The importance and in fact the audibility of Doppler distortions in loudspeakers is a hotly debated topic, not a certain problem. And definitely no big deal unless the music contains low bass notes mixed w treble and nothing in between. Moreover it’s the same issue or nonissue with electromagnetic speakers as with ESLs.
A Discussion About What Level Of Analog To Stop At
So this is a bit of a friendly discussion, a sharing of information, and perhaps a bit of a what if thread.
As we acknowledge, the rooms our stereo’s reside in are a significant factor in how our audio systems sound. Now this discussion takes place mostly in the arena of speakers, and perhaps amplification for those speakers. I don’t believe I have read threads where it comes up in context to our source components. But I am wondering if it should?
In terms of myself, I only run one system unless you count my headphone rig. Truth is I rarely listen to that and I wonder if it is worth the money I spent there. But I am a consolidator and climber when it comes to audio gear. I also have an understanding with my patient spouse that I keep the audio gear in one room. I suspect if I tried taking over another room with audio gear, she would bury me in a shallow grave in the back yard.
So I have run of the living room within reason. Now this is the best room for audio in the house, but it is by no means perfect. it is 16’W by 20’ L with 8’ ceilings that are textured with acoustic popcorn. The flooring is short pile carpet with heavy pad. There is a dining room off the left wall, so only a half wall on that side. The right wall has a picture window in it. 6’L and 5’T. The back wall has french doors with glass panes. There is a little notch in the back left corner about 3’L by 1.5’D, its where they put a small bathroom on the other side of the wall. Equipment rack is on the side wall under the window. The speakers on the short wall on each side of a fireplace. Listen chair is 4 feet off the french doors.
Stereo consists of:
Martin Logan CLX ART speakers w dual Velodyne HGS12 subwoofers
Classe Omega monoblock amplifiers
Trinov Amethyst pre-amp (the DSP functions are a prime consideration in buying)
Cen Grand DSDac 1.0 Deluxe DAC
BPT 2.5 Signature power conditioner
Now all the analog gear is where it gets messy, and my consolidation thoughts are kicking in
Turntable #1 SOTA Cosmos Eclipse/SME V/Transfiguration Audio Porteus
Turntable #2 Scheu Analog Das Laufwerk No2 with Schroder CB-1L and Ortofon Verismo. Second arm Dynavector DV505 that gets used with an Ortofon MC2000/Ortofon MC3000 II/Kiseki Blackheart
Phono stages are a BMC MCCI Signature ULN, a standard BMC MCI Signature, and Esoteric E-03. Have an Ortofon T2000 SUT to use with the MC2000.
As a consolidator I sometimes wonder if all of this is necessary. The money is spent and this is kind of my audio kitty funds. I tend to keep those monies separate and often save and then sell pieces being upgraded to afford that next step. The reality is that often I cannot have to expensive pieces side by side and decide which I like the best. Since I also shop Audiogon and USAM for used gear it’s not possible to listen to candidates. As a consolidation I look at what is out there. For instance, when I tally things up I could possibly afford a Walker Proscenium that happens to be on Ebay at the moment. I would be down to one table, one phono stage, and two cartridges. One thing that stops me is that gold on the Walker is damned ugly, secondly, I am not sure I got room for the pump assembly. My system is a bit large for this room as it sits.
As I am writing I wonder if this room can really support a higher tier of analog gear than I got. I think some would argue that this room is limited in ways to compromise even what I have. The sound is very nice, better than I hear at many shows, and in other audiophiles’ homes I have gone to. We have a local audio group, and I haven’t heard anything I like better. In the past I have used the MC3000 II cartridge as a casual listening tool, but with the CEN GRAND DAC the sound is so nice I really don’t need to do that anymore. Still need the Dynavector arm though if I want to play the MC2000. Now all of these cartridges sound very very nice, and I could live with any of them. Truth is I like the Transfiguration the least. Or I think so till I spend about a weekend listening to it.
