Hi Romy!
The 515-8GPH were in same scale as the 515G with slightly above 35Hz resonance frequency and 103 sensitivity - a very good candidate for 60Hz horn. The 10” throat? No bolls to go for 9”, how about 8”?
Got the balls, but not the room;-) with the lenght of about 51", backchamber included, the mouth will be quite close to the place where my living voice airpartner -clone (pic on peter empsons site) sounds best.. this folded horn(open bachchamber...somewhat boomy bass) works in same frequency range, so i thougt it will be a good place to start with the straight fronthorn.and a listening distance of 11ft is not really much...
The S2’s diaphragm with clear plastic outer suspension is an original Vitavox cone that they did as a substitute for metal suspension in order to add a slightly more power handling for the S2 driver. i searched your site and the web, but could not find a pic with the same diaphragma.
it seems to be completely alu, but with a clear plastic-ring glued over the border of the hemisphere and the flat part with the grooves.its not the same like the white suspension, its just a 0,2 inches wide ring of clear something, the suspension itself seems to be alu. bought it new in 1994 as far i remember.(hard for me to find the right words, i apologize for my bad english..). red part in the pic alu, black clear plastic.
The Alnico vs. Ferrite on 515 driver? If you cross it at 500Hz and most likely with second order then I would say that there is no differences. Alnico is important to provide transients at mid and higher frequencies it would be less affective, if any at bass. Not to mention that it would make the bass channel more vulnerable to DC component demagnetizing. Alnico is better reacts to low level signal but it might be negligible in your case. If you do have a luxury to choose type of magnet in your 515 then I would go with a magnet that would depend from your amp. The basic rule is that I formulate for myself is following: SS PP amps must not driver Alnico and SETs must not driver ceramic frequency above 500Hz-1000Hz. If you use SS PP amp then a ceramic magnet is a must as Alnico would too much highlight imperfections of PP topology. With 500Hz crossover it become not so critical. have a we91-style 300b, ouput amouphous core frome tribute, very detailed and sweet at the same time. hard to deside, my budget is limited, but i dont want to make to much compromisses...
thx, klaus
Rgs, Romy the Cat |