Absolutely beautiful, but probably out of my price range and not suited to my multipurpose room.
Field Coils for Audio Systems
- Thread starter Audiophile Bill
- Start date
Best?
Do you want a compression driver for a horn, or a direct radiator?
I use and really like the Supravox 215 ( 8" ) which has a range from 50Hz to 6KHz (no whizzer cone).
I have heard and been really impressed by the Rullit Aero 10" which have a wider bandwidth 50Hz to 15KHz.
Voxative make a range of 5" Lowther style field coil drivers.
Wolf Von Langa makes a range of compression driver field coils including a 4" in the style of the JBL 375, which I am told sounds fantastic.
John Wolfe at Classic Audio also makes and sells this style of compression driver.
There are Ken Songa's speakers, but I don't believe that he sells the drivers.
I am sure that there are many more choices. I hope your pants don't catch fire
Good point - I'm looking for a radial driver, not a horn.
My first experience with field coil was wolf von Langa which led me to start building some. I wanted to buy their drivers but they stopped selling the drivers by themselves.
I'm going to check out those supravox.
Ive heard people with experience claim the vox are maybe not giving the bang for the buck.
Nobody mentioning ems/fertin. I've been interested in those, but I feel it may be a sideways move from my sonido.
I have $10k which isn't huge budget but for 2 drivers it isn't bad and I don't really need anything else these days and don't want to fritter it away on capacitors.
If you want a single driver approach, the Rullits could be your best bet. I heard them in an open baffle and they were beguiling. The only down side is that you won't have a lot of bass below 50Hz.
Rich of @Treehaus Audiolab uses them in his full range OB speakers and has a lot of experience with them.
That's a question likely to generate a lot of answers unrelated to each other.
The 'best' won't have any breakups in the range for which its intended. That pretty well rules out most paper cone midrange drivers.
The reason to consider a horn is twofold. First the horn has controlled directivity, which is useful for minimizing early reflections from side walls which the ear interprets as harshness. The second is the driver doesn't have to move as much and in simple terms that means its distortion can be lower.
I've been living with both models of Classic Audio Loudspeakers, the T3.4 and T1.5 Field Coils. They offer an incredible combination of dynamic range and detail, while also being smooth and transparent. I find them exceptionally musical and prefer them over the LM-3 Line Magnetic Field Coils, which are a clone of the Western Electric 22a Horn that i have had for over 3 years at the same time.
The Line Magnetic Horns tend to peak on certain dynamic tracks, resulting in a ringing noise. While the LM offers a large, room-filling sound, its soundstage is somewhat diffused. In contrast, the Classic Audio speakers are more refined and transparent, providing a more precise placement of instruments on the soundstage.
When comparing the horn on the LM3 to Classic Audio, I find that I prefer the Classic Audio for long-term listening. Both speakers are incredible, but for extended ownership, the Classic Audio Loudspeaker consistently wins me over. It handles delicate tones with refinement, delivers explosive dynamics, and allows music to effortlessly float in the air.
The Line Magnetic Horns tend to peak on certain dynamic tracks, resulting in a ringing noise. While the LM offers a large, room-filling sound, its soundstage is somewhat diffused. In contrast, the Classic Audio speakers are more refined and transparent, providing a more precise placement of instruments on the soundstage.
When comparing the horn on the LM3 to Classic Audio, I find that I prefer the Classic Audio for long-term listening. Both speakers are incredible, but for extended ownership, the Classic Audio Loudspeaker consistently wins me over. It handles delicate tones with refinement, delivers explosive dynamics, and allows music to effortlessly float in the air.
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Something I forgot to mention: The LM3 is a much more coloured speaker, offering a warm, glowing tone to voices that can seem saturated and slightly fuzzy. It lacks the inner details that the Classic Audio horn captures, such as the breathing, the movement of the singer's lips, and the finer nuances in pitch.
I second your opinion regarding the Classic Audio field coils. I am using the 4" field coil midrange and the 15" field coil woofers. Very fast, transparent sound. The LM aims to recreate the vintage WE sound, and so would be different. The Classic Audio aims to produce a modern loudspeaker using an old but still superior technology. Interestingly, I visited the Hong Kong distributor for LM. He has a vintage WE system using the 594 field coil midrange drivers on multicell horns, with genuine 597 tweeters and 18" drivers in vented cabs. This system has the most stunning midrange I have ever experienced, in terms of realism and tonal density. Sadly, the 594 is rare as hen's teeth.
