No matter how great the speaker and electronics, the speaker must be properly placed in the room. Given the weight and size, these babies are often just "plopped" into an approximately good position and left to disappoint the owner forever.
IMHO, you should beg and pay a Sumiko dealer to come out and do a Sumiko Master Set for you. Don't change any equipment until you do this. You can't judge a system until the speakers are properly set. In the few Wilson systems that I've heard, this is a chronic problem, with great speakers not reaching near their potential due to lackluster placement.
See my review of the Sumiko Master Set and Guidocorona's comments regarding the Master Set of his system for more in-depth discussion.
Dave |
05-15-08: Flkin said:
"In addition to speaker placement (so critical for Wilson speakers, need to get them right down to the last 1/2 inch), ..."
Some of us believe that you need to get it down to 1/16", really, it's that critical. However, the reward is well worth the trouble.
Dave |
05-15-08: Rgs92 said:
"Reading this could scare anyone away from high end audio..."
Yes indeed, as would the prospect of spending tens of thousands on speakers and having them perform marginally.
You can spend all the money you want on equipment, but if it's not set up correctly it'll likely disappoint.
Dave |
Kana813, it's about the balancing the sonic energy. Notice that there are big openings on each side and they're pretty close to the wall behind them and one wall is straight and the other juts out right behind the right speaker. All of those would be avoid be avoided in more "traditional" placement methods.
Did you read Guidocorona's more limited discussion of the Master Set in his space?
Dave |
I wonder how we'd measure the intermodulation distortion at the listening position, do you have any ideas? This is about way more than frequency response.
Dave |
How and why would I forget IM Distortion???? It's way more important than EQ in making the system "listenable". You're shooting at the wrong target when you put all your focus on EQ.
Dave |
"IMD is is the result of two or more signals of different frequencies being mixed together (as in a stereo speaker set up where the signals are not always equal in frequency), forming additional signals at frequencies that are not, in general, at harmonic frequencies (integer multiples) of either." (Wikipedia)
"A comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. The frequency response of a comb filter consists of a series of regularly-spaced spikes, giving the appearance of a comb." (Wikipedia)
I think that both exist in our speaker systems. Prior to experiencing the Sumiko Master Set I dealt with these issues by moving my speakers six-plus feet out into my room. This sacrificed bass performance and still could leave female voices "shouty" or "hooty" and trumpets hardedged and harsh, rather than brilliant.
The Master Set minimizes these negative effects, rendering the system much more transparent and detailed, while removing stress and harshness. It's like a major upgrade in equipment when you experience it.
Dave |
Kana813 said:
"I doubt you're getting flat bass response."
Duh, who is?? However, very precise placement has mitigated the most obtrusive nodes and balanced the bass vs. the midrange. Moving the speakers fractions of inches can excite nodes
That's way less important than the phase/comb/IMD effects that so gravely impact our musical enjoyment. When you take care of these issues, gone is the harshness, fog and veiling caused by these distortion components.
Dave |
Shadorne, I don't know how to measure it or demonstrate it, but I believe there is IMD caused by the interaction of the two speakers with each other, not the room.
As a musician I often hear beat tones and difference tones when playing with others. These same kinds of things are going on between the two speakers. I've also experience the power multiplication when a group (say five trumpeters) gets totally in sync, totally in tune and playing with equal resonance. It's hard to explain, but when you experience it it's unforgettable. Anyway, getting the speakers ideally placed within their acoustic space and relative to each other is very important, no matter what we call it.
Dave |
Yeah, but you suffer with IMD, comb filtering and other artifacts that are much worse than any EQ issues.
You seem to have no idea what I'm talking about. To that it avoids exciting bass nodes it has a little to do with EQ, but it's mostly about removing distortion.
Dave |
You haven't proposed a measurement that would verify improvements in IMD or comb effect. I'd love to measure it, but I've never read of anyone doing it. If there's a way and some resources that you could point me to, then maybe I could measure it with the help of the Colorado Audio Society.
I've read much about TacT and I'll leave it at that, given the issues being aired over at the Asylum.
Unless you've addressed IMD or comb filtering in your set up, then you almost certainly have it.
How does bi-amping impact IMD and/or comb filtering. Seems like adding devices to the signal path would increase the chance of IMD, in particular, rather than decrease it.
Dave |
BTW Kana813 I looked at your system and see that you did, either on purpose or intuitively, address comb filtering and to some degree IMD by moving your main speakers way out into the room. Then you offset the bass loss with subwoofers. I assume that you attenuated the bass nodes electronically.
I agree that your method can work reasonably; however, I suspect that further refinement of the main speaker placement using Master Set would further improve your setup. Integrating the subs is often problematic, but something that can be addressed with some work.
Dave |
Thanks for the link Bob, but that link is to an "In Room EQ Analyser". I couldn't find anything about measuring IMD, comb effect or anything similar. Where is that part?
Dave |
