Here you are Vifa 10 BGS.
It looks like we cannot judge by using CSD which driver is more detailed or we should measure at -60dB? For example an old Audiovector M1S which is a typical polypropylene minimonitor based on Vifa drivers.
I've found Manger very natural, Alexandar from RAAL ribbons thin and without body. That's a mystery for me. Without any doubt his ribbons has the cleanest impulses so far.
Mangers
I used these for a few years. They sound far better than the Jordans, but have their own issues. Low SPL capability, high frequency extension that is seriously lacking, beaming, POOR off axis response, and ultimate difficulty mating ANY cone driver to them for low frequency extension.
This was my experience,
C
I used these for a few years. They sound far better than the Jordans, but have their own issues. Low SPL capability, high frequency extension that is seriously lacking, beaming, POOR off axis response, and ultimate difficulty mating ANY cone driver to them for low frequency extension.
This was my experience,
C
When I was at Herr Manger house in June he used holoprofile reflectors and bipolar firing - no problem with high frequencies and beaming. Everywhere the picture was the same and very good, natural (he is active in recording field as well). The sound was quiet indeed even at max volume possible on modified Sony XA-50ES and class A power amplifiers with 500KHz bandwidth. Maybe it is a lack of "transient noise"?
I don't understand low frequencies - many people complains that Manger is hard to mate on bass, others says that low mass rigid aluminium drivers like Bandor 150 are imprecise in low frequencies. What we are looking for?
I don't understand low frequencies - many people complains that Manger is hard to mate on bass, others says that low mass rigid aluminium drivers like Bandor 150 are imprecise in low frequencies. What we are looking for?
thomaseliot said:
Hmm, I'd like to take you up on that. I don't know anyone in Italy, and unfortunately, I haven't gotten any phone call or or e-mail responses from a US importer, Loudspeakers Plus. More than a week has gone by - either they're on vacation or ... ?
I'd particularly like the know the suitability for the highest-quality midbass application of the 12ND710, the 12NDA520, or the 8NMB420. Smooth time-decay characteristics in the 1~5 kHz range and low IM distortion in the 200 Hz ~2 kHz range are a priority.
I'm also curious which of the 15" drivers would have the lowest distortion in the 80~400 Hz region while avoiding severe resonances in 1~3 kHz region. Lots of questions here, and not all the answers are on the 18Sound website.
Hi nullspace, I might be contacting you some time in the fall, after the RMAF, especially if there aren't any Fertins to audition at the show. I'm OK with paying shipping, it's a lot cheaper than buying them outright - what kind of price do the drivers go for in the USA, anyway? Haven't seen much info on this. I'm guessing Lowther or AER prices.
Sorry about the cranky tone of postings about the mainstream audiophile driver vendors. When I designed the Ariel in the 1991-94 timeframe, I was content to think that drivers would gradually improve in efficiency, have better time-decay characteristics, and sound better as the decades rolled on. Based on that expectation, I thought it would simple to one day upgrade to a "Super Ariel" with better, more efficient drivers. That had been the pattern over the past decades, and I expected it to continue.
Quite a lot of time has gone by - the same as between the inefficient old-school KEF and Audax Bextrene drivers and the best of the late-Eighties polypropylene drivers - and I have frankly been very disappointed. There's only been a trivial gain in efficiency despite more than a decade of "please please please" from many loudspeaker manufacturers, the founders of the old-line Scandinavian manufacturers have all left, and worst of all, a lot of the drivers are now made in China, with typical Chinese quality control, while keeping European prices! I'm not at all surprised the Chinese have figured out the smart thing to do is bypass the "talent" of the European design houses and sell directly to OEMs and hobbyists.
Imagine what would happen if Mercedes-Benz and BMW started to outsource both design and manufacturing to China - how long would they stay in business before the Chinese did the smart thing and undercut them in their own market? Same for boutique drivers. The founders, their children, and the old engineers have left, the new owners and new engineers are still finding their way, and manufacturing is moving overseas. If all that's left of Scan-Speak, Vifa, Seas, et al is a name and a logo, why bother?
If I liked the sound of modern audiophile speakers, well, I could overlook all that. But I don't - and the low efficiency and consequent need for a 200-watt transistor amp rules them out of consideration anyway. Thus, the move to prosound, and more esoteric "studio-monitor" driver market.
