Oh goodness I was just trying to be funny.
Hardly a fanboy. Not using any PSA stuff at all.
Bringing them to Axpona?
So, the Piega designs appear nice and I like their youtube videos where they show the care that they use in crafting their coaxial driver. However, I haven’t spent any time with them.
I had a good amount of experience in planar drivers. Growing up, my father had a speaker company, Speakerlab, in the Seattle area. The engineer there, David Graebener, developed the original Carver Amazing Loudspeaker with Jim Croft and later refined that design at Speakerlab for a few years in the early 90’s. David later went on found Bohelnder Grabener (BG). Paul and Arnie used both the Carver and BG planar ribbon midranges in their large array speakers at Genesis. The midrange in Arnie’s “IRS Killers” prototypes was acutally one of the single-sided 24" units from American Techology Corporation. This effort (at ATC) was to get into OEM car audio and this was licensed to Harman and some of the ~8" units actually made it into a couple of cars. I worked at BG as an engineer and project manager for 5 years from 2005-2010 after David’s departure from the company, with Igor Levitsky. Igor developed the planar drivers for HiVi research, SLS Audio / Dolby, BG, Christie Viive audio and the planar magnetic headphones for Oppo and is now doing things for Radian and I learned a lot from my father, David and him about them.
I took the BG NEO10 design which was truly a fantastic midrange but is now nearly 15 years old and I used a new corrugation technique and higher strength magnets to improve the performance. We now have about 3 dB more sensitivity and even lower distortion. This mid plays down to as low as 250 Hz in singles and 150 Hz in arrays and is really fun to work with as a designer, in this newest incarnation.
If I were to clamp it in the center, as Piega did, I would lose at least an octave on the low end because of the higher resonance caused by the much narrower diaphragm and I think that covering even more of the vocal range with the unit is more important. I believe that Piega is crossing over in the 700-800 Hz range.
This coaxial concept was part of a design that i worked on with Igor at BG and Allen Boothroyd of Meridian and I have further evolved that concept to get something that, when released, we can be really proud of.
The trick with the perforation is the have it act as a solid baffle (from a diffraction standpoint) for the tweeter, but be acoustically transparent to the midrange behind it. The distances of the grille relative to the mid is such that any interference is 2-3 octaves above the crossover point and is inconsequential. Again, it comes down to the wavelengths of the sound in question. The net benefit is broad and symmetrical coverage without the lobing issues of no coincident sources. Very wide horizontally and slightly more controlled vertically, as is the ideal, but with the dynamics and impact of a larger midrange.
You don’t have to take my word for it and this will be proven out in the published measurements and subjective performance of the units but this is the concept in a nutshell.
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Yes, this is one of those finish issues with these sample images that I mentioned. We had requested matte and they were mistakenly made in a gloss We also had a couple of different materials / finishes that the grilles and legs were sampled in, but we need to make a final determination of which way we’re going on that.
Our plan is to bring these to AXPONA and what we show there should be cosmetically correct, as we have some time to rework / replace these sorts of things.
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Thank you, Chris. Neat history.
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Chris, thanks very much for that.
I referred Piega simply because of it’s unique coaxial ribbon driver. Piega is Italian for “fold”, the driver is the basis of the company’s product. The tweeter is not ‘clamped’ in the middle, the mid/tweeter is made as a single unit. See the links below. It makes it very expensive, as do CNC aluminium cabinets with internal metal bracing.
For example, their conventional aluminium bookshelf speaker with a ribbon tweeter and mid/bass driver is €1,600, so comparable to many quality mini-monitors, but their similarly sized aluminium bookshelf with the coax mid/tweeter ribbon and bass cone costs €7,000. So the driver carries a massive premium.
Their full range unit (down to 22Hz, 92dB sensitivity) costs €20,000, about the same as AN3. Their 4-part Master Line Source costs €200,000.
The Piega crossover is around 400Hz. Much higher than that would probably be problematic.
https://positive-feedback.com/Issue13/piegaloudspeakers.htm
With regard to your design, what struck me was the impact of the distance between the mid and treble ribbons, rather than the grilles, because I do understand that the effect of combing is frequency-dependent. As you say, the proof of the pudding will be in the eating - and the measuring !!!
p.s. I must admit that I’ve not heard of the USA brands you refer to. Lots of speaker brands do not travel well. Wilson from the USA, that are very expensive, are very popular in the UK. So are Martin Logan and Magnepan. However, Kharma, some of the best speakers in the world, have no distribution in the UK but are made only 250 miles from London. A dealer near me tried selling Piega Coax speakers, but they did not catch on and he gave up with them after a couple of years.
I owned Speakerlab 3s as a teenager in the '70s… built the kit… I loved those things.
Peace
Bruce in Philly
I built a set of speakers in the late '70s. I remember picking drivers from Speakerlab. Great memories!
I find this immensely interesting. Thanks for the knowledge!
So now I need to start looking for a pair of Genesis speakers on FleaBay??
No no No. But I just bought yet another pair.
Mmhmm. Saying no to hoard them all for yourself. I CAN HAZ ALL THE SPEEKERZ!!
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Hi Steven, I listened to a pair of Piega floor standing “full range” speakers with those coax ribbons last week in Switzerland, where they are actually made. CHF 11000 for the pair, driven by the T+A PA 2000 R integrated amplifier. In comparison to similar priced Burmester speakers driven by a a Marantz top of the line amplifier.
The treble of the Piega’s was impeccable clean calm and perfectly matching the midrange. In the treble it sounded cleaner than the Burmester. But: The Piega had no bass! From an overall impression, musical wise, dynamics, bass, livelihood of the music, soundstage, the Burmester with AMT tweeter and side firing woofer in an MDF cabinet took the clinical sounding PIEGA’s to the cleaners.
A difference day and night and I will not be looking for Piega anymore. It may also have been the combination with the T+A but that Amp with other speakers can do much and much better I have heard it more often.
The best I have heard are Rowen (to stay in Switzerland) or Avantgarde Acoustic horn speakers from Germany.
The Piegas made me feel comfortabel though, in the way that my current system, Canton Vento’s om my Yamaha AV receiver gives me more fun.
Also my experience. I theoretically nice speaker that sounds ribbon like fine and fast from mids up, but no energy, weight, color, emotion.
The sum is less than the single parts in this case. I guess a speaker’s soul is defined by the time given for crossover and voicing by people who really listen for music and not only use it as measuring/evaluation tracks and put together a technical piece of best practices and parts.
But probably this is idealized BS.
We agree with your advice about the matte finish. The actual units showed up last night (the picture I sent was a snapshot from the factory and not very flattering). Wow. In person makes all the difference in the world. The whole company was up and high fives
were every where. They’re gorgeous.
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More pictures, please…
Keep up the great work.
Yes sir, they will be in our room and the featured product. As I said earlier, one channel showed up last night and we assembled it. Wow. It’s just amazing in person.
Chris is one of the most knowledgeable, interesting, and genuinely nice people I have ever met in my 50 years in this industry. He can talk your ear off about any subject concerning speakers and drivers. He’s really quite amazing.
Chris will be attending Axpona with us to show of his new babies and if you’re interested in speakers and their designs I would encourage you to come by and let him bend your ear.
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The Genesis speakers were not accepted well for their aesthetics but from a sound quality perspective they were unmatched for their time.
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As your book noted. Yep. I’d get a pair if I found one. After all, as I note far too much, I have LS50s, which are FAR from traditional looking with that Uni-Q in bronze.