AVS Forum Special Member
Join Date: Dec 2005
Location: South Florida
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
20hz HP dial setting
12hz HP dial setting
We were listening to War of the Worlds at -5 on the receiver, with the subs cranked several dB hot over matched and audyssey eq and audyssey equalizer in use (so an additional couple + dBs hot from that since I was still below reference on the main volume knob), and the EP4000 amplifier was occasionally lighting up the clipping light (not solid).
|Bear in mind the Mic2200 was not in place and thus there was no LPF of any sort engaged.|
|Which unit are you using now for that purpose counsil?|
|I know you've been through several lately, but can't remember what models you've tried?|
Archea, some thoughts -
I don't see the need to run a HPF on these Caps, though I suppose it does save the amp from having to dig deep for those sub 20hz passages in movies/music, and I guess it does keep the Caps from unloading below tuning during those selections. With all the different attenuators in the mix, from the receiver to the different Audyssey features to the Mic2200 to the EP4000, you have a lot of variance in the signal chain, and that's problematic. I feel like disabling Audyssey for the subs completely, getting a 2x4 Balanced MiniDSP for HPF (even if it's not functioning perfectly) and EQ, and turning the knobs all the way to the right on the EP4000 would simplify things considerably.
As for the port noise, are you certain that's what it is? Could you describe it a bit more for me? I can hear an audible difference between port noise and the driver making noise. I can get the driver to make noise if I run sine waves significantly below tuning, but I'm hard pressed to get the port to make noise during program material. I'm not doubting your diligence in attribution, per se, but find it unusual that there is so much variance in our subs. Perhaps try to revisit this situation and attempt to localize the sound you're attributing to port noise just to make sure? For me, it sounds like the driver is flapping like a sail in the breeze, or slapping very lightly against something, and it's most definitely the driver, not the port(s), making the offending sounds, as verified by wearing pro earplugs and going right up to the cabinet and listening for where the sound is emanating from.
I have, however, heard port chuffing in excessively high output situations during sine wave testing above tuning, but it's very rare. But this is different from the noise I can reproduce from the sub's driver during certain high output situations below tuning. Also, stuffing towels in a port isn't the same as having a port plug. Do you have the port plugs? I know that with improper seating of the port plug, I can get the port to make noise on lots of material at moderately high output levels, and this is definitely caused by the port plug not making a proper seal. It's alternately a whistling or a wheezing noise.
Though I doubt it's contributing to your issue with the EP4000, in the future take Ricci's advice and don't run pro amps off the power conditioner or UPS. They're ok to run straight from the wall, even in areas with crap power delivery. And I understand what situation you're in - I lived in KCK off of N. 81st Terrace and in Lenexa off 91st St. for quite awhile. KCK had terrible, terrible power by comparison, with exactly the same problems you mentioned.
Good luck on the issues you're experiencing! I hope they're resolved quickly and fruitfully. I'm still moving in and unpacking all my stuff down here in the desert, and have not as such had time to dial everything in yet. Hell, I don't even have my center channel implemented due to having nowhere to place it. I'm gonna build a wall shelf and hang it below that to create the proper imaging location above the TV. Grad school started on Monday and has me insanely busy. I've been getting to bed by 9 or 10pm every night!
Actual phone call (see pic to left):
Tech (responding to laughter): "I'm sorry sir, did I miss something?"
Me: "Yeah, a case of Diet Mountain Dew walking across my living room."