Quite a lot of time has gone by - the same as between the inefficient old-school KEF and Audax Bextrene drivers and the best of the late-Eighties polypropylene drivers - and I have frankly been very disappointed. There's only been a trivial gain in efficiency despite more than a decade of "please please please" from many loudspeaker manufacturers, the founders of the old-line Scandinavian manufacturers have all left, and worst of all, a lot of the drivers are now made in China, with typical Chinese quality control, while keeping European prices! I'm not at all surprised the Chinese have figured out the smart thing to do is bypass the "talent" of the European design houses and sell directly to OEMs and hobbyists.
Imagine what would happen if Mercedes-Benz and BMW started to outsource both design and manufacturing to China - how long would they stay in business before the Chinese did the smart thing and undercut them in their own market? Same for boutique drivers. The founders, their children, and the old engineers have left, the new owners and new engineers are still finding their way, and manufacturing is moving overseas. If all that's left of Scan-Speak, Vifa, Seas, et al is a name and a logo, why bother?
If I liked the sound of modern audiophile speakers, well, I could overlook all that. But I don't - and the low efficiency and consequent need for a 200-watt transistor amp rules them out of consideration anyway. Thus, the move to prosound, and more esoteric "studio-monitor" driver market.
Lynn Olson said:
Last time I saw, they were upwards of $2k per pair with options like silver voice coils pushing them over $3k. The NA distributer, Gilles Gagne, posts on diyAudio as 'lrntglls', so perhaps he'll enlighten as to the latest pricing. I lucked out and snagged a 'gently used' pair a couple of years ago at a substantial discount.
I will add that I have an earlier pair and that supposedly the vintage they're selling now is different, so if you're looking for strictly current production mine might not be the best proxy but the offer stands in any case.
Regards,
John
Lynn Olson said:
Have to agree with you there. Some of the newer Peerless drivers are "Designed in Denmark” and apparently made in China. I have had a number of them and the first (early production) set was made in Denmark and were excellent. The next set was early production from China and they measured significantly different. When I contacted Peerless (or Tymphany, the new parent company) they were very interested in the difference and sent me a matched set of replacements which were now different again form any of the previous drivers. All had visibly different construction at the VC former/cone junction. Also of interest was the price increase with Chinese production.
I looked at the CSD for the Vifa 10 BGS and think it's pretty close to Jordans, I can't really tell because I normally look at the first 0.4 ms while most data show 4ms or so without enough resolution.jzagaja said:
I have not measured Mangers, but first listening impression was that some detail was lacking. This is possibly due to the large but soft diaphram where multiple modes exists to some extent even though they are well damped. But I would have to measure myself to be sure.
I think if you go to higher SPLs, the Mangers may not be able to move enough air to be compatible with woofers, thus the need to cross over at higher frequency, which I would guess 450Hz would be good.jzagaja said:
Low mass aluminum drivers are really very complicated to tune. Having examined some Bandors and used Jordan JX125, I think the the cone shape and material stiffness needs to be adjusted a little to get a better balance. This is one thing I hope will happen with the Jordans through the new company.
Hi Lynn
Its been years since I sampled any hifi drivers while I look through Madisound frequently. Frankly, it would appear that many drivers are designed for appearance and technical appeal as a well as function.
I do sample a lot of pro sound drivers however and since what I do is try to design speakers with hopes of the hifi experience for a crowd, have some thoughts which might be applicable here.
Although to be honest, I have never built an open baffle speaker before other than electrostatic panels.
Many of the things that are wrong with drivers, get worse much faster than the level increases. As a result “headroom is your friend”.
A bad sign (regardless of cone material) for a direct radiator is a large peak(s) associated with its hf roll off. It is assumed that a steep or low crossover fixes this problem but it is not gone. So, picture a driver with a big mound in its response associated with breakup.
Lets say that mound is 10 dB high above the “flat” response zone, this represents an frequency dependent acoustic gain element AFTER the voice coil.
So, here is where it is not fixed even with a brickwall crossover.
The driver’s motor produces harmonic distortion, that acoustic gain amplifies it by 10X (10dB) for harmonics when the fundamental is N fraction of the peak.
In other words, if the mound were at 1200Hz, the third harmonic of a fundamental at 400Hz is amplified by the acoustic gain even if one had a 120,000dB / octave digimatic crossover at 500Hz. Here it is better to fix the source.
Exotic materials are more commonly known for “those” kinds of peaks because the focus is usually on strength to weight and not damping.
The best radiator material is the best trade off of all the requirements and it is still very hard to beat paper processed fibers. You inclination to look there is I think a good one.
