By "coil assembly," are you asking the dimensions of the voice coil, or the field coil magnet structure (like ~4" D x ~8 1/2"L?
Hi Serenechaos,
Yes, I mean field coil magnet structure; diameter x length.
Cheers,
Peter.
Just a thought, if the field coil magnet assembly is 4"x8.5" then its going to restrict its use to almost only in OB as the back of the magnet at that length will surely need to be supported. Shorter design would be more enclosure friendly IMO. Don't mean to be picky
Center is drilled/tapped 1/2-13 for support bracket/bolt/mount.
Smaller diameter allows free movement of sound wave from rear of cone, lowers reflection back into cone, distortion.
Works very well w/ FLH; much better than OB IMHO...
Tubes & Horns-- a whole new level!
OK, dims are correct. Reason for that size is also correct. Use in a typical BLH will require some design changes, but various Tannoy and Lowther designs from the past show that this is not a major problem.
Horns vs Open Baffle. I find they can both be excellent, and I prefer OB's for some types of music, horns for others. YMMV.
Would love to provide a better support system than a threaded bolt hole, but we are having a hard time finding something that is sonically transparent and universal to the various designs.
Jon,
How much does the motor system weigh, and is there an absolute need for a support other than from the front baffle?
Also, will you be doing a version of this with a silver voice coil. In your opinion does this make much difference?
Thanks
David
I do not have an exact weight, but would guess it to be in the 25 lb. range. Without a secondary support their is a high probability that the voice coil would begin rubbing. A metal support will probably be supplied to make mounting easy.
The standard voice coil is aluminum. This was picked due to its low weight, helping with transient response. In comparison silver sounds cleaner, copper sounds warmer. The silver does not appear to affect highs greatly when compared to aluminum, my guess is that the "silver sound" offsets the additional weight. The copper does decrease highs, but if you have a high flux density the highs tend to be accentuated, and the copper coil balances this.
These are minor flavorings, but important in a refined system. The current field coils are using copper voice coils, and were meant for an open baffle. Further testing in a front loaded horn is required in order to make a proper recommendation. Cones will be made available in 8 or 15 ohm, and with all three voice coils metals.
The copper field coil does affect highs, quite noticeably.
Jon,
what "types of music do you prefer OB's for," over FLHs?
I thought the tubes/FLH/copper field coils were noticeably better than the ss amps/OBs, and better than any cone driver I'd heard, for any style.
Cleaner, clearer, more detail, less sound bouncing around the room, comb filtering, cancelling etc.
Just curious...
Jon,
what "types of music do you prefer OB's for," over FLHs?
I thought the tubes/FLH/copper field coils were noticeably better than the ss amps/OBs, and better than any cone driver I'd heard, for any style.
Cleaner, clearer, more detail, less sound bouncing around the room, comb filtering, cancelling etc.
Just curious...
The big azura's played big and bold better than anything I have heard. Just wonderful on orchestral, and pieces with big dynamics. Although the sound of female vocalist was spot on, they sounded huge, and the imaging was off. Ella sounded great, but larger than Shaquile. I preferred the OB's presentation in that regard. This could be an artifact of the rooms rather than the systems. The Azura's were in a much larger room, and the OB's in a smaller room.
I do have to agree with your assessment overall. That was a special, highly refined system that showed years of work by the owner. It is rare that you get to hear such a system which is so well put together. I could have happily lived with it.
cheaper choice than PM4A?
Just finished the bass horn part, will add front part in future. Any driver recommendation other than PM4A for Azurahorn? I am using DX3 now.
Following from Martin Seddon,
"No back chamber - I actually think one wants the maximum upward extension from the back horn - you can try sheepskin on the floor of the bass horn if you feel too many highs come this way. I am using Lowther PM2A on the bass horn alone up to 800Hz with 6dB roll off above. I have found the mid range sounds just great down the long horn."
Just finished the bass horn part, will add front part in future. Any driver recommendation other than PM4A for Azurahorn? I am using DX3 now.
Following from Martin Seddon,
"No back chamber - I actually think one wants the maximum upward extension from the back horn - you can try sheepskin on the floor of the bass horn if you feel too many highs come this way. I am using Lowther PM2A on the bass horn alone up to 800Hz with 6dB roll off above. I have found the mid range sounds just great down the long horn."
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What flavor do you want? The DX4's do fast & dynamic really well, the PM series does more warmth and harmonic development. As the magnets get larger you get more information and better dynamics, so the PM4A is the king, and below them are (in order) the PM5A, PM2A, PM7A, PM6A. All will work, and be thoroughly enjoyable. The Field Coil is truly outstanding, but pricey.