L-Bone
09-23-2017, 06:28 AM
hi everyone,
I have been collecting jbl stuffs for several years now and I have been running a pair of heavily modified c50 Olympus speakers for some time. over the past while I have been slowly tweaking the setup and have know gotten it to the point where I am pretty happy with it but am still not completely happy with the mid range on these.
A bit of background on them. I bought them from the original owners family who bought them new in 1969. the original owner tweaked them over the years including double layering the cabinets (very tastefully still maintained the original look), made custom ports that replaced the passive radiator with a much improved sound difference, added top mounted 2440's with 2397 horns and 2405's for uhf and custom crossovers designed and built in the U.S that I was told had cost over 3k.
From what i have read the titanium diapragms come from the 2445 and have extended highs with a roll of about 10 db at 10 k to about 20k where as the phenolics drop hard at about 9k. JBL states that the 2405 should be run over 7k and I am wondering if most crossover designers would roll it in at that point and if a 2k slope between the 2 drivers would be good? I really don't have any specs on the crossover and I guess the only thing I could do would be run a signal generator though my ipad to see where they roll off and in but am not really sure if I trust this method.
I am looking for input on phenolic vs aluminum vs titanium and opinions on if crossover reworking will be necessary to get a smoother, warmer more detailed mid range.
thanks!
I have been collecting jbl stuffs for several years now and I have been running a pair of heavily modified c50 Olympus speakers for some time. over the past while I have been slowly tweaking the setup and have know gotten it to the point where I am pretty happy with it but am still not completely happy with the mid range on these.
A bit of background on them. I bought them from the original owners family who bought them new in 1969. the original owner tweaked them over the years including double layering the cabinets (very tastefully still maintained the original look), made custom ports that replaced the passive radiator with a much improved sound difference, added top mounted 2440's with 2397 horns and 2405's for uhf and custom crossovers designed and built in the U.S that I was told had cost over 3k.
From what i have read the titanium diapragms come from the 2445 and have extended highs with a roll of about 10 db at 10 k to about 20k where as the phenolics drop hard at about 9k. JBL states that the 2405 should be run over 7k and I am wondering if most crossover designers would roll it in at that point and if a 2k slope between the 2 drivers would be good? I really don't have any specs on the crossover and I guess the only thing I could do would be run a signal generator though my ipad to see where they roll off and in but am not really sure if I trust this method.
I am looking for input on phenolic vs aluminum vs titanium and opinions on if crossover reworking will be necessary to get a smoother, warmer more detailed mid range.
thanks!