It would be nice if mfr’s of pro sound speakers had more information, it would be nice if they all had the same rulers so far as Watts and dB. You would not believe what kind of BS goes on, there are small speakers, which claim peaks of 148dB! (Possible only with a lightning strike directed to the speakers terminals). It makes selling products in that industry a weird business. Fortunately many folks can measure and do side by side comparisons too.
For the person looking at prodrivers though it is much better, most have at least a response curve and you know that if they have peaks and bumps, they will have trails in the csd.
At work, I use drivers made be B&C, BMS, Belisle, 18Sound and have some made to spec by Eminance, Celestion and Misco. All of them make very good devices.
So far as distortion, speakers change with different with frequencies and levels, it is hard to quantify that many dimensions.
In general, what I find is that if you run a driver at –30dB from where it is distorting, it is pretty well behaved. This would be 1/1000 rated power.
Starting at about 1/10 to 1/8 of a drivers rated power, power compression will begin to alter the drivers parameters / response. The time constant for this effect (reduction in SPL compared to ideal driver etc) is VERY short for most tweeters, and reaches ten’s of seconds for a large woofer VC.
Also, when you exceed Xmax, distortion skyrockets.
For dynamic linearity and harmonic distortion, headroom is your best friend.
Anyway, some thoughts, the dogs are clawing through the back door, don’t want an accident.
Best,
Tom Danley
Its been years since I sampled any hifi drivers while I look through Madisound frequently. Frankly, it would appear that many drivers are designed for appearance and technical appeal as a well as function.
I do sample a lot of pro sound drivers however and since what I do is try to design speakers with hopes of the hifi experience for a crowd, have some thoughts which might be applicable here.
Although to be honest, I have never built an open baffle speaker before other than electrostatic panels.
Many of the things that are wrong with drivers, get worse much faster than the level increases. As a result “headroom is your friend”.
A bad sign (regardless of cone material) for a direct radiator is a large peak(s) associated with its hf roll off. It is assumed that a steep or low crossover fixes this problem but it is not gone. So, picture a driver with a big mound in its response associated with breakup.
Lets say that mound is 10 dB high above the “flat” response zone, this represents an frequency dependent acoustic gain element AFTER the voice coil.
So, here is where it is not fixed even with a brickwall crossover.
The driver’s motor produces harmonic distortion, that acoustic gain amplifies it by 10X (10dB) for harmonics when the fundamental is N fraction of the peak.
In other words, if the mound were at 1200Hz, the third harmonic of a fundamental at 400Hz is amplified by the acoustic gain even if one had a 120,000dB / octave digimatic crossover at 500Hz. Here it is better to fix the source.
Exotic materials are more commonly known for “those” kinds of peaks because the focus is usually on strength to weight and not damping.
The best radiator material is the best trade off of all the requirements and it is still very hard to beat paper processed fibers. You inclination to look there is I think a good one.
It would be nice if mfr’s of pro sound speakers had more information, it would be nice if they all had the same rulers so far as Watts and dB. You would not believe what kind of BS goes on, there are small speakers, which claim peaks of 148dB! (Possible only with a lightning strike directed to the speakers terminals). It makes selling products in that industry a weird business. Fortunately many folks can measure and do side by side comparisons too.
For the person looking at prodrivers though it is much better, most have at least a response curve and you know that if they have peaks and bumps, they will have trails in the csd.
At work, I use drivers made be B&C, BMS, Belisle, 18Sound and have some made to spec by Eminance, Celestion and Misco. All of them make very good devices.
So far as distortion, speakers change with different with frequencies and levels, it is hard to quantify that many dimensions.
In general, what I find is that if you run a driver at –30dB from where it is distorting, it is pretty well behaved. This would be 1/1000 rated power.
Starting at about 1/10 to 1/8 of a drivers rated power, power compression will begin to alter the drivers parameters / response. The time constant for this effect (reduction in SPL compared to ideal driver etc) is VERY short for most tweeters, and reaches ten’s of seconds for a large woofer VC.
Also, when you exceed Xmax, distortion skyrockets.
For dynamic linearity and harmonic distortion, headroom is your best friend.
Anyway, some thoughts, the dogs are clawing through the back door, don’t want an accident.
Best,
Tom Danley
Tom Danley said:
Thanks, JohnK and Tom, your comments, along with all the others, are always appreciated, even if I sound a little cross at times - I've been going through a little medical hassle the last month, and it does affect my mood at times. It appears to be going away on its own, thank goodness.
