Substitute for Speakerlab S3 Midrange Driver

[Bratwurst7s]

Yes James, they are old. I should just change them now so I only have to unseal one speaker. My motorcycle project is nearing its end so, it's time.

Nerdorama, my Adcom GFP1 pre-amp has tone controls so I can roll off some bass. In fact, that's how I used to run it with the GFA1 power amp. I always felt the bass response on the S3 was strong. And just guessing, judging by the pictures of the original Speakerlab crew, I'd have to say their speakers were designed with the Greatful Dead in mind. LOL. Trying to replicate the Wall Of Sound.
https://m.facebook.com/hifi/videos/...technology-of-live-music-the/218617439591159/

Just making a few guesses here, but...

Your perception of the amount of bass you are getting at this time may in part be a result of diminished mids over time because of the state of the caps in that circuit, and the need to turn up the volume to reach the output that makes the mids wake up. When you replace the old mid caps you may at first have the impression that there is less bass, but in reality that will be the result of the speakers being more in balance again and with the mids having more output you will be using less overall volume to reach the point where the mids and highs sound good, thus effectively less power to the woofers at that overall loudness point.

Once you get to that point the speakers will be sounding overall much better and you will be at the point where you might get the itch to explore film caps and/or film bypass caps in the tweeter and mid section. The more that you go in that direction the more balanced the bass will sound.

Cheers,
James

 

[nerdorama]

Here's a nice explanation of the Linkwitz Transform. It is more than a tone control. An ordinary tone circuit doesn't alter the Q of the system.
https://sound-au.com/linkwitz-transform.htm

 

[blipco]

Yes, the perception. It's hard to compare with a sample size of one, plus time, plus faded memory. My best recollection was that the S3 had a flat response. No color. I don't recall them being so bright.
I realize that no amount of talking will make my capacitors young again but on vocals, these mids are really popping. I will have to turn down the pads to soften them.. something I never had to do before.

 

[blipco]

Here is my small update thanks to the great and much needed help I have received here.
I have ordered the new caps. I just don't want to button up my speakers leaving 40 year old capacitors in there. I even ordered two 4uf caps to replace my paralleled 2.2. So I will go back to the way it was designed.
I had to order four 12uf caps to equal 24uf per crossover.

I'm glad I'm doing this but I think I'm doing something totally non-purist also. I have ordered the Schiit Audio Loki+ equalizer. It gets good reviews from audiophiles (and it is cheap enough if I don't like it).
My other thought is that if I like the tone control I get from it I can maybe somehow modify my ancient Adcom preamp and cut the tone and filter section out of its circuit for a more direct path for the signal. (But that is only an inkling of a thought as of this moment).