glennconti

Reviews the absolute sound February 2003 If you have a subwoofer--and nowadays who doesn't--this BEHRINGER digital EQ device is an opportunity to make a remarkable and remarkably cheap sonic improvement in your system, be it in home theater or two-channel music. Think of it this way: The world is full of subwoofers that will produce deep, low-distortion bass. Thunder is no problem. What is a problem is low bass with smooth frequency response. Few subwoofer/room combinations are free of annoying peaks and dips--especially peaks, those infuriating one-note booms. [...] But with BEHRINGER, you can always make it work out, and most systems need help in this area. [...] I believe that every audiophile who does not own a digital EQ device ought to think seriously about buying the BEHRINGER just as an experiment. [...] Looks like it's time to test my room frequency response in the lower frequencies and, if needed, save my money for a Behringer experiment.

After I get the Samsom E62 setup and a flat frequenct response for the 1/3 octaves, I am going to retest the frequency response with new higher resolution low frequency test tones. This is a quote from Real Traps website which offers a free low frequency test tone cd: "There are a lot of commercial test tone CDs available, but all of the CDs we've seen suffer from the same fatal problem: The tones are spaced at either 1/3 or 1/6 octave intervals, which is far too coarse to assess the low frequency response in rooms the size you'll find in most homes." This agrees with what Artto says. "Therefore, we supply only low frequency sine waves, in 1 Hz increments" This will be interesting. However, they also don't recommend using correction factors for Radio Shack SPL Meters [*-)] So I am a little confused. "Some test CDs "calibrate" the level of each tone to match the known inaccuracies of the Radio Shack SPL meter, but we didn't do that for two reasons. First, meter calibration offsets are not that useful because all Radio Shack meters are not the same. More to the point, low frequencies are usually accurate enough even with inexpensive microphones. We compared our Radio Shack SPL meter to our own expensive AKG calibrated microphone, and they were within 1 dB of each other below 600 Hz. The main point of these tones is to find the major peaks and nulls at low frequencies, and any inexpensive meter is fine for that, calibrated or not." Should I correct for the C-weighted drop off or not? Any comments would be appreciated. Thanks.

Artto, Thanks for the advice. I dont want to spend much for the experiment. So I got a used 62 band (31 left and 31 right) equalizer on ebay. A Samson E62 for $56 plus freight. This 1/3 octive setup corresponds to my Rives Audio test tone cd. The Sampson E62 also has 1/4" inputs and outputs so I got a bag of 10 1/4" male to RCA female adapters for another $8 on Amazon. This setup is nowhere near what you have but, as per your suggestion, it will be much better than the 10 band EQ I was originally considering. If the experiment goes well I may get a DEQ2496 and sell the Samson E62 for what I paid for it. Thanks again for your input. With this forum's help I don't feel like I'm gropping around in the dark as much.

After seeing Artto's post: http://community.klipsch.com/forums/t/162245.aspx I am wondering if I am missing something? I don't want to pop the bucks ($330) for a Behringer DEQ2496 (plus it looks like it uses only balanced inputs and outputs - which I don't have) but I am wondering if I would hear any difference by using a 20 band (10 Left and 10 Right) equalizer? I can pick one up cheap on craigslist. I can get one for less than $50.00. I may just get it and experiment around with it today.

Thanks for the input. I love the way my stereo sounds and it looks like the frequency response graph is not showing much of a problem with room acoustics. I did another frequency chart. This time I normalized the settings so the bass response was not getting clipped. Basically it showed, if you average out the peaks and valleys, that my subwoofer is set about 6 db "hotter" than the H3's. This gives me just about the right amount of bass to my taste. My bass tone control is set at 12:00 (as are my other tone controls) at the receiver and it's all good. Thanks again for looking at my chart and room layout. If anybody else wants to chime in feel free.

This is the recomended sub location in the owner's manual. My top wall (horizontal) is an outside wall and the verticle wall in my house is a load bearing wall. The driver on the left as you face the sub is the active driver and the driver on the right is the passive driver.

Hi QH, Yes, the blue dimension is 3 feet. The mic was four feet from the wall and the ceiling is 9 feet tall. --Glenn

There is a sofa drawn to the left; the microphone "M" on tripod is located near it. The speakers are located on the right wall labeled "H3" on either side of the entertainment unit. The sub is in the top right corner with a diagonal orientation (labeled "S"). The room is 15 x 15'. Each grid is one foot. Let me know if you need anything else, thanks.

