New Linkwitz "LX521" speakers..

As a sidenote... Recording engineers. How many of them listen to the live event only through headphones? How many really attend concerts and get out of their dead walls? Why should they be right, and us wrong?

To answer you questions, I only use headphones for tracking and QC, not mixing. I also have a season subscription to the San Francisco symphony, and attend quite a few jazz concerts every year.

We should be right because we are paid to be right. If we are wrong, then we would not have any clients. We mix and master the recordings you hear, so we know what they sound like BEFORE that has been done.


There is a chapter on Toole's book about reflexions. Engineers hate them, but listeners found them enhancing the experience. Do we work with sound or do we enjoy ourselves? If the goal is to reproduce what they had in mind mixing, all we need to do is get a pair of Genelec and a LEDE room. Is that the way to pure audio Nirvana?

When you are mixing, you don't need enhancements(reflections) - it hinders us from truely hearing what is on the file or tape. We need to hear the music clearly without a room tone to color it up.

I have not been in a single studio(and I have been in many) that used Genelecs are their primary monitoring system. I use Dunlavy's, ATC, and PMC's in my rooms. Now I do use Genelec's for creating tailored for HT film soundtracks.

Studio control rooms have gotten far more sophisticated acoustically than simple LEDE rooms. Keep in mind - a control room and your listening room have different functions, and different requirements.
 
if you are talking about CD only, maybe yes. Otherwise SL has played with various unpublished designs a while before that, the L-07 had rear tweeters and small mids to keep a good directivity back in the 80'.
The Audio Artistry line was dipole only til 1.5k, that was..15 years ago. :violin:
Sure, it's CD in this context that I'm referring to. I'm very aware of SL's designs, particularly the Audio Artistry range. I've been interested in dipoles for years and have the AES preprint of Celestion's work that led to the SL6000, for example. I think I have an AES preprint of SL's on dipoles too...
 
In addition you'll need big table in front of you below your nose to generate heavy midrange and treble comb filtering. And a swivel chair with wheels so your head is in constant movement and phantom image jumping all over the place.

All of the studios I have been in(including my own) have custom shaped acoustical panels surrounding the desk to obsorb those reflections.

When I am mixing, my head is not in constant movement - but my hands are. :D
 
We should be right because we are paid to be right. If we are wrong, then we would not have any clients. We mix and master the recordings you hear, so we know what they sound like BEFORE that has been done.

When you are mixing, you don't need enhancements(reflections) - it hinders us from truely hearing what is on the file or tape. We need to hear the music clearly without a room tone to color it up.

I was not saying you do a bad job, but we may well need a new paradigm.

As a pro, what would you recommend? Are you trully satisfied with the way music is usually presented?
 
I was not saying you do a bad job, but we may well need a new paradigm.

As a pro, what would you recommend? Are you trully satisfied with the way music is usually presented?

What people don't understand is we have far less influence on the final mix than the producers and marketing people have. That new paradigm would be that we do have the say so on the final mix - because we have created it.

Instead of mixing to get the best sound period, we are mixing basically for low rez sources like MP3 and radio. We are getting raw recordings that are far to hot, and lack any dynamics. Once it is like this, there is nothing one can do to make the recording sound any better. I personally will not work on a recording that has squashed dynamics. I have also quit doing work for the major labels as well - as once you finish a mix, you never know what it will sound like after it is mastered.

There is some light though. With so many mixing and mastering guys refusing these compromised recordings, we are starting to see things change. I just hope this continues, because things could not get worse than it had been.
 
Passive wide baffle OB

Has anybody had a chance to compare Martin's passive wide baffle OB designs to the ones by SL and JohnK. :confused:

Without resorting to brute force equalization to compensate for the dipole rolloff, Martin's designs are quite an elegant solution to full range dipole sound up until about 3KHz :)( that I believe can be radiated from the rear of 3-4" FR drivers, that Martin uses). Of course there is always an option to add a rear tweeter to Martin's OB designs, to further extend the dipole pattern.

Does the narrow panel OB have a distinct audible superiority over the wide baffle OB that has the immense advantage of no equalisation need and also passive crossover implementation is desired :p
 
Has anybody had a chance to compare Martin's passive wide baffle OB designs to the ones by SL and JohnK. :confused:

I have played with various wide baffles and cheap digital crossovers, one year of constant tweeking never brought me anywhere close to the Orions. It was fun though and an eye opener. once you switch to narrow baffles there is no way back..
 
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Does the narrow panel OB have a distinct audible superiority over the wide baffle OB that has the immense advantage of no equalisation need and also passive crossover implementation is desired :p

As already mentioned: if you're after well behaved dispersion up to higher up in frequency, then yes, a narrow baffle is better.

