Nick Barnett's Recording Studio Monitors

[stryke]

How does it fare having the left side crawling down the wall and the other one unloaded? Do you have any L/R bias from the wall?

What power amplifiers/processing are you using?

They look badass!

Is Nick a musician?

Chad

Well with the wonders of DSP Mark was able to match the two channels quite well. The amplifiers from SpeakerPower have all the DSP built in.

Nick does a lot of hiphop stuff. I heard some pretty good tracks he was working on over there.

John

[Mark_Seaton]

How does it fare having the left side crawling down the wall and the other one unloaded? Do you have any L/R bias from the wall?

What power amplifiers/processing are you using?

They look badass!

Is Nick a musician?

Chad

Hi Chad and others reading along,

Even through a lot of hurdles to figure out, this turned out a killer end result, and most importantly, John told me Nick was very impressed with the end result.

Fortunately John was able to get in and take care of the side walls acoustically. There is 6" of absorption behind the fabric you see on the walls. Being slightly off-center is both good and bad. It tends to help reduce deep nulls in the upper bass response, but you then have to work a little harder to keep the left-right balance. The 13-15 deg angle inward on the 8" coaxial combined with its HF directivity left the upper frequency range very well matched between the channels from the start. The differences and room-related issues were mostly as we expected, below ~800Hz and above about 40Hz.

I know many were looking for measurements. I took over 300 measurements while in Green Bay, and found that I don't have a ton of "marketing quality" measurements as in-room you can't really measure full range with appropriate resolution or windowing. I do have a few good captures of some important qualitites though. Let's start with a 100Hz - 21kHz measurement taken at AE's shop while getting the crossovers and responses gellin' before we put them in the confines of the small room. Obviously there are some issues that come into play as the baffling is different in-room vs. what we were able to easily mock up, but with a baffle this wide, the midrange up was operating into 1/2 space.

Here is what many on the web like to show you, with ~1/3rd octave smoothing. This view is good to see general trends and is a good step back and check of what is going on:


Here is a look at the same measurement with 1/6th octave smoothing, which is pretty close to our upper frequency hearing acuity:

[Mark_Seaton]

Of course we are all bass nuts here, so we want to get an idea of what happened when we dropped these in the room...

Here is a higher level sweep I took with both subs running from the listening position. Note that this was before any EQ. The rise above 30Hz are expected room modes. What was nice is that we had no dramatic nulls to deal with. What is even more impressive is that being a studio with un-filtered mics getting routed to the speakers, I inserted a 9Hz, 2nd order high-pass on the system to protect against any really absurd bumps. The roll off you see is from this filter. The response of the sealed subs as I had dialed them in at the shop worked just as planned with in-room response to below 10Hz. I have a later measurement post-EQ, but at a much lower level. This was starting to work the drivers and amp a bit, but there was still a good bit left in the tank.

[Mark_Seaton]

Here's a better look at what I did with some EQ to get the final result we ended up with. Note the scale and that the cursors show the response here fits +/-2.5dB at the listening position!

[Big Daddy]

Sorry to wander OT,

Mark, You were at SDL/Servodrive weren't you?

I'm from Champaign, worked at C.V. Lloydes for a long time (still do contract work) you may know the name. Also friends with Tim Vear of Shure and Mark Rubel of Pogo Studios (Tim's friend).

I MAY have even spoken with you on the phone regarding some servodrives and the blue/brown motor mystery

Chad

[Mark_Seaton]

Sorry to wander OT,

Mark, You were at SDL/Servodrive weren't you?

I'm from Champaign, worked at C.V. Lloydes for a long time (still do contract work) you may know the name. Also friends with Tim Vear of Shure and Mark Rubel of Pogo Studios (Tim's friend).

I MAY have even spoken with you on the phone regarding some servodrives and the blue/brown motor mystery

Chad

Hi Chad,

You are correct. I did my servitude to the audio industry at ServoDrive/Sound Physics Labs. I seem to recall a few conversations that were likely with you. Both Tom Danley & I finally got out of the operational mess at ServoDrive, and am now off on my own while still in contact and always looking at collaboration with Tom Danley, and of course you see here with John Janowitz whom I have known since I got into DIY speakers when we were both a bit more nieve.

You can see what I've been working on at my own forum:
Seaton Sound Discussion Forum

I've also been designing subwoofers for AV123 where you might recognize that John has provided some help on some prototypes there which are not yet in production.

[Big Daddy]

It's great to see you doing well, I'm out of touring/live now and at the UI School Of Music. Working for the man now Family life dictates tht I settle down.

Best of luck!

Chad