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Where does the money in expensive speakers get spent?

finkaudio said:
Sorry, no. At 1k, you will not see tuning effects. However this is a simulation of a front baffle with 22cmx36cm and a 6.5" driver sitting at the usual position without any parameters. Just the acoustic load of the baffle This hump is the diffraction effect, indeed. There is not a lot you can do with a 6.5" driver on such a baffle.:p

I use this little simulation tool a lot and I always compare the results with measurements. It shows me how much I have to do about the hump and what is the pure baffle step. If I have more space on the front baffle, I can reduce the hump by moving the driver around, but with a classic 2-way bookshelf, it's difficult.

Best regards
KH
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Yes, I thought it was diffraction. The only way to reduce the effects at any particular frequency seem to be with some driver offset on a rectangular baffle, although this can affect lobing if too extreme which needs consideration. I've used 12mm thick (shaped) acoustic wool felt before now but prefer not to do that if possible. The narrower the cab, especially when using offset tweeters, the less of an issue it appears to be. Shaped front cabs are something I'm playing around with for a new 3 way design, but as with all these things, optimising cab design = greater expense at manufacture.

Simulation tools are a godsend. I'm constantly impressed by just how close simulation can get to actual measurement, given you feed the sim tool with measured impedance and acoustic (raw) data. I know that some use library data but I (I presume, like yourself) like to use measured data with the drivers in the cabs, imported back into the sim software.
 
I've mentioned this before but the Westlake cabinet construction is probably the least intrusive I have heard. I could not detect any cabinet colouration at all.

I know that they apply a coating of an acoustic putty like paint prior to two layers of damping internally but have never discovered the compound that they use. I did some research some years ago but have lost the links.

Traditional wooden cabinets in many ways but the best I have heard.
 
The single greatest advance has been in terms of the sophistication of simulation software. However, as ever, the results are only as good as the data inputed and the subsequent interpretation of the output - the models don't tell you which parameters are more important than others or scale them to human perception.
 
Built these actives with amplification and wired for just under 5K CND. From planning to playing music, about month. They sound amazing.
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....yes, moving drivers around can help, but in a real world speaker with a narrow baffle we have no chance. However, I just wanted to show that baffle step compensation with the lowpass filter is tricky. A simple LCR with 4mH, 6-10uF and 6-12 Ohm in parallel with the woofer will fix it and opens the door for a good balance.

Best regards

KH
 
finkaudio said:
....yes, moving drivers around can help, but in a real world speaker with a narrow baffle we have no chance. However, I just wanted to show that baffle step compensation with the lowpass filter is tricky. A simple LCR with 4mH, 6-10uF and 6-12 Ohm in parallel with the woofer will fix it and opens the door for a good balance.

Best regards

KH
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Personally, if measured results showed under say 1.5dB peak at baffle step, I'd probably be more concerned about adding in unnecessary complexity of a notch filter as the room itself is likely to have a more profound effect (assuming of course that initial measurements were not with speakers in final locations), but granted it's one way of dealing with the issue.
 
Pac1 said:
Personally, if measured results showed under say 1.5dB peak at baffle step, I'd probably be more concerned about adding in unnecessary complexity of a notch filter as the room itself is likely to have a more profound effect (assuming of course that initial measurements were not with speakers in final locations), but granted it's one way of dealing with the issue.
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..it all depends on the project. 1.5dB at 1 kHz can be a bit too much. But there is another problem: To compensate without extra components, you need to increase the inductor and sometimes this takes away too much energy in the crossover region. We normally compensate Le over excursion and that means the level does not come up again due to flatter impedance.

Best regards

KH
 
finkaudio said:
..it all depends on the project. 1.5dB at 1 kHz can be a bit too much. But there is another problem: To compensate without extra components, you need to increase the inductor and sometimes this takes away too much energy in the crossover region. We normally compensate Le over excursion and that means the level does not come up again due to flatter impedance.

Best regards

KH
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Absolutely agree. FWIW, I do the same thing, and with some drivers it's possible to achieve with slightly increased inductor values then with some modest resistance in series with bass shunt caps rather than adding a separate Zobel. Testing speakers in for refurb, I often find that a surprising number of speakers achieve optimistic efficiency/sensitivity through doing the opposite and often sound mid-forwards as a result, carrying too much energy into the crossover region.
 
EJJordan Design said:
Hi - One of the PFM regulars asked us to add to the discussion about the Eikona and I'm alway happy to add any info (within my technical limits - I'm not Ted).

The JX92S in particular had a peak at HF due to a resonance in the dustcap, something which was addressed with the pole piece in the original Eikona and again with the Eikona 2. The peak is clear on the measurements but not obvious on listening. A broader, more general trend would be more audible.

