OK Guru's - I'm lost

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HT cOz

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Re: OK Guru's - I'm lost
« Reply #40 on: 27 Jan 2012, 02:06 am »
I got an acoustically transparent screen and treated the space behind the screen with Rockwool. 

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #41 on: 1 Feb 2012, 09:35 pm »
Decided to take the plunge and odered 2 pairs of AQD-1's from PI Audio and some OC703 from Acoustimac as starting points for real treatments. Figure it will be a couple of weeks before everything arrives and I can start messing around with that.
In the meantime, I figured I'd go ahead and take some measurements. Dug out my Radio Shack Digital sound meter and the Alan Parsons Soundcheck2 CD. Plan on checking after I install the OC703.

YUCK!!!!! Terrible measurements. ("Fast" "C")(by hand close to main listening position - tried to keep everything as steady as possible and used my best guess for the average of each level - they still fluctuate a bit at each frequency). I knew it would be bad given my room, but this is disappointing. I got lots of work ahead of me.

Dug out an old Creative Labs Soundblaster external soundcard - gotta figure out how to connect it, download REW to a laptop, and see if I can get something usable.

 :thumbdown: :thumbdown:

Cheeseboy

Re: OK Guru's - I'm lost
« Reply #42 on: 2 Feb 2012, 08:46 pm »
That's a great first step.  We all have to start somewhere.   I'm going to start directly behind the speaker.  Should I get measurements first or just go for it. 

There is no way I can get the back of the LS6 3 feet from the front wall. There are a whole bunch of ports back there.   If they are only 1.8 feet then what type of absorption should go behind them.  What Fequency and what kind of reduction in loudness?

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #43 on: 2 Feb 2012, 09:22 pm »
Wasn't quite sure I was gonna post this yet - I'd like to get some confirmation, but I'm reasonably confident in the new results.....

Went back to the basics of room nodes and the rules of 1/3, 1/5, 1/7, etc. Moved the speakers closer to the front wall so that the center of the face of the speaker is roughly 42.5" from the front wall - 1/5 of the length of the front to back (partial) wall. I'm now just under 10' from the front of the speakers and they are about 8' apart - roughly 3' from the side walls. Angled to cross right at the primary listening position. Remeasured.

This is the part I'm still waiting for confirmation on - how accurate is the RS Digital SPL meter?

I remembered there are issues, especially at low frequencies. I found a whole bunch of "correction" tables for the Analog version, so I'm not sure if the Digital is exactly the same.  :scratch:

This is the correction table I used: http://diyaudioprojects.com/Testeq/RadioShack_33-2050/33-2050.htm


Anyway, my frequency response for both channels using the AP Soundcheck2 CD is now +/- 3 db from 25 hz -over 8khz, and only down 5.5 at 20 Hz.  :thumb:


I seem to drop pretty bad starting at 8 kHz - too dead of a room?

Ah well, much happier with the measurements at any rate.


Imaging and focus good, Soundstage - Very wide and coherent (no obvious speaker location).

Depth?

 :thumbdown:

I will keep things as they are for now, add some OC703 2" in the corners behind the book cases and to a couple of other locations. AQD-1's in between the speakers on the front wall (with  OC703 just to the outside of that - potential front wall first reflection point), and some more OC703 on the first reflection point of the sloped cathedral ceiling.

I'll take more measurements after that and see what, if anything changes, and hope for improvements on the other things (DEPTH). Have to get a different soundcard if I want to try to use REW.

Danny Richie

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Re: OK Guru's - I'm lost
« Reply #44 on: 2 Feb 2012, 09:37 pm »
Don't forget that you have to do each speaker individually or the response will be all over the place.

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #45 on: 2 Feb 2012, 09:58 pm »
Don't forget that you have to do each speaker individually or the response will be all over the place.
Yeah - it does fluctuate a bit. Honestly, I'm a little sick of listening to frequency sweeps, squinting at the display, and writing down the numbers at this point :green:

I know from earlier testing that I have a much bigger mid-bass "suck out" on the right speaker for whatever reason. :scratch: (but I'll check again at some point to see what's changed)

mlbrand

Re: OK Guru's - I'm lost
« Reply #46 on: 3 Feb 2012, 04:17 am »
Yeah - it does fluctuate a bit. Honestly, I'm a little sick of listening to frequency sweeps, squinting at the display, and writing down the numbers at this point :green:

I know from earlier testing that I have a much bigger mid-bass "suck out" on the right speaker for whatever reason. :scratch: (but I'll check again at some point to see what's changed)

I've been there and done that, it's really tough doing manual measurements. Get the right soundcard to use REW, it's well worth it.

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #47 on: 3 Feb 2012, 05:25 am »
I've been there and done that, it's really tough doing manual measurements. Get the right soundcard to use REW, it's well worth it.
I want to do that, but there doesn't seem to be a clear concensus on which soundcard to get. I have one in my "shopping cart" at Amazon, but I'm still not convinced that it's a good choice. (Behringer U-Control UCA202 USB)
I'm running Windows 7 on the laptop I would be using. RS Digital SPL- don't think I want to buy something more expensive at this point, but........

Rclark

Re: OK Guru's - I'm lost
« Reply #48 on: 3 Feb 2012, 05:33 am »
I'll snipe this question in there since the right people are looking, do planars require a different measuring technique than box speakers?

To the OP look at the omnimic. Everything you need in one box. Better quality than a rat shack meter and no need of a fancy soundcard. That's what I'm doing. Its at partsexpress and you can also view the manual there. Pretty damn cool. If I had a super nice mic and a super nice soundcard I would do REW, but I dont. Omnimic is one package, easy to use, and very robust software suite.

