More experiments.....
Been listening to the stock JBL 5325 crossover today with 4345 cards that just arrived from Santa Rosa CA....thankyou SpeakerDave.
Well its been very interesting.
The good news is it's very clean sounding.
The bad news is the 5235 crossover makes every recording sound the same .......
.
A . By this I am referring to the presentation......there is a very strong sense of presence in the midrange, lots of drive.
If your JBLs sound in your face then this is why.....and ultimately fatiguing.
I think this is another long held characterisation and a false one at that of JBL's in particular the 4343 that is going to be sorted out in this project.
Basically the speakers are a hi end system and it these sort of issues that ear mark hifi from hi end.
B. I compared it to my own crossover and it by comparison sounds perhaps reserved, not in your face. Once I played different stuff the skill of the recording engineer becomes obvious. The music has soul and natural energy.
Removing the active crossover gives the same result as B with some loss of bass detail.
I will attempt the null dc offsets the discrete opamps and bypass the coupling capacitors (B) and see what happens.
I decided to completely
bypass (short out) the audio coupling capacitors in a key area just to see what might happen.......
Well let me say its going to stay that way......
I will refer to this as the
Earl revision to the design.
The very fine detail and nuance at frequency extremes has opened up while the mids now a sheer clarity that is difficult to describe. Individual tracks appear to take longer to play while at the same time I now feel compelled to focus on the characteristics of specific instruments.
This perhaps is a sign of one being at ease and accepting the sound as correct.... I think so.
I now propose to charge couple the polystyrene capacitors in the actual crossover filters. This will be referred to as the
Giskard revision to the design.
What amazes me is that one easily can pick and hear all these refinements up on a 20+ year old loudspeaker design.
Ian