The "no equalisation needed and passive crossover" advantage of a wide baffle is a relative thing IMHO:

- if you use a relatively large midrange, say 7" (or an array, as I do), you can get away _without_ having to actively boost the lower midrange and still cross at 250-300Hz based on the natural roll-off of the midrange. You would only need a (passive) notch to equalize the dipole peak - easy to do and actually easier on a narrow baffle, because it happens at a higher frequency, thus no big bulky passive components needed (the lower you get, the more mH and uF you need).

- on the bass, you can use a passive circuit to boost the lower end - search for the T-Bass circuit of Graham Maynard here on the forum, it _really_ works great: I use one Eminence Alpha 15A per channel with no active boost down to around 40Hz in a shallow U-Frame.

- the one thing that might give you headache in a fully passive configuration, especially with a narrow baffle, is the sensitivity mismatch between bass and midrange, with the bass typically being lower. You can work around it by using more bass drivers, but I think at this point an active crossover is better (but not with brute force equalization). EDIT: or you use the hybrid crossover design approach of JohnK (passive crossover + active EQ to match sensitivities)

HTH
 
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I've done the big baffle OB system as well. 4 SLS woofers, SS 21W8554 mid, SB acoustic 29RDC tweeter. They are quite impressive, BIG image, totally different sounding that narrow baffle, "point source" dipole like SL's or my other speakers. Derived from my love of the Dayton Wright XG10 ELS, which I regret having ever sold.

An externally hosted image should be here but it was not working when we last tested it.


I really don't agree with the passive approach. The speaker above still requires considerable EQ in the bass region. It could be done passively but I feel that is just a waste of amp head room. Hybrid or all active makes more sense to me.
 
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I really don't agree with the passive approach. The speaker above still requires considerable EQ in the bass region. It could be done passively but I feel that is just a waste of amp head room. Hybrid or all active makes more sense to me.

That's a consequence of the woofer choice. With low-Q, high excursion woofers like SLS you're "stuck" with active boost (not that it is a bad thing) and doing it passively is a waste as you say.

Passive is only practical if one _doesn't_ have to do huge amount of EQ. Things are different with large diameter (15"+), higher sensitivity, middle-to-high-Q woofers, those do not require as much EQ.
 
High Q 15" woofers

High Q, 15 inch woofers like the very inexpensive Eminence alpha 15, Goldwood 15" and in the price range of SEAS L26ROY the Acoustic Elegance dipole 15 offer flat bass as low or lower than 40Hz in passive OB designs without equalisation active or passive.

John, if you have bought into Geddes's idea of no difference b/w dipole and monopole bass, do you plan to do away with your cardioid woofer designs for the Nao speakers !
 
I've done the big baffle OB system as well. 4 SLS woofers, SS 21W8554 mid, SB acoustic 29RDC tweeter. They are quite impressive, BIG image, totally different sounding that narrow baffle, "point source" dipole like SL's or my other speakers. Derived from my love of the Dayton Wright XG10 ELS, which I regret having ever sold.

NaO_DW.JPG


I really don't agree with the passive approach. The speaker above still requires considerable EQ in the bass region. It could be done passively but I feel that is just a waste of amp head room. Hybrid or all active makes more sense to me.

Now that is a relatively "clean" aesthetic.. (..I'm a little less partial to the old-school fabric and wood choice however. Still, it does have some nostalgia going for it - reminds me of my grandfather's old large Bozaks..)

What's the width and height?
 
High Q, 15 inch woofers like the very inexpensive Eminence alpha 15, Goldwood 15" and in the price range of SEAS L26ROY the Acoustic Elegance dipole 15 offer flat bass as low or lower than 40Hz in passive OB designs without equalisation active or passive.

John, if you have bought into Geddes's idea of no difference b/w dipole and monopole bass, do you plan to do away with your cardioid woofer designs for the Nao speakers !

Well, I am going to a dipole woofer on the revised Note II Rs, but no, I am not planing on changing the designs at this point. After all, they still represent multiple sources with different position and phase. The point being that dipoles and cardioid are multiple sources and that is a good thing. If you have followed the history of the NaO II you well recall that it had cardioid woofers which could be converted to monopoles (for increased max SPL capability). But it always sounded better in cardioid mode. The arguments for that were always based on how cardioids couple to the room. while that isn't wrong, when you look at the cardioid (or dipole) as multiple sources the reasons become clearer.
 
Posted today on SL's website

"The shape of the midrange/tweeter baffle is the result of acoustic requirements, as is the woofer baffle. They are angular and not hidden behind grill cloth. The acoustic impedance of grill cloth rarely matches the acoustic field impedance near the radiator, causing frequency dependent reflection and transmission loss, which can also be angle dependent. The LX521 is meant to be used without grill cloth with the exception of a light fabric table runner over the woofer baffle to partially cover its front and rear openings."

I don't think grill cloth will impede performance that much.