Regarding toe-in - this is something Ted has always recommended for all his speakers. It is to do with the Haas effect and maintaining a stable stereo image away from the centre line between the two speakers. As you move off-axis from the nearer speaker, you move on-axis on the one farther away. This compensates for the increased volume from the nearer speaker and keeps the image stable. It is something he and others researched in the 1960s and 70s.
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Hi. I've only just noticed this post! Although, as Ted says, the central image is more stable and wider with more toe-in, I have consistently found the image depth and general soundstage to suffer. This remains true with many different speakers, so I prefer to point mine more forward and suffer the reduction in "sweet-spot" size. Unfortunately with Ted's speakers this brings the HF peak back up. My last set up used the JXR6 and JX125NG drivers, driven actively, which still suffered from some of the same problems. I went passive (my wife had problems using the active system) and now have a different set of problems. I don't really like passives, but I'm stuck with them for the sake of domestic harmony. :mad:
I had a pair of the early JX92s (which I bought direct from Ted) which didn't have a dustcap, just ring of epoxy holding the suspension rod. I wish I could have afforded to keep them, but it's one in, one out here!
 
Hi Awkwardbydesign - thanks for giving me the opportunity to clear up something important re Jordan speakers. When production transferred outside Europe, the licence to use the Jordan name and designs passed to another company, who continued to manufacture modified versions of the JXR6 and JX125 (named the JX125NG). The technical performance wasn't to Ted's liking so he withdrew his name from them and they are no longer branded as Jordan.

HF peaks sometimes serve to extend the HF response over 20kHz and make the FR graphs look more impressive, something Ted refuses to do (measuring 10 degrees off axis smooths the apparent response, something else he doesn't do). The Eikona goes to some lengths to avoid harshness at HF.

Regarding active - have you looked at the Hypex and MiniDSP plate amps? They offer a neat solution. With a suitable preamp the system becomes as straightforward to operate as a conventional passive plus amp.
 
EJJordan Design said:
Hi Awkwardbydesign - thanks for giving me the opportunity to clear up something important re Jordan speakers. When production transferred outside Europe, the licence to use the Jordan name and designs passed to another company, who continued to manufacture modified versions of the JXR6 and JX125 (named the JX125NG). The technical performance wasn't to Ted's liking so he withdrew his name from them and they are no longer branded as Jordan.

HF peaks sometimes serve to extend the HF response over 20kHz and make the FR graphs look more impressive, something Ted refuses to do (measuring 10 degrees off axis smooths the apparent response, something else he doesn't do). The Eikona goes to some lengths to avoid harshness at HF.

Regarding active - have you looked at the Hypex and MiniDSP plate amps? They offer a neat solution. With a suitable preamp the system becomes as straightforward to operate as a conventional passive plus amp.
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I bought the JXR6s directly from Ted, so I presume they were to his design!
I have an analogue active crossover I built over 30 years ago. http://www.saturn-sound.com/images ...rossover - hi-fi news - february 1981 - 1.jpg
It's been upgraded considerably over the years, but I have a tendency to crash motorbikes at high speed, so my wife wanted a simpler system in case I die! :eek:
My hearing has a (measured) rising response, so I am particularly sensitive to things like sibilance, which makes life difficult, especially at the prices I can afford. Ribbons, planars and electrostatic (I still have Shackman panels) HF drivers seem to suit me, but they are generally difficult to implement. Or afford!
 
Audio Images said:
the money we make from selling expensive loudspeakers gets spent in the pub
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Ha! :)

Having read some of the helpful responses and interesting digressions I realise there is a huge amount of time required in order to get this right. I had no idea about driver pairing and phase corrections, plus the depth of consequences involved in the choices made. I'm very grateful to have been able to benefit from some such qualified contributions.

It all seemed so simple to start with. I still value the amp over the speakers but I'm really glad progress is still going on and I still want those silly money speakers I didn't manage to win recently on eBay! Speaker building is like the science of meteorology!

I'm gonna spend some money I didn't want to save down the pub.
 
I've had a rare afternoon of listening to very expensive two ways at realistic levels.

We were reading an interview with Bruce Swedien where he was relaying the information that he typically listens and mixes with peaks of 90db at the chair. Also reading how he relies on Westlakes for these duties.

So I cranked up the system to peaks of 90db for a change (usually a lot quieter than that). The extra money on these speakers goes primarily into driver design and fabrication that results in vanishingly low distortion at realistic levels. And boy can you hear it at those levels.

Speakers that just go loud rather than sounding loud cost money IME.
 
Would you care to say what they were? I'm always fascinated to learn how much can be squeezed out of a two way.
 
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