But my take often is that we shouldn't have to buy new gear if our current ones work.

Maybe if you can tell us what MacBook and which iPad you currently have, we can find a better software alternative for you.

I have to admit, for most simple things, my dealer and I just use the iPad and AudioTools. Only for the really complicated sophisticated measurements would I resort to REW with the MacBook Pro.
 
Thank you! I ordered a UMIK-1 and a cheap, lightweight boom mic stand. (The high quality tripods that I use for my video camera are a little heavy and unwieldy for this purpose, I think.)

Now I have to get a basic Apple laptop, I guess.
Get a used Behringer DEQ 24/96 and calibrated mic from Behringer. Cheap, accurate and no computer needed. Not highest resolution but 1/6th octave is really good enough for most purposes. It’s what I use and it’s quick and easy to setup. You also use the EQs for bass mode reduction at least to see the effects of removal.
 
Get a used Behringer DEQ 24/96 and calibrated mic from Behringer. Cheap, accurate and no computer needed. Not highest resolution but 1/6th octave is really good enough for most purposes. It’s what I use and it’s quick and easy to setup. You also use the EQs for bass mode reduction at least to see the effects of removal.
Thanks, but I'm tired of futzing around and getting results. I want to do it in an industry standard (at least for nonprofessionals) way this time.

I'll bite the bullet and learn to use REW.
 
  • Like
Reactions: ecwl
Does anyone consider to remove one set of speakers in the room first ?
there both not little box speakers
I get possible why Ron don’t and why he tried his other woofer towers
Ron asks honest questions and as who he is many try to help
but most all tip toe around the obvious
taking measurements is needed but like most things in this hobby
unless your are able to understand what’s shown and the many methods to achieve them
It’s a shit show in the dark
I’m sure Ron is aggravated for asking by now hahaha
and im tapping out on this topic
 
If you have a microphone calibration file like all UMIK microphones provide, that's all you need to get an accurate measurement.

FWIW, this is my latest listening position response plot.

Untitled-1.jpg
 
  • Like
Reactions: ecwl
Thanks, but I'm tired of futzing around and getting results. I want to do it in an industry standard (at least for nonprofessionals) way this time.

I'll bite the bullet and learn to use REW.
Good for you, Ron. There’s a bunch of us here who’ve used REW for year. Help is always around if needed, and John Mulcahy has a dedicated forum on AVNirvana.
 
  • Like
Reactions: Alrainbow
Also I have my high class, very flat frequency response Earthworks QTC40 microphone. I have a power supply to provide phantom power to that microphone, but I now realize that I need an external preamp as well.

So I might start over there too and just order UMIK-1 or UMIM-2 with calibration file.

Any thoughts on these microphone options?
That’s a solid response test mic. Don’t forget to take a lot of samples in various positions close to your listening spot. Then average the plots.
 
A few weeks ago I went down the same REW rabbit hole, Ron. MacBook Pro and Umik mic calibrated are ok. I use 1/12 smooth and you will find Spectrogram and waterfall graphs usefule.

Enjoy!

Here’s my results comparing 3 different bass traps placements last week (sorry for different scale, I’m on iPad now, need to take new pics to uniform different views)
L+R.jpeg

Here where I started 3 months ago:
L+R.jpeg
 
  • Like
Reactions: ecwl
It has been suggested to me that the real time analyzer software I am using is not dependable.
Hi Ron,

if you are looking for dependablity, a microphone with a microphone preamp is better.

With USB microphones, there can be a drift in the timing. This is because they have their own ADC (analogue-to-digital converter). This means that two independent clocks are used for playback and recording. This usually leads to sub-optimal measurement results because the pulse responses exhibit time stretching/compression effects. This is because the synchronisation of these two clocks is very important for a pulse measurement that also takes the time domain into account. The first clock is located in the DSP and generates a log sweep with a precisely defined sample rate. E.g. 48,000 samples per second. The clock in the USB micro, for example, is slightly slower and has 48,001 samples per second in the same period. With a 60-second sweep, that's already a difference of 60 samples in length! There is something like clock drift correction in room correction programmes. But you have to measure and calculate this drift first.

An analogue microphone with a microphone preamplifier avoids all these problems. Because there is only one clock, namely the one in the USB audio interface. An inexpensive and good DAW is for example UR12 | Steinberg

GA-Steinberg-UR12-1.png


This would be the measurement setup:

Topo-Measurements.png

Source: How to measure your room and speakers – Grigg Audio Solutions

Warmest regards

Gabriel
 
Last edited:
A few weeks ago I went down the same REW rabbit hole, Ron. MacBook Pro and Umik mic calibrated are ok. I use 1/12 smooth and you will find Spectrogram and waterfall graphs usefule.

Enjoy!

Here’s my results comparing 3 different bass traps placements last week (sorry for different scale, I’m on iPad now, need to take new pics to uniform different views)
View attachment 131853

Here where I started 3 months ago:
View attachment 131858

Is this measured in the listening position? Looks pretty light on bass?
 
  • Like
Reactions: luca.pelliccioli
Is this measured in the listening position? Looks pretty light on bass?
Don’t know what I made wrong, my bad! This is the last measurement from listening position.

With and without a bass trap on the right corner.

left right.jpeg

The room is 12x18x8 - here below a recent pic
IMG_1080.jpeg
 
  • Like
Reactions: sigbergaudio
Thank you!

I see that an Apple laptop with a current version of OS will run REW. So I might have to get a new Apple laptop just for REW just to stay in the Apple ecosystem.
I run REW on an ancient Macbook that we bought my son in Grade 7. He's three years out of undergrad so it's about 12 years old. FWIW, I recently had an acoustics consultant in who used a Dayton real-time analyzer that was incredibly useful when integrating my subs (which have DSP). Being able to see the changes on the screen as they are made is very effective and efficient.
 
I was inspired by this thread to order a Umik1 and download REW to measure front left and right speakers. I am still tweaking REL no 25s. But music sounds better than ever. Microphone and sitting position is ~13ft from speakers.
 

Attachments

  • Screenshot 2024-07-21 180043.png
    Screenshot 2024-07-21 180043.png
    87.1 KB · Views: 32
I was inspired by this thread to order a Umik1 and download REW to measure front left and right speakers. I am still tweaking REL no 25s. But music sounds better than ever. Microphone and sitting position is ~13ft from speakers.
Good work!
 
With over 1000 systems voiced, I have never found that final dependence on excellent measurements will enhance Musical Engagement. In fact, more often than not, searching for the best measurements can bring the listening experience to focusing on sounds, rather than falling into the music.

I am not speaking against employing good measurements on the path to enhanced Musical Engagement. Just be careful that you don't think you are done solely by getting better measurements.

Certainly, good measurements are an excellent reference point, but not necessarily the final achievement to be sought after, IMO.
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu