When I was considering acoustically treating my office/listening room/recording room I couldn’t find a lot of “pre vs post” room reverb measurements online, so I wanted to share my data below to contribute to the collective knowledge-base.
The room:
Approximately 12x12x8ft. Hardwood floors with no rug or carpet. Walls/ceiling drywall. Main plush furniture is a big loveseat and an ottoman. There is always a lot of stuff in the office (guitars, gear, storage) but not a lot of absorptive materials. In both sets of measurements I was in the room so would contribute slightly to absorption also.
The speakers:
DIY active monitors using Adire Extremis 6.8 (anyone else remember this?!?) and a Peerless 810921 (now ScanSpeak D2608) tweeter in the dome SEOS waveguide using MiniDSP Flex for crossover. Ported box and gets down to ~50hz before rolling off. Note for anyone who tries to replicate the waveguide setup, the faceplate isn’t flat and the resulting gap created a resonance, so I used Sugru to mold a flat/smooth mating surface.
The treatment:
Why did I do this / my expectations:
I’ve been an audio enthusiast for >25 years, building my own gear etc, but have never tried acoustic treatment. It’s a new frontier – would it do anything I could measure? Could hear? Frankly for how much I was willing to put on my walls (not much) I didn’t expect anything – was definitely primed for disappointment.
Pre vs. post measurements:
Subjective assessment: As mentioned above, I was expecting no discernible change. To my surprise there was quite a change. It is very hard to describe – but everything seemed more “dry” (e.g. less reverb), focused (imaging more precise), and for lack of a way to describe it, precise. More headphone-like, perhaps. I know my speakers have very low distortion from measuring them, but this felt like a “different” kind of distortion was taken away. I can now more easily hear effects applied in a mix (ok I see it sounds like the track was doubled, phaser added, etc.) whereas before I would just hear the “sound” and be unable to pick it apart. A voice which before sounded like it came from a cantelope-sized space now almost seems to come from a tiny point.
So I love it right? Well…probably I’m just used to listening in reverberant and untreated spaces, but the short answer is no – I actually enjoyed listening to music more before. If I was an audio mixing professional, I 100% would prefer the treated setup as it would make hearing effects, understanding reference tracks, etc much easier. But I listen to music for fun/pleasure and it has taken some of the fun/emotional connection away.
I’m planning to leave it – I figure it may grow on me and there are other practical benefits (absorbs my loud guitar playing etc.). Would I recommend this as an experiment for learning? Yes of course if your budget allows. Would I recommend this for enjoyment/optimization especially if budget is tight? I would recommend you go listen to a good audio setup in a more professionally damped space and see if you like it.
Hopefully the above helps the community! I have a very full life (3x small kids etc.) but if there are comments or questions I will do my best to respond with delay.
Bonus: Since this is ASR here is the distortion plot and FR at ~80db 8 samples - that tweeter has some seriously low distortion!
Yeah I know, its not that flat etc etc I still like it
.
The room:
Approximately 12x12x8ft. Hardwood floors with no rug or carpet. Walls/ceiling drywall. Main plush furniture is a big loveseat and an ottoman. There is always a lot of stuff in the office (guitars, gear, storage) but not a lot of absorptive materials. In both sets of measurements I was in the room so would contribute slightly to absorption also.
The speakers:
DIY active monitors using Adire Extremis 6.8 (anyone else remember this?!?) and a Peerless 810921 (now ScanSpeak D2608) tweeter in the dome SEOS waveguide using MiniDSP Flex for crossover. Ported box and gets down to ~50hz before rolling off. Note for anyone who tries to replicate the waveguide setup, the faceplate isn’t flat and the resulting gap created a resonance, so I used Sugru to mold a flat/smooth mating surface.
The treatment:
- 2x GIK B4 full range 2ft x 4ft traps on the wall right behind the monitors, Guilford cloth
- 3x 2x3 Audimute ~1.5” panels up higher on the wall behind listening area and on side wall, Guilford cloth
- Why mix/match? The 4” B4s are pretty beefy, and the thinner panels just look better hanging on the wall up high.
- I made sure the B4s could effectively absorb the main first destructive back-wall reflection from the monitors – otherwise would have gone for 244 (from memory I think this was ~170hz or so – around there)
- The room is generally quite messy so I’m not going to include a photo, but the desk with monitors is against the wall and off-center to be nearer to a window. This puts the left monitor almost in a corner, so then the left B4 trap is also then in a corner. B4 traps set up to start ~6in off the ground and all 5x panels are mounted flush to wall.
Why did I do this / my expectations:
I’ve been an audio enthusiast for >25 years, building my own gear etc, but have never tried acoustic treatment. It’s a new frontier – would it do anything I could measure? Could hear? Frankly for how much I was willing to put on my walls (not much) I didn’t expect anything – was definitely primed for disappointment.
Pre vs. post measurements:
- Measurement method:
- Behringer ECM8000 omni measurement mic into Focusrite Scarlett 2nd gen 18I20. Mic placed at ear height at listening location (~4ft from each speaker on axis with tweeter). 8 samples used at ~80db. Single speaker used and same speaker used in pre vs post measurement (left speaker – the one in the corner). Given low noise floor of my house, this provided a lot of room for measuring decay before hitting noise floor.
- There is a sliding glass closet – the door was closed for these measurements and the office door was always closed and the AC off.
- I was in the room for consistency but sitting on the floor quietly away from the mic.
- Its worth noting that EQ was applied to the speaker/resonances fixed with PEQs before listening/measuring in both cases. As far as I’m aware this EQ should not have changed the reverb measurements.
- RT60: In general it went from 400-450ms to ~300ms from ~300hz up; Bass region a bit messier but especially in midbass much lower in treated scenario
- “Pre” results, RT60 Topt:
-
- “Post-treatment” results, RT60 Topt
- Clarity: This one I can’t begin to say what is good or bad but here are the #s – for C50-C80 treatment seems to have increased the values 3-5db on average:
- Pre-treatment:
- Post-treatment:
Subjective assessment: As mentioned above, I was expecting no discernible change. To my surprise there was quite a change. It is very hard to describe – but everything seemed more “dry” (e.g. less reverb), focused (imaging more precise), and for lack of a way to describe it, precise. More headphone-like, perhaps. I know my speakers have very low distortion from measuring them, but this felt like a “different” kind of distortion was taken away. I can now more easily hear effects applied in a mix (ok I see it sounds like the track was doubled, phaser added, etc.) whereas before I would just hear the “sound” and be unable to pick it apart. A voice which before sounded like it came from a cantelope-sized space now almost seems to come from a tiny point.
So I love it right? Well…probably I’m just used to listening in reverberant and untreated spaces, but the short answer is no – I actually enjoyed listening to music more before. If I was an audio mixing professional, I 100% would prefer the treated setup as it would make hearing effects, understanding reference tracks, etc much easier. But I listen to music for fun/pleasure and it has taken some of the fun/emotional connection away.
I’m planning to leave it – I figure it may grow on me and there are other practical benefits (absorbs my loud guitar playing etc.). Would I recommend this as an experiment for learning? Yes of course if your budget allows. Would I recommend this for enjoyment/optimization especially if budget is tight? I would recommend you go listen to a good audio setup in a more professionally damped space and see if you like it.
Hopefully the above helps the community! I have a very full life (3x small kids etc.) but if there are comments or questions I will do my best to respond with delay.
Bonus: Since this is ASR here is the distortion plot and FR at ~80db 8 samples - that tweeter has some seriously low distortion!
Yeah I know, its not that flat etc etc I still like it
.