One thought is to choose one table and sell it all off and maximize that one. The other is to keep the Verismo and probably the Kiseki. Buy the very best table and arm I can with all the funds gathered once I sell all that stuff. The question I cannot answer for myself is ...is this worth it given what my room allows this system to do? I have a small amount of room treatment with wood diffusers, ART series acoustic panels, and the DSP function of the preamp. But I cannot turn this into a full-on treated room because of the basic limitations of it.
I have probably made posts in the past in other threads putting ideas like this forward. But I don’t know if I ever made a comprehensive post with all these thoughts. laid out. If you feel its repetitive, I do understand. However, if you have thoughts or ideas, I would surely be interested in reading them. Take the conversation wherever makes sense, as this is meant to be a wide-ranging discussion. Thanks for any of your contributions!
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- 65 posts total
Dear @lewm : Always will be an issue if the main speakers crossover 250-300hz or even a little lower and the speakers goes as the neonnigth around 30-35hz. It's a certain problem depending on that crossover frequency and yes depending of the quality of the drivers will be more lower/higher audibility, but the problem is there. Like it or not.
" low bass notes mixed w treble and nothing in between " this makes no sense to me: do you? because harmonics are there.
R.
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@lewm , It is not a theory and there is nothing to debate. It is much less of a problem for two and three way speaker systems because the bass driver's range is limited. It is a huge problem for our ESLs because they are full range. It is extremely noticeable with bass below 40 hz which few recordings have, but it still modulates the sound up to about 80 Hz. You hear it as a warble almost as if the speaker is shaking at high volumes. I think some do not notice it until it is gone. It bothered me right away as I tend to listen to bass heavy material at higher volumes. This resulted in my getting RH Labs subwoofers, a Dahlquist LP 1 crossover, and a pair of used Kenwood L07 M amplifiers. In typical audiophile fashion went things are getting too hot you turn up the temperature. This was back in 1979 and I am still trying to get it right although I think I am very close, 95% of the way there. We had a lot of fun with the HQD system back in the day. Even though the Quads were crossed to subwoofers we blew them left and right giving demonstrations. I can still see Peter McGrath running back in the store room to come running back with a Quad on his shoulder, teeter tottering on a ladder replacing the upper unit. That people actually bought these things is beyond me. The Decca ribbon tweeter was even less reliable. I have no experience with modern quads because they are all point source speakers and I am a line source kind of guy. You might message skos and see what he thinks of the subwoofers and SLs. He has heard the system twice and is very opinionated. |
I never said it was a “theory”. But there is plenty of debate about its significance and audibility. The only reason it’s of particular importance for ESLs is because they tend to be full range or nearly full range sources. The best reason to use a subwoofer with an ESL is far and away relieving the main amplifier and the main speaker of reproducing extreme low bass frequencies, not because of Doppler distortion, in my opinion. Also, and with respect, you do tend to choose from a list of causes to explain a list of objectionable effects without much experimental proof of a relationship between the two. If you heard what you heard and it was fixed by adding a subwoof, that’s not proof you heard Doppler distortion. |
Dear @mijostyn : I refer to you because lew don't took in count my post to him, aniway here I come with you:
""" It is much less of a problem for two and three way speaker systems because the bass driver's range is limited. """
Not exactly " much less " because in a 2-way speaker normally its woofer goes from 50hz-60hz up to around 2.5khz and this kind of speakers ( its woofer ) goes down to 40hz even if you don't noted so there exist a really high IMD kind of distortions that subs relief the bass down there and midrange and HF shines as never before. Same with 3-way speakers.
We can't just stop the developed IMD that as you pointed out modulates/color the whole speaker reproduction. Maybe we don't noted because we already are accustommed to that color/modulattion but when we add a pair of self powered true subs and through high pass filters only a deaf audiophile can't hear that new and lowered distortions " color " with ( between others ) additional advantage that any amplifier will increment its headroom due that now is liberated of that main bass range.. If we like it the new " color " is not the main issue.
R. |
- 65 posts total