Oh, you never mentioned that in the original post...a pair of X's mini Ks or TABAQs would make pretty honest monitors, with a helper sub...
When the multiple drivers are spaced farther than about 1/3rd or 1/2 of the wavelength that they play, it can sound like distinct different sources. That’s why multi-way speakers (unless coaxial or Synergy like) can sound like multiple units and lack the coherency of a single full range. On an amplifier with multiple output devices the effect is different - more of current sharing mismatch than different “voices”. The speed of light over inches of wire is so fast that time delay is not an issue. Whereas speed of sound is significantly vs driver spacing.
Hey X, you know how you perceive multiple amplifier output devices causing "single voices to sound like a choir" (I paraphrase)is there a similar effect with multiple drive units?
I hadn’t seen that before, but it is something i have been saying (with different wording) since the late 70s. I like the phrasing.
Multiple drivers will have teh same issue. They also have the added problem of physical distancing.
Unless devices can be perfectly matched (not really possible, one will get lower DDR as the low level stuff gets averaged out by any differences.
How much the effect bothers the listener, will be very dependent on the listener.
dave
He's dead and I don't have a ouija board.
I have his preamp cookbook (somewhere in storage along with my Sound Practices issues).
After googling DDR as Downward Dynamic Range I came up with this:
Downward Dynamic Range - a fuller description. - Allen Wright - Vinyl Asylum
It's exactly as I described. And I did a much better job of it.
As for Downward Dynamic Range: it NEVER CAUGHT ON:
1. "Low Level Detail" was in use before then and did.
2. It's not a particularly good description.
"DDR" as an acronym exponentially creates less understanding of what's intended to be conveyed.
I don't mind if you want to use the term, but each time you use it (for the sake of any reader who might read it) needs a good explanation. ..and a bit of objective evidence wouldn't hurt either.
Really all you would need to do is create a hypertext link with DDR to your own Diyaudio article on it specifically in respect to loudspeakers/drivers. ..dido for "WAW".
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It's a linear effect as opposed to a non-linear effect relating to the driver's objective performance.
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I understand the concept (DDR); whatever you want to call it. I know I keep bringing this up but one of the MANY reasons I like the MA P7PHD so much is that it lives up to it's name of HD (high definition). This means, among other things, it is very good at presenting low level details and high level details simultaneously. I have heard many other drivers that just simply cannot do this; they mask or smear or even completely "ignore" the finest details, nuance, whatever term you choose to use; especially with complex signals on the very finest of recordings. To repeat; the P7PHD purposely rolls off the high end but this is way more preferable than a falsely exaggerated and extended top octave. Most every full-range driver has compromises; the P7PHD compromises suite my listening habits and preferences more so than any other FR, extended-range, etc. driver in my experience and opinion. Ah yes; it is, after all, coming back to PERSONAL TASTES (very subjective; sometimes very controversial...)...FWIW, my 2 cents once again...
Mine are pretyt much broken in now, jus have to figure out how to get the FH3 upstairs (gimped left foot means heavy stuff difficulat to hump).
The infamous CHN70, while having been voiced for the Japanese as well, also did DDR well, but it got heavily scathed for its non-flat response.
dave
Get some help or helpers; I have the same issues...back, knees, ankles and hips ALL give me fits; some days worse than others. I would love to see some 3rd party testing of the P7PHD soon. The OEM FR plots show the roll-off starting at about 5 KHz. I think it starts higher than that and I also think the roll-off is not nearly as severe as shown. As I have said elsewhere; my mid. 60's hearing is GREATLY attenuated above 10 KHz but in doing listening tests, I could detect significant output up to about 15 KHz using test tones, sweeps, etc. I no longer have an SPL meter or calibrated microphone to do my own measurements but if "I" can hear 15 KHz from these; "YOU" and others may decide this are still worthy of being known as full-range!??
Well, since the delay, phase related issues of two widely separated (relative to frequency) drive units playing the same signal are well known and understood, and have been for about 9 decades, not much to see here, n'est-ce pas? Hence the reason that if two identical drivers playing the same frequency are to behave acoustically like a single source, they need to be acoustically close relative to the highest wavelength they are expected to play. In the case of a multiway, that includes the transition band, and potentially part of the nominal stopband also depending on transition frequency & order. Arrays function under different conditions that vary with specific type (nearfield, focussed, CBT et al) so require treating somewhat differently.
Hence the reason that if two identical drivers playing the same frequency are to behave acoustically like a single source, they need to be acoustically close relative to the highest wavelength they are expected to play. In the case of a multiway, that includes the transition band, and potentially part of the nominal stopband also depending on transition frequency & order. Arrays function under different conditions that vary with specific type (nearfield, focussed, CBT et al) so require treating somewhat differently.
Pass, I'm talking about loudspeakers, as Dave was. 'can't comment about multiple amplifiers & active filtering; I've no real interest in that side (passive filters & speakers are my thing), nor have I experienced the effect that apparently you and X have with my modest exposure to such systems. To my mediocre mind however, it sounds more like something related to implementation than general type.
Just like two microphones co located, when considering time based, absolutely. And those phase differences can be so far apart as to result in deep nulls which is often the case with Arrays....often referred to as comb filtering. But everything is relative to time and distance....NEITHER of which are your friend in the nearfield so hence my quest here......a single wide band point source for critical analysis and faster workflow.
Looking like i’ll have to spring for the big bucks and the ScanSpeak 10F LOL
Perhaps he was, I don't know, it seemed he was saying the issues were the same, maybe he will clarify?
My question to X (which he understood) was about multiple amplifier output devices, for example, parallel transistors.
Maybe he (as in Dave) will, re your speculation about whether he will clarify. I was merely stating that as far as drive units are concerned, he, X and others are absolutely correct. Output devices & amplifiers I leave to those qualified to speak on the subject, although to me, you'd need a heck of a disparity. Not a subject I have any particular knowledge about however, and zero engagement with.
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