Scanspeak? I always worry about the longevity of paper drivers. I've seen them literally disintegrate in vintage speakers
Sure. I trust you are familiar with HiFiCompass and their driver testing. Bliesmas come out as outstanding performers, like Purifi and some others. Measurements only don't tell the full story, hence I went for a listen. This is still not the full story as you still have to implement them, but it’s as far as I can go without spending the money.
Believe me, some significant soul searching going on before I cough out that much dough!
Oddly enough the Electro Voice 15W with a paper cone lived in South Louisiana for 40 years before moving to Denver Colorado. Original cone and surround about to play once it is beer time.
Where did you happen apon this chance? Someone nearby with a set already implemented?
I emailed Bliesma to ask some questions. Eventually asked if there would be DIYers that wouldn't mind me getting in touch. They noticed I was from Argentina and came back with a name that happened to be in my city - kind of odd! - and I went for a visit and heard what he assembled. A top-notch system. Serendipity happens!!
Wow. Very impressive. So, so expensive. Though perhaps worth it.
Interesting @LewinskiH01 , I went with the M74Ts, but the M142s (A or T not B! 🙂) again drifted into my thoughts this morning and I had a twinge of regret for not ponying up for them. I suppose it comes down to where we want the crossover. ~250Hz and 1.3-1.5K with the M142 and T34 v 500 and a bit higher with the M74.
My current research is trying to find a solution for 500hz and down.
Bill
I think one problem that quite often occurs with very old paper cone drivers is related to a moisture/climate situation
where the moisture actually leads to the corrosion of the 'flexible wires' that connect between the terminals and voice coil 🙁
One 'handy hint' I give to people using old woofers, is to gently coat these flexible wires with engine oil. [ not a thin WD40 spray ]
I heard the M74B and liked them very much. Didn't hear the A or T, but HiFiCompass provides comparisons in terms of measurements and his listening. Not sure if the difference from T to B is worth the extra money, but then again I didn't hear both.
The owner of the system I heard mentioned BluesMa was planning a M142B but issue in the B supply chain lead to canceling that plan. It would be a lot more expensive too - much more than the M142T! What I heard was the M142P. The owner is moving into M142T, which is the same one I'm thinking through.
I asked Bliesma and they aren't planning an intermediate sized dome between M74 and M142. So it's down to required xo and SPL needs. HiFiCompass shows 500Hz is lowest xo suitable for M74, and preferably 600Hz. M142 down to 250Hz.
My midbass is a SLOB with 8x 6.5" per side like xrk971' XSD but with different drivers. It goes naturally to 470Hz where it drops. I could push them to 550Hz, maybe 600Hz, but I need to test how they would sound. The M142 starting at 250Hz sounded very good but I don't really need to xo that low. But M74 needs a xo that might be too high for me.
FWIW, xrk971 SLOB work amazingly well. You could look into a similar setup with smaller drivers and achieve 550Hz xo. I just happen to have built with 6.5" already. Even with 6.5" it does get easily to 470Hz and probably to 500Hz too.
You are dead on right: I checked their prices and the M74B is more expensive than the M142T, at €1200 vs. 1100 approx! Beryllium has gotten very expensive!!