This was measured with a RS analog meter with corrections applied (80 db scale C-weighted Slow). Anything greater than +/- 10 db I didnt change the scale. This occurs at 10KHz and above and down in the 25 - 40 Hz range. The speakers are two H3's and a Sunfire True Sub. Any comments would be sincerely appreciated.

I always wanted horn based Klipsch speakers after hearing them. I researched on the net a good pairing and was happily surprised to see the Marantz 22xx being recommended. I think that series of receiver is very attractive looking too. I picked the 2245 because I wanted to have power in reserve incase I changed speakers. The H3 sounded great for mid and high but I found myself wanting more bass. So, I went out and got the Sunfire subwoofer. I haven't tried the H3's with any other receiver. But I hear tell from other forum members that vintage Denon is also a good match with them if you use CD's (look for a DAD -digital audio disk input). I dont use a turntable but that is a special consideration too (good phono preamp section).

I would see if you can demo a 22xx to see if you can experience a difference from what you have now. The 22xx series are very beautiful peices of equipment. But if you can't tell, why spend the money?

Here is an interesting link I found. http://www.hometheaterfocus.com/receivers/amplifier-sound-quality.aspx

Based on the above I wouldn't listen to the stereo above like 90 db. (my other post got cut off)

TABLE G-16 - PERMISSIBLE NOISE EXPOSURES (1) ______________________________________________________________ | Duration per day, hours | Sound level dBA slow response ____________________________|_________________________________ | 8...........................| 90 6...........................| 92 4...........................| 95 3...........................| 97 2...........................| 100 1 1/2 ......................| 102 1...........................| 105 1/2 ........................| 110 1/4 or less................| 115 ____________________________|________________________________ This is from OSHA website. I googled "government noise thresholds". In case anyone is interested. Based on this I wouldnt listen to music over 90db for any extended period of time.

Did you mean Threshold of Hearing (bottom red line)? The Threshold of Pain (top red line) at 40Hz on the graph is like 125 db. That would seem to be pretty loud and painful.

IMHO the reason level bass would sound flat is we don't hear bass tones as well. So they need to be tweaked up.

I just found this thing. http://www.auralex.com/sound_isolation_subdude/subdude.asp It costs about $50.

If you are on a budget, you can pick up some Heresy I's or II's for $250 to $350 and than update the crossovers from Bob Crites for another $175. The Heresy III's cost bout $800 used if you can find them. New H3's are about $1300 on ebay.

Non-skid carpet stuff worked great for mine. I cut a 12 x 24" peice and folded it in two and laid it under my sub (I have no feet on my sub - they had walked off of the previous owner). I heard of a guy that used four hockey pucks on a larger sub but I think that would be overkill for a Sunfire.

Well at least you can see I am not the only one who thought the correction factors were due to inaccuracies in the meter. Thank you for your prosoundweb.com article. I am shortly going to have a Radio Shack Analog SPL meter and I have also ordered a Rives Test CD 2 (Radio Shack Corrections built into the test tones) and I already have a tripod. This should make my experiment as easy as possible. Especially since I only have a 2.1 setup. I am expecting everything to be flat except around the crossover points 5KHz, 850Hz and 80Hz. Has anyone else used the Rives Test CD and procedure? It seems pretty straight forward: http://www.rivesaudio.com/files/TestCDinst.pdf

Quote from http://forum.blu-ray.com/showthread.php?t=38765 Corrections to Radio Shack SPL Meter When using a Radio Shack SPL meter, you need to adjust for the fact that it's not accurate at all frequencies. Add according to the numbers listed below. These frequencies are 1/6th octave apart. 10.0 hz: +20.0 db 12.5 hz: +16.5 db 16.0 hz: +11.5 db 20.0 hz: + 7.5 db 25.0 hz: + 5.0 db 31.5 hz: + 3.0 db 40.0 hz: + 2.5 db 50.0 hz: + 1.5 db 63.0 hz: + 1.5 db 80.0 hz: + 1.5 db Etc Etc So do we have a discrepency here?

PM Sent

I like that "fallen on deaf ears". But I can't obtain an analog RS meter. Thay are apparently discontinued. But I'll call the local RS to make sure before I drop any coin.

My local music store has one for 39.95. I'm going to pick it up after work. If it turns out to be a piece of junk it wont be a tragic loss. Should be a fun little experiment.

Maybe I can get one locally but keep the receipt if you know what I mean []