As the previous posts indicate, I was once very pleased with the Scandinavian family of drivers. But I really feel with the changes in ownership and the loss of the original engineering crew, they've lost their way, which has had a negative effect on the entire high-end speaker industry. I see a gradual decline in musicality, more emphasis on gimmicky cones and tweeters, both of which reflect a loss of continuity in management and engineering.
The join between the VC and the cone might sound like a tiny thing, but it isn't - this region has a dramatic effect on the sound, and measurements, of the driver. The acceleration forces reach their maximum in this tiny region, and it has to remembered the VC itself is a parasitic mass that doesn't (and shouldn't) radiate any sound at all.
If the speed of sound between the cone and VC former is different (and it will be if they're made of different materials), a mechanical reflection is set up between the two, right at the angled bend at the base of the cone. This reflection then sets up additional resonances in the spider and adjacent dust cap. The seemingly minor choice of construction materials (glues) in this area has a critical effect on the sound of the entire hifi system. To "overlook" this part of the driver is like delivering a car without a steering wheel or a transmission.
I now fully agree with Tom about the many benefits of high-headroom design. I used to be in the audiophile camp, but I think audiophile driver design has reached a dead end, and we'll be seeing more progress in the prosound arena. The exotic prosound cooling techniques have an interesting payoff for audiophiles, because it greatly reduces the time constant for the VC to cool itself - this a good thing! Remember, even with ultra-efficient drivers, more than 90% of those costly amplifier watts make no sound at all, but merely heats the tiny voice coil - which then has to be cooled as quickly as possible.
The distortion reduction aspect, combined with a huge improvement in headroom, is the greatest, most audible benefit of all. In home use, the driver will never approach its true limits - this takes us back to the kind of headroom that hifi enthusiasts enjoyed back in the Fifties, when the movie theater and consumer world were closer together.
A subtle downside to high-headroom truly efficient drivers is they reveal the truth about high-power Class AB transistor amplifiers - they don't sound all that good in the milliwatt region. In the pro world, it doesn't matter that much, since we're talking about kilowatts anyway, and in the audiophile world, the "exotic" speakers are such power sponges the amp never gets into the low-power region for long. The dramatically lower distortion of high-efficiency speakers reveals a lot more about amplifier sonics.
Hey Lynn,
Looks like my Buddy John B. will be at RMAF. Not as an official exhibitor, just a "cowboy." John has been building O.B. speakers with pro drivers for many years.
The main rig he will bring sounds a lot like what has been discussed here.
Four twelves + a tweeter per side on a flat baffle. AFAIK, it will go like this:
Bass. 3x12" Old Eminence auto subs that use a magnet structure from 18s . Big, very heavy thumpers that move plenty air.
Mid. 1x Beta 12LTA. (Old style, small x-max). Used for great dynamics and tonal balance.
High. 1x dome tweeter. A SEAS, I think. Easy to crossover to the BetaLTA.
It will be a passive crossover, John is the King of crossovers. Might be bi-amped, not sure. I doubt it will be as refined as what your are planing with the BTA, but will certainly be similar in concept. Certainly worth your time for a listen and look. I sure look forward to hearing them.
Looks like my Buddy John B. will be at RMAF. Not as an official exhibitor, just a "cowboy." John has been building O.B. speakers with pro drivers for many years.
The main rig he will bring sounds a lot like what has been discussed here.
Four twelves + a tweeter per side on a flat baffle. AFAIK, it will go like this:
Bass. 3x12" Old Eminence auto subs that use a magnet structure from 18s . Big, very heavy thumpers that move plenty air.
Mid. 1x Beta 12LTA. (Old style, small x-max). Used for great dynamics and tonal balance.
High. 1x dome tweeter. A SEAS, I think. Easy to crossover to the BetaLTA.
It will be a passive crossover, John is the King of crossovers. Might be bi-amped, not sure. I doubt it will be as refined as what your are planing with the BTA, but will certainly be similar in concept. Certainly worth your time for a listen and look. I sure look forward to hearing them.
Tom Danley said:
I couldn't agree with you more. This is one rerason I particualrly don't like metal cones. The SEAS Excel metal cones, for example, have very smooth and very linear frequency response up to the point where the breakup comes in. And to me the audibility of the effect of the breakup, distortion or otherwise, are clearly audible with the crossover in place. Door bells and tuning forks should ring, not driver cones.