Then i read elsewhere that all of that is nonsense, and the gain IS just like a volume meter.. Dont know what to believe i guess. I do know that turning that gain knob definitly plays a factor in whether or not the amp is clipping. and the sub definitely does work harder when the gain is up, and not as much when the gain is down. Damn, wish one of you audiophile pros lived in central florida, to get me sorted out.
It all depends.
It all depends on:
(1) Input signal
(2) Level controls settings for individual speakers
(3) Volume control setting
(4) Gain structure of the AVR.
From the User guide:
Input Sensitivity and Impedance (Unbalance)
200 mV/47 kΩ (LINE)
Rated RCA Output Level and Impedance
200 mV/470 Ω (PRE OUT)
Maximum RCA Output Level and Impedance
4.6 V/470 Ω (PRE OUT)
The gain structure of the AVR appears to be unity gain from line inputs to preamp outputs. This would presumably be obtained with all speaker and main level control set to maximum or zero dB if that is different from maximum.
The gain structure from digital inputs appears to be undisclosed, but one might presume that digital FS creates the same output as 200 mV RMS applied to any of the analog line inputs.
Bottom line is that the preamp outputs of this AVR may not be a good match for use with many power amplifiers. Not enough voltage.
Ive got to say, im on the verge of being a little bit pissed. I let people talk me into DIY over internet direct, thinking "bang for the buck", but im starting to wonder..
To be honest, most of what you wrote, i dont totally understand. But from what im reading elsewhere (so much conflicting information), the receiver sending a voltage that low, would mean i would need the gain way up on the amp.. I have it less than noon right now.. any higher with music, and it clips at volumes that i listened to before installing this sub/amp.
I dont know man.. Im a bit aggrivated. I dont plan on switching receivers. and to be honest im about tapped out on $$$. ill be getting the second sub, as it was in my original budget, but this is starting to get more and more pricey to acheive questionable results.
Thanks for your input. Again, it would be nice to have someone thats into this stuff close by, with meters, and more (and consistant) knowledge then me, to get me along the right track. Unfortunately, its not really something any of my close friends are into. Half of them think im crazy for how much i am into my audio.
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That's a good test. Set the gain to max on the amp, and see what Audyssey puts the sub level at. See how it sounds that way. I don't think your amp is faulty, just gotta figure out where in the chain the problem lies.
If it is the preout voltage being the issue, a minidsp can fix it.
Bedroom: Definitive BP30, CLR2000 Also have had: BP7000SC, BP8B, BP10B, BPX, Dayton 15" HF subs, Rythmik F15
First, you need to clarify clipping the input voltage to the amp versus amp output clipping. In the good news dept., the Onkyo 809 has plenty of pre-out voltage. I have that setup (809 + ep4000, but different subs), and the two match up just fine (rca out from avr into 1/4 inch amp left input works fine as well). I think Josh Ricci has tested the 809 in a thread here, and the output voltage can actually go alarmingly high. (search for that thread). When running my 809 into a dsp1124p, I can made the input signal meter clip (or at least hit the red light, did not actually measure with a voltmeter) with subwoofer output at -10 on the right material. (Skyfall train crash scene at about 0 master volume will do it).
Second, if you're running the ep4000 into a 4-ohm bridged load, I think you should have no problem hitting/exceeding xmax on that woofer. That is a lot of peak watts, assuming your amp is working correctly. Can you watch the sub and see how much excursion you're getting? It's easier if you put a dot of tape or something on the cone (I have a dot of white-out on mine). You need some material with real <20 hz content. I was surprised when setting up my system how hard that can be to find. Some dubstep/etc that I thought would rock had very little content below 40 hz. It gets loud of course, but you don't see the subs move much with that.
Third, "reference" is probably not what you think it is. If you calibrate to reference with audyssey, that means reference when at 0 master volume (pretty darn loud). The first thing people usually say is wow the bass is incredibly quiet under normal circumstances. If you're listening to music at -20 (I think that would be 64 on your onkyo), you're going to basically hear no bass. Most folks calibrate but then run the subs hot, either by turning up gains or upping the pre-outs. (see "house curve")
Re: the ep4000, the setup diagram produces no end of confusion. Is your right gain knob turned all the way down? (should be). Are your speaker wires on the center two poles on the back? (should be). Is your sub in/out of phase with your mains?
A SPL meter would really help in this situation to see what kind of SPL you are getting before the clip light turns on.
This is not perfect but will give you an idea... Disconnect ALL speakers.
Set sub trim to 0db and Audyssey disabled.
Play a sine wave at 60hz through the receiver and set the master volume at 0. MAKE SURE ALL SPEAKERS ARE DISCONNECTED!
Use a multimeter set at ac voltage and measure the sub output.
With DIY you have to rely on yourself to do the troubleshooting if something is not working right. For some people that can be a challenge because they don't understand all the little details about the project or have the correct tools.
DIY Sound Group: Information and Tips
Display - Panasonic TC-P55VT50
Receiver - Onkyo TX-NR809
Blu-Ray Player - Pioneer BDP-320
Front - Pioneer SP-FS51LR (with modified pedestal bases)
Center - Pioneer SP-C21
Surround & Surround Back - Pioneer SP-SS41LR (the 'SS' is for custom boxes)
Subwoofer - Eclipse 88100DVC (x2),...
|Behringer Europower Ep4000 Professional Amplifier|