Yeah, ran through my screens and models again. 8P300Fe/N looks like my sweetheart for this mid dance. I realized that I'd never find the ideal driver and I had to give up something, so I gave up some sensitivity for lowish Fs, good xmax, low distortion, and very good Qms. I want to explore the reported greater musical detail at lowish SPL levels with a high Qms driver, and I'd like to be able to use the selected mid as a mid-woofer in a smallish TM down the road. I realize that Beyma shows 2.83v results, and love that you and others test real world performance. Glad you are finding goodness in the old JBL drivers. Tough to source a pair... Man I wish Beyma had shown the 8LW30 distortion in color! I can't separate H2 and H3 at a couple of spots.
But Chahly - Stahkist don't want speakers that look good, Stahkist wants speakers that sound good!
Updated data, as per request of a DIY member who sent a pair of old school JBL 2012HPL 10" mids. Conditions were identical to the other set of measurements I had made, even if they were a bit flawed. The reason for this was for the sake of consistency so I could graph the data together with the rest with all of them on the same level playing field. As with the rest of the speakers, these are a bit "cleaner than the numbers indicate". No I will not re-test.
Frequency Response 2.83V @ 1m, both speakers. Pretty consistent across the board.
Harmonic Distortion dB chart(s). All of these HD charts are with a sharp filter @ 4k to prevent the bump in the upper-midrange from overdriving the Omnimic prematurely so I could get the same SPL level out of the speaker @ 500Hz like I did with the other ones.
Unit #1
Unit #2
Yes, I can already see it. 3rd order HD is stupid low.
It's funny that a vintage driver like the JBL can hang with the latest FEA engineered drivers. Gotta be some really sharp guys who designed the original.
But Chahly - Stahkist don't want speakers that look good, Stahkist wants speakers that sound good!
Yup, it fared very well! It was very over-engineered/ahead-of-it's-time that's for sure. Has a full copper pole cap and who knows how much aluminum within the motor, and you can tell from the measurements. It's too bad you can't find them anymore, and the newest 10" midbasses from JBL are only in 16Ω from what I've seen. I guess they wouldn't be horrible for a MTM setup to have an 8Ω final impedance. Who wants to send me a pair of JBL 2251JPL's to test?
Representing American engineering amidst a horde of Italian and Spanish heavyweights!
Beyma just announced what looks to be a ferrite version of the 10MC700Nd, the 10MCB700. On the website, but not in production yet. Might have to snag a pair just to see what is what! Doubt it's better than the 10MC700Nd, but you never know!
As always, an interesting exploration (as long as it's not MY money!) - I'd say the MC7 is better - neo slu and a demod ring, vs the MCB7 with "only" a ferrite motor and demod ring. I'll bet the MC7 has less distortion. But then you run very thorough tests to verify claims. Actually surprised that you don't have your own Klippel rig by this time <grin>
But Chahly - Stahkist don't want speakers that look good, Stahkist wants speakers that sound good!
Comments
I realize that Beyma shows 2.83v results, and love that you and others test real world performance.
Glad you are finding goodness in the old JBL drivers. Tough to source a pair...
Man I wish Beyma had shown the 8LW30 distortion in color! I can't separate H2 and H3 at a couple of spots.
Frequency Response 2.83V @ 1m, both speakers. Pretty consistent across the board.
Harmonic Distortion dB chart(s). All of these HD charts are with a sharp filter @ 4k to prevent the bump in the upper-midrange from overdriving the Omnimic prematurely so I could get the same SPL level out of the speaker @ 500Hz like I did with the other ones.
Unit #1
Unit #2
Yes, I can already see it. 3rd order HD is stupid low.
Harmonic Distortion Percentage Charts
Comparisons with my 10's.
Representing American engineering amidst a horde of Italian and Spanish heavyweights!
https://www.beyma.com/en/products/c/low-mid-frequency/110MCB708/altavoz-10mcb700-8-oh/