Agreed with above, which is why in the Treehaus designs there is a woofer to augment the frequencies below 90-100hz. Their roll-off slope on their own is pretty gentle, depending on taste you might be able to get by without any bottom end supplement. That all said, they are some of the most "full range" full-range drivers made.
My fairly limited experience with horns hasn't been positive across the broad range of music I like (including punk, hip hop etc...). Some amazing elements but with the ones I auditioned closely (the...trios...from that company that makes the uno fino I can't remember) got pretty muddled and shouty and basically unlistenable with complicated, racous music (the decemberists).
If the Decemberist (great band and I love how they are unapologetic about their REM influences) are causing a sonic breakdown then there are some real issues. I personally do not like the sound of horns; although I wish I did because they make high efficiency a lot easier.
I actually use them as a bit of a torture test. When they get 10 instruments going it can put a lot of pressure on a system I find and the avante guard couldn't handle it at all. I also find his voice can sound very dry on a lot of systems.
Sounded so bad on this $100k system it was basically painful.
I'm curious what other field coil drivers you've played with other than the ruilet?
You're sort of my speaker spirit animal (same taste in aesthetic, sound and music) so I would love to hear your thoughts on drivers....
Ive tried Supravox, and a variety of other non-FC full range (including a few of the Coral clones). It is really hard for a full range driver to do it all and do it without getting beamy or edgy, or muddling itself up when doing a lot at once. I discovered the Rullit stuff early on and kind of fell in love with it; and having later compared it to other options, it sounded the most "right" to my ears. They do not measure super flat, but they sound quite natural and neutral in the right places to me. I really liked the approach Zu audio took with having a full range driver and augmenting it where necessary, and it was a starting point for developing my own products. I also like SET amplifiers, so keeping things as efficient and easy-to-drove is a lot easier with the Rullit drivers.
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The sound is very forward and mid focused, similar to what you typically find in most full-range, single-driver, or dual-concentric speakers.
Horns are quite variable in their sound, in the same way that class A amps (which includes solid state) can be variable. If the throat design is correct, if the taper of the horn is correct, if the diaphragm is free of breakups (which tend to be exacerbated by the horn) then they are as smooth and neutral as any other speaker.
Put another way, if you didn't like a particular horn (consistently with that model regardless of the venue/equipment used) then its the fault of that horn design rather than horns in general.
If you sit in front of the speakers and listen, you will definitely not say that anymore. The converted Telefunken field coil works excellently in the reso housing because they were designed for that. They are huge housings that are open at the back. In a narrow open baffle they work well from 80hz-14khz. Then you combine ATK cornerhorn that works perfectly 20 hz- 80hz with 100db/w.
Scroll down in the link you can see the cabinet
Glow in the Dark Audio - Atelier Rullit Aero 8 Alnico
Glow in the Dark Audio showcases Kevin Davis’ personal collection of small-scale, DIY and one of a kind hifi audio gear, with a focus on single ended and push pull tube amplifiers and full range open baffle speakers.
Looks very interesting! Has anyone measured the Telefunken drivers to see if there are any breakups?If you sit in front of the speakers and listen, you will definitely not say that anymore. The converted Telefunken field coil works excellently in the reso housing because they were designed for that. They are huge housings that are open at the back. In a narrow open baffle they work well from 80hz-14khz. Then you combine ATK cornerhorn that works perfectly 20 hz- 80hz with 100db/w.
Scroll down in the link you can see the cabinet
With 2 Cornerhorns and 10watt amp ,you wreckingball your home ...promiseGlow in the Dark Audio - Atelier Rullit Aero 8 Alnico
Glow in the Dark Audio showcases Kevin Davis’ personal collection of small-scale, DIY and one of a kind hifi audio gear, with a focus on single ended and push pull tube amplifiers and full range open baffle speakers.glowinthedarkaudio.com
Never seen mesurements from oleg rullit drivers sorry. For me to expensive he modified everything on that centering spider, cone etc.
There was a German website that measured Telefunken and Klangfilm fied coils , but unfortunately it no longer exists.
Here used for ~8k€
Diverse / Andere Rullit super Aero 10 Field Coil (8047138620) | Gebrauchtgerät | Chassis | Angebot auf audio-markt.de
Angeboten wird „Rullit super Aero 10 Field Coil“ von Diverse / Andere als Gebrauchtgerät aus der Kategorie „Chassis“ bei audio-markt.de - dem Online-Marktplatz für High-End. Das Inserat mit der Nummer 8047138620 endet am 22.10.2024 um 10:35 Uhr.
I'm waiting for J1.5 speakers Classic Audio
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