after several hours drive at 6mm or so p-p, fs only dropped by 0.7Hz, 30 minutes after removing the drive, qes was still up a bit so small signal qts sit at that point around 0.74. I doubt if fs will go lower .
grabbing a Nirvana Super 8 (stamped frame) Fs ~59.22Hz and qts ~0.32. Something in Nirvana's suspension works over time to raise fs by around a half octave. My super 8 started fs ~42Hz. My super 10 started fs around 48Hz. (much above spec)
In the budget 8 inch range, BG20 is one consideration. MCM's BOFU would save some money and Newark sometimes has coupons for additional savings.
grabbing a Nirvana Super 8 (stamped frame) Fs ~59.22Hz and qts ~0.32. Something in Nirvana's suspension works over time to raise fs by around a half octave. My super 8 started fs ~42Hz. My super 10 started fs around 48Hz. (much above spec)
In the budget 8 inch range, BG20 is one consideration. MCM's BOFU would save some money and Newark sometimes has coupons for additional savings.
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Freddi,
I wouldn't worry about them going soon, they have 173 in stock and more expected inventory coming in around 11/5/18. FYI they also have a 3.5, 4.5, 5.25, and 6.5 inch ones in the series. The 4.5” looks like the grs 4.5”. I hope to try out some of these too.
I wouldn't worry about them going soon, they have 173 in stock and more expected inventory coming in around 11/5/18. FYI they also have a 3.5, 4.5, 5.25, and 6.5 inch ones in the series. The 4.5” looks like the grs 4.5”. I hope to try out some of these too.
I've come across a variety of 8 inch ceiling speakers at Newark too, this one from Quam Nichols (American made) http://www.newark.com/quam-nichols/...hm-20/dp/98Y0229?st=8 full range quam Nichols looks interesting, very limited specs though. Might be a good ob candidate. Back to topic now . . . .
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I put the GRS BOFU in a Karlson 12 - can feel drums and not much excursion to so (~1.8" p-p) but its tonal balance is too dark / murky. Some high q speakers with strong mids and treble play just fine including Fane's 12" FR, Semprini 12, University UCX-22. I don't know if a helper tweeter can get it better except on the highs. Maybe I'll put the GRS into an R-J 12 - or Eliptoflex.
I've probably built more speakers with Quam drivers than anything else as they were dirt cheap/free in the '60s and all were quite good and durable as many I did were for various outdoor, vehicle apps.
No specs, but in looking back performance wise they were all same as today's PA/ceiling speakers such as this EV re-badged Altec 409 8": http://av.loyola.com/products/audio/pdf/ev-409.pdf
GM
I'll have to pull the GRS and get my mic - preamp setup running again - it might be ok as a direct radiator. PRV's 10FR should run nice in a K12
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