I'm in the process of trying to improve the sound quality of a set of Kenwood KL-777D speakers that I saved from a trip to the dump. They were given to my wife sometime in the mid to late '70's - so they are orginal. All of the drivers appear to be in great shape; no dents, holes, or tears.
So far I have replaced the input terminals with new terminal posts. My next task will be to replace the capacitors with new ones.
Are there any other things I could do cheaply, to improve the sound quality as well? Would adding any insulation help? I've noticed many of the latest speaker designs have batting material inside. There is nothing like that in mine, just some 1/2" to 1" thick fiber carpet padding in the bottom half of the enclosure.
I know these speakers were never considered to be anywhere near "audiophile" class, and I don't expect them to now, they will be fine for my photo studio (garage)for now.
Thanks, Len.
So far I have replