Good to hear from you lowmass
Diva - distance is .170” (magnet face to foil ) or 4.318 mm
Scintilla - distance is slightly more around 190”
Duetta signature uses the same magnet height as diva (.440”) so should be the same
distance away although never measured
Magnepan not sure , but they use a weak magnet system for bass ( brown strip magnets ?) that for every cycle 4 extra cycles get thrown in for free
I think they wanted a loose bass signature
Actual excursion is amplitude dependent as you know but a subjective impression is maybe 3mm at a level
I consider high
Regards
David
Diva - distance is .170” (magnet face to foil ) or 4.318 mm
Scintilla - distance is slightly more around 190”
Duetta signature uses the same magnet height as diva (.440”) so should be the same
distance away although never measured
Magnepan not sure , but they use a weak magnet system for bass ( brown strip magnets ?) that for every cycle 4 extra cycles get thrown in for free
I think they wanted a loose bass signature
Actual excursion is amplitude dependent as you know but a subjective impression is maybe 3mm at a level
I consider high
Regards
David
Thanks all
Yes helloo David! been a while eh?
Thanks for the info
yea the Magnepans extra cycles are the undriven sections of diaphragm between the wires continuing the dance after the band went home
I supose the newer foil traced version should be a bit better as the foil covers a wider space than the wires
Yes helloo David! been a while eh?
Thanks for the info
yea the Magnepans extra cycles are the undriven sections of diaphragm between the wires continuing the dance after the band went home
I supose the newer foil traced version should be a bit better as the foil covers a wider space than the wires
Theres a Youtube video by OCD Hifi Guy where he states that the diaphragm to magnet distance on his maggies
is 1.6 mm.This wouldn`t surprise me given the weak rubberised "fridge" magnets that Magnepan use.
I recently replaced bass ribbons on my Apogee Duetta Sigs and measured the ribbon to magnet distance as
4.5 mm.
is 1.6 mm.This wouldn`t surprise me given the weak rubberised "fridge" magnets that Magnepan use.
I recently replaced bass ribbons on my Apogee Duetta Sigs and measured the ribbon to magnet distance as
4.5 mm.
for most maggies its around 1 to 1.5 mm i believe, witch might not be a problem since they go usually for more surface area. its all about moving air. but then again this is the reason why people often say the apogee has more slam... since they might be half the size in surface area... but has 4 times the excursion. and lower res... half the res means 4 times the excursion at that frequency. its a trade off. go low. or go small xmax and bigger surface area and slightly higher res. etc
The difference in bass dynamics between Magnepans and Apogees is very obvious, having owned both. Increasing volume with Magnepans is almost like having a limiter kick in the woofer section. If one looks at the surface are of eg. Duetta and MG 1.5-1.7 which are roughly the same size category the Duetta has according to specification 3750 cm2 vs 2850 cm2. Going up to the 2.7 model gives 4000 cm2.
Its not clear what Xmax the Diptique has, they do user bigger magnets not sure what type., i never tried there cross coil design, besides that i believe they patented it. with ferites single ended 3-4 mm xmax is doable. and price not to insane. in push pull this might be more around 6mm one way. but it does get expensive. i buy mine around 60-75 cents a piece if you buy allot in one order and are 100mm long. but it adds up rather fast. 100mm long neos are around 1 euro a piece. if you buy allot. (1200 or so) now problem remains that the neos are less wide so more of them are used but the output is muuuch higher of course. if you would make this push pull (must find a better name for it since it is not push and pull, but everyone calls it pp) witch should be push push 
it becomes really expensive and the need for a really sturdy frame and a hell of a assembly that makes it really scary.. you might **** up a few hundred euros in magnets, steel , membrane and time in less then a second
it becomes really expensive and the need for a really sturdy frame and a hell of a assembly that makes it really scary.. you might **** up a few hundred euros in magnets, steel , membrane and time in less then a second
i agree, i never heard the apogees, but made a few panels with large ferites, and they do have a different sound.. and i lkike them better even when the total surface area is less then a small maggie.
I think, the Diptyque PPBM patent can be two "single ended" system in opposite application. The magnetic field isn't superposed regularly (lowered the efficiency), but the undriven area of membrane is divided smaller quadratic areas. I think, there is ferrite blocks, the induction is around 100mT at membrane traces, but the driving force is symmetrical (and pretty linear) to rest point. The rated 86 dB sensitivity can be an evidence (relative low for PP magnet assembly).
in any case both magnets will short to each other where they meet alternating and every other vertical magnet it pushes against it like a normal PP. since vertical is north south north, and horizontal is to. some do push against each other some dont. and will short out to the opposing magnet. (if that is put to use its not all lost but i was always worried about coils going horizontal and vertically been in a field not corresponding to what it should be at some points... then again i never tested it so wo knows. might be one of those things that looks like a bad idea but might work..... femm is not capable of modelling that so cant confirm
but i was always worried about coils going horizontal and vertically been in a field not corresponding to what it should be at some points... then again i never tested it so wo knows. might be one of those things that looks like a bad idea but might work..... femm is not capable of modelling that so cant confirm
yeah they look like rubber magnets, maybe Ndfeb ones ? else they will not reach much of Xmax max 1-2mm if the drawing is anywhere the real thing
since ferite ones are weak. and Ndfeb are... well expensive
hmm nice i never seen the left picture. it indeed shows it is rubber. and slightly wider then we are used to maybe slightly thicker to (5mm give or take). but not really all that impressive. weird
almost looks like STRIP ANISOTROPIC 9X6 MM rubber magnet or the 12 mm version
since ferite ones are weak. and Ndfeb are... well expensive
hmm nice i never seen the left picture. it indeed shows it is rubber. and slightly wider then we are used to maybe slightly thicker to (5mm give or take). but not really all that impressive. weird
almost looks like STRIP ANISOTROPIC 9X6 MM rubber magnet
or the 12 mm version
Last edited:
Many thanks for good pictures!
My suspicious think: the U-shaped magnetizing of strips not generate too much repellent force, if they take to opponent position, but not pole to pole (N-N and S-S at true PP arrangement), but crossed direction. This is the secret of PPBM! No more need a lot of steel support and crossbar, the cheap laser perforated metal sheet is enough. The price of this idea is the smaller membrane excursion and lower efficiency.
My suspicious think: the U-shaped magnetizing of strips not generate too much repellent force, if they take to opponent position, but not pole to pole (N-N and S-S at true PP arrangement), but crossed direction. This is the secret of PPBM! No more need a lot of steel support and crossbar, the cheap laser perforated metal sheet is enough. The price of this idea is the smaller membrane excursion and lower efficiency.