Problems with Behringer amp and Denon AVR - Page 2

Yeah. I get a super hot LFE signal from my Onkyo TX-NR3007.

Agree'd. I wonder where all this hearsay is coming from. My 3009 has no issue with LFE signal either.

My 807 was way up over 6 volts with less than 1% thd. 886 is somewhere north of 12 volts.

My Denon clips my crown pro amp. clearly enough signal.

And where is master volume knob on reference scale and the sub trim level (AVR) when denon manages to clip the signal???
Edited by braveheart123 - 12/13/12 at 7:35pm

Already did only a year ago. That article, though written very comprehensively, mainly deals with full-range signal. We are discussing max 100Hz and below bass frequencies where wavelenghts are long enough to exhibit any inherent and, most importantly, significant noise properties in the input/output signal.
Edited by braveheart123 - 12/14/12 at 12:49am

May be u just rushed through my post. I never said I used internal test tones of avr to set the gain level of pro amp. I used internal test tone only AFTER setting the correct gain on pro amp with a wide-band 60-90Hz pink noise. And by the way, this pink noise was recorded at 0dBFS and while playing it, I put AVR in 2-channel stereo and disabled Audyssey and DynamicEQ along with BFD in bypass mode.

Re-read....

The gain on AVR not dropped.
Sensitivity level knob on ART CleanBox Pro at max position.
And guess what....the level attenuator on Crown went further north east. It was on 12 o clock position before and now at 3. I tested it at my reference volume on avr (75dB spl on rat shack)......no clipping. Alpine is taking more beating than ever for a very clean hit. The output is a tad crude but that's coz it is a test box and I built it from chipboard. I will do the final build with MDF.
Edited by braveheart123 - 12/13/12 at 9:33pm

In Direct Mode, your sub will not ouput any signal if subwoofer mode setting in avr is set to "LFE". It must be "LFE+Main".


Also, do not use internal test tone of the AVR. It is recorded at -30dBFS. Download a 60Hz sine wave recorded at 0dBFS or alternatively you can create your own with NCH tone generator. It is free. I use a 0dBFS 60-90hz pink noise for this coz it gives me an average of the spectrum.

Once you have a 0dBFS 60Hz test tone, use that keeping the sub trim level at 00 on avr and master volume at your max reference. For gain matching, I use 2-channel stereo mode disabling Audyssey, Dynamic EQ, and BFD in bypass mode. Then raise the output knob on ep4000 from its lowest position tick by tick till the clipping lights show constantly lit or start blinking (to be safe). Make sure all speakers including sub are disconnected. If using Direct Mode or 2-Channel Stereo mode, disconnecting front left/right and sub is enough.

Hope that helps.
Edited by braveheart123 - 12/13/12 at 10:03pm

Re-read Post #7

Reference is when your system's speakers are all calibrated to 75dB's and the volume of the AVR is at -0. There is NO other reference. If you listen that loud, then that is where you want to start your AVR off with the sub trim level at 0. If you only listen at -15 or even higher, start there. after you get to solid clip lights, you will want to back the amp down until they aren;t fully lit anymore.


At a 75dB, no one should clip, that is just plain silly.

At home reference volume, the speakers are playing at 75dB, and sub 10dB hotter at 85dB coz of 10dB hotter LFE recorded in the mix. During 20dB transient bursts (action scenes), speakers play at 95dB and sub at 105dB. That is astronomically loud in home environment. So, 105dB sub output with NO CLIPPING is the target I shoot for. And I successfully achieve that and like me many many more HT enthusiasts also do, um sure.

No pun intended, but you are way off on reference volume stuff. Read more

I thought reference was 105 db speakers and 115 db subs?

You did good for the bold part at least! I guess we can say you are making progress. After that you fall apart with misinformation, once again. Reference is actually 85dB with 20dB headroom for peaks. Systems need to be capable of 105dB peaks for the speakers and 115dB for the subs. Considering you are not using full range speakers for each channel of your system and then you will also have channel summing for the LFE when you redirect bass to it, so a sub system capable of 120dB peaks is not a bad suggestion.

Please read this: http://www.thx.com/consumer/thx-technology/thx-reference-level/

You are correct that you run your noise and calibrate to 75dB, but this is -30Dbfs signal! PLEASE PLEASE PLEASE stop posting misinformation. Get your facts straight before you confuse some poor chap that is trying to set his system by the actual proper guidelines.

FWIW, most bump boxes should be set at half if they have a gain knob. This is called the "detent" position and keeps the converter to changing the signal exactly to spec.

It is for the peaks, 85dB for dialogue, I just posted a good link to explain.

Haha I guess THX spec website is off then? Now you are really diggin deep pal.

This is what you said. I am very proud of you that your sub is not clipping at 75dB. If it did, then perhaps you should run down to Best Buy and scoop the cheapest one they have there as it will outperform whatever you have tossed in your chipwood "testbox"

That's not entirely true. Technically I could set reference up any given volume level I choose. Not all receivers are setup for reference at 0db because not all use the same display function. A friend of mines starts at zero and goes up from there.

THX badge is nothing more than a marketing gizmo to charge extra money and snag naive end users into buying mediocore products. Not necessarily though. You seriously require some reading regarding levels and your so-called REFERENCE level.

+1

You are right, and some AVR's reference -0 is different than others as well. Some movies are also not mixed to exact THX standards. Some are hot, some are less than ref. but generally speaker, reference is with your AVR at -0 and your speakers calibrated to 75dB with the internal -30dB noise.

I said ..... HOME.......open your eyes buds.

Which is exactly what that article refers to. I am not going to sit here and argue with you over what 90% of this forum and HT enthusiasts in general refer to as "reference level." You can create your own reference level all you want, but when I am talking about it, I am talking about 85dB with 105 dB peaks on the mains, and 115dB peaks on the sub channel. My system can do this with ease.

The difference is "relative vs absolute" volume reading. Most modern AVRs with automated correction that I have setup have the Relative volume display which is relative to reference, with "expected" reference to occur at the "0" reading. However most home setups run out of gas waaay before reference in one way or another. I haven't seen an AVR without at least the option for relative volume display in yeaaaars.


Marty,

another thing to strongly consider is your high pass. Without the highpass filter you will likely damage the driver and it won't sound good either with the woofer flopping around under tuning. The EP4000 is flat to 5hz minus a db or two. It doesn't roll off @20Hz like your stock plate amp. This was on purpose to protect the driver.

Another thing to consider is you have no way to control the power to the driver. That amp puts ~650W into 4ohms which is nearly twice the power the original amp was capable of. This might sound good MOAR POWER!!!!!, but in reality without a high pass and too much power you will likely kill that driver.


OPTION: You could always seal the box and not worry about the high pass. This will however decrease the output capability of the sub but should help keep the driver out of trouble. Notice I said help, b/c in ~3.0ft^3 sealed that woofer still cant take 650W and stay under x-max. I sealed a couple of mine this way and am currenlty using them sealed but with only 250W each.

Not trying to discourage you, but if you do this like your saying you better have better disipline with the volume control than I do!!!!!

75dB spl is for home use man, come on and stop debating over something which I think is flying over your head. That's why i say READ MORE

Oh? So the THX standard that I keep referring to, and that many of the high in sound engineer mix their movie soundtracks to, is just a marketing scam? Perhaps badging equipment is, but not the standard that has been set forth that many of your Blu-Rays are mixed to.