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #49 on: 3 Feb 2012, 02:36 pm »
I'll snipe this question in there since the right people are looking, do planars require a different measuring technique than box speakers?

To the OP look at the omnimic. Everything you need in one box. Better quality than a rat shack meter and no need of a fancy soundcard. That's what I'm doing. Its at partsexpress and you can also view the manual there. Pretty damn cool. If I had a super nice mic and a super nice soundcard I would do REW, but I dont. Omnimic is one package, easy to use, and very robust software suite.
Hadn't run into Omnimic. Interesting. That's a fair chunk of change. Might be worth it after reading all the problems people have had trying to get REW to work with brand/model x soundcard and OS whatever. Have to think about this one.
Thanks for the info.

Rclark

Re: OK Guru's - I'm lost
« Reply #50 on: 3 Feb 2012, 07:19 pm »
Doesn't appear to be much more expensive than. A nice soundcard and mic, (they were just on sale for 249), and besides that, for guys like you and me, it's apparently both easier to learn than REW and with the latest updates, pretty much on par.


 go download the manual and check it out, you'll be pumped.

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #51 on: 10 Feb 2012, 04:46 pm »
Doesn't appear to be much more expensive than. A nice soundcard and mic, (they were just on sale for 249), and besides that, for guys like you and me, it's apparently both easier to learn than REW and with the latest updates, pretty much on par.


 go download the manual and check it out, you'll be pumped.
Well, the Omnimic showed back up as in stock at Parts Express, so I pulled the trigger - should be here Tuesday.
I did my first round of OC703. It definitely sounds different, with a bit better separation of instruments and individual voices. Seem to have picked up a bit of glare somewhere around 3-5k (guessing) - no clue as to why. Didn't really change anything else.
Think I'll keep everything as is for now, wait for the Omnimic. I'll take out all the treatments, measure and get a baseline, then start adding/moving -measure each time and see what's going on.
Fun times ahead.

tasar

Re: OK Guru's - I'm lost
« Reply #52 on: 10 Feb 2012, 07:22 pm »
Great......any Omnimic-like solutions for MAC users ? Is the Rat shack SPL meter w. onboard "mic" unreliable without certain external cards ? Seems Apple's internal cards would be quite good.

Cheeseboy

Re: OK Guru's - I'm lost
« Reply #53 on: 10 Feb 2012, 10:36 pm »
 Where did you place the OC 703?  Are there any other treatments in the room.  Good news Mrs Cheese approved the Art Panels for the left and right first reflection points!  And We're Off to the Races.  She wants a new couch I want Art Panels from GIK.  I have to beat her to the punch.

Do you have any AC filtering in the system?  I have the same glare point.  I'm pretty sure it's the AC line.  The battery pre helped but it is affecting everything.  I think I'm gonna havta to buy a PI BUSS from Dave.   

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #54 on: 11 Feb 2012, 02:12 am »
Where did you place the OC 703?  Are there any other treatments in the room.  Good news Mrs Cheese approved the Art Panels for the left and right first reflection points!  And We're Off to the Races.  She wants a new couch I want Art Panels from GIK.  I have to beat her to the punch.

Do you have any AC filtering in the system?  I have the same glare point.  I'm pretty sure it's the AC line.  The battery pre helped but it is affecting everything.  I think I'm gonna havta to buy a PI BUSS from Dave.   
3 OC703 panels vertically behind each bookcase (2 on bottom 1 on top so it runs clear to ceiling) and pillows stuffed behind them. GIK 242's at first reflection point. Temporary wedges holding polyfil on front ceiling corners. I don't want to wrap anything in cloth until I'm pretty close to final on where what goes. Figure I'll hold off til I get the Omnimic.
No power treatment yet - that's going to have to wait at least until next months budget ( I don't count the Monster power strip - nothing fancy)
Glad you get to use some GIK stuff. Still wiaiting to hear on shipment of the PI Audio AQD-1's.

Cheeseboy

Re: OK Guru's - I'm lost
« Reply #55 on: 14 Feb 2012, 03:56 pm »
How are things going?  Good sound yet?

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #56 on: 15 Feb 2012, 12:26 am »
How are things going?  Good sound yet?
Guess I'll answer the second question first: Good sound? Yes. Great sound no.
How are things going? Frustrated again.
The Omnimic showed up this afternoon right on schedule. First step after getting the software installed is to get a calibration file for the mic. Their website says that they have the file - just "right-click" on the link and "save" or "save-as" to a file in the software. When I right-click, my only option is "properties". I can't save or save-as.
Sent an email to Dayton (manufacturer - in Dayton Ohio) support. Hopefully they can just send the file back via attachment and I can get it that way. Means another day of delays though. :thumbdown:
Ah well. Anne's out of town, bought a few more Blurays, and I'll crank some action flicks this evening. :icon_twisted:

Cheeseboy

Re: OK Guru's - I'm lost
« Reply #57 on: 15 Feb 2012, 02:13 am »
Get loud brother!

Rclark

Re: OK Guru's - I'm lost
« Reply #58 on: 15 Feb 2012, 03:43 am »
yeah still haven't bought mine yet, post pics of your first graphs and all that  :green:

SoCalWJS

Re: OK Guru's - I'm lost
« Reply #59 on: 15 Feb 2012, 04:57 am »
Get loud brother!
U-571. Haven't seen it since it first came out on DVD. Popcorn flick, but.........

What a sonic tour de force on Blu!!!

wow....................