Nyal Mellor

[dallasjustice]

For some of you that don't Nyal, you should know him. Nyal is an acoustician. His mission in life is to improve the sound in your listening room using real measurement tools and real acoustics knowledge. I built an addition onto my house. Nyal did not design my listening room. I did the best I could under the circumstances. My room is 14'6"x24'x9'3", 5/8" soundboard over standard wall studs and a double wood floor with green glue in between (nothing special for sure). I knew I would need room treatments. I didn't know where to begin. I discovered the XTZ room analyzer and that's how I met Nyal, by phone. Nyal showed me how to use it. He really didn't have to because it's so easy to use, but I have been down the DRC road before and had been sorely disappointed.

Where do the speakers go?! I pushed them around alot before I met Nyal. I wasn't using any measurement gear. The first measurements taken with XTZ showed that the most dominate room mode was centered at 47Hz @12.5db. Nyal advised me that room treatments would touch it and if I didn't want another set of subs in the rear of the room to cancel this mode, I would need to find the null for this room mode. Nyal showed me how to do this simply using the mic and the RTA function in XTZ. I found the null almost exactly where Nyal predicted it would be; 5'2" from the front wall.
Here's bass response before Nyal:


Nyal came up with a room treatment design and I implemented it with the help of my dealer Scotty Warren and my other friend Bill Gainer. Here's are some photos of my room:


After the treatments were setup and I dialed in the toe-in (3/8"), I was ready for parametric EQ. This is the part where most audiophiles will go running for the door. Although Nyal is a proponent of EQ, he does not think EQ can solve all problems. At this point my decay time was about .4 seconds evenly across the frequency spectrum. I was told that my room would sound dead and "uninvolving" with all of these treatments. I don't hear it. The decay time is perfect for me. I am not a live music re-creator. I simply want the musical performance as it was originally recorded.

How to EQ? As you can see, I only use a music server for my source. I have a custom windows music server. I run Jriver is media server mode. Jriver is the best software I have tried and I have tried them all on mac and windows, almost. Nyal recommended a VST plugin called FabFilter. It's very easy to use. Nyal and I ran one more XTZ measurement and then Nyal recommended a total of 6 bands of parametric EQ (all low frequency). XTZ has a simulation mode so I was able to test his recommendations out and this is what the result was:



Fabfilter is totally transparent. I can turn it on and off and I lose nothing in the higher frequencies. The only difference that can be heard is the corrected frequencies. Here's a screeshot of the fabfilter plugin for Jriver:


All of the work Nyal did was remote. Nyal takes a teaching approach to his work. I learned a lot during this process and I feel much more comfortable with things like room treatments and EQ than I used to feel. Thank you Nyal! My system is no longer there. I can close my eyes and the music just flows from another dimension.

[flez007]

I am a firm beleiver of room treatment, and taking the professional route is the way to go IMHO, not sure but looks to me I have read from Nyal somewhere eles in this same forum. (nice system/setup BTW).

[MrAcoustat]

I also am a believer in room treatment BUT in a dedicated room, if all you have is a living room then you have to work with what you have and a livingroom is not a recording studio you may have very good intentions but life is life always remember that there are many audiophiles that would be very happy with what you have.

PS: Not the best set up, but i have seen worst, be happy whith what you have.

Attachment 3805

[Nyal Mellor]

First off, thanks for the great writeup and photos! It was great working with you on your listening room

For those of you that are interested all the treatments used in the room are from Primacoustic. They are a relatively new onto the acoustics scene and are based in Canada. Their treatment is extremely effective from an acoustical perspective, reasonably priced and they have quite a wide range of products including diffusers, absorbers and bass traps. They also keep everything in stock which is the opposite of most acoustics companies who make everything to order. Whilst RPG is my premium acoustic treatment line, since their products are awesome and available in a ton of fabric wraps and finishes, their lead time is like that of a fine furniture company. In this case the OP wanted to get his room treated ASAP, which meant Primacoustic was perfect.

We used Primacoustic MaxTraps, FullTraps, 3" Control Columns, FlexiFusers , Razorblades and Stratus.

The MaxTraps were double stacked in all room corners, the FullTraps on the front wall to reduce the speaker boundary interference caused by the superposition of the direct sound from the speaker and the reflected sound from the back wall.

The FlexiFusers were used at the first reflection points on the sidewalls and the Razorblade at the first reflection point on the back wall. I would have liked to use more Razorblades but there was an errant light switch in the way which prevented us from doing so. The great thing about the FlexiFusers is that they have these 'vanes' that you can adjust to change the balance of reflected vs direct sound. Since the side wall is such an important location for soundstaging and imaging this allows each person to adjust things to their preference. More absorption = more focused soundstage, less absorption = wider soundstage. If the speakers are well enough behaved off axis (which these ones are, as we validated through analysis of the spectral decay of the mid and high frequencies in the room), then you are free to do what you want subjectively with the side walls.

The Stratus are hung in a cloud to absorb the first ceiling reflection point (I have not yet measured a multiway speaker that has good enough vertical off axis performance to warrant use of a diffuser) and the Control Columns were specced to remove the side to side flutter echo across the listening position and provide additional decay time reduction.

Considering that there are no separate subs in this system the bass response we ended up with is extremely flat. Obviously the EQ helped quite a bit here, and I am a firm believer in using it below 100Hz, especially for two channel listening where there is only one sweet spot. For home theaters with multiple seats you first have to get seat to seat variability as low as possible with multiple subs and careful seat positioning before applying EQ if it is to be as effective.

I have some graphs to post but those will have to wait until later as it is BBQ time!

[dallasjustice]

Before my wife kicked me out of the living room I had really nice bass with minimal treatments. Your setup looks alot cleaner than mine was in the living room.

The hardest part in my dedicated room is bass. Everything above 200hz is flat and RT is pretty flat across the board at around .4 seconds.

[dallasjustice]

It's nice to have subs with alot of controls. I made a couple of adjustments and here's my new corrected bass response:


also, here's a screenshot of fabfilter EQ settings:

[NorthStar]

-----Very impressive, thx for sharing.

[Bruce B]

also, here's a screenshot of fabfilter EQ settings:

Just my personal opinion, but I would never use additive EQ and only subtractive EQ at <3dB.

Graphs look great though.

[dallasjustice]

Just my personal opinion, but I would never use additive EQ and only subtractive EQ at <3dB.

Graphs look great though.

Bruce, I found this thing called a volume knob on my plate amps. I re-ran my measurements with said volume turned up slightly. You are correct. It is better to give than receive. :-) Here's the new measurement:

and my new EQ settings; no need to add any gain into EQ now:

[Peter Breuninger]

Nice looking system. How long have you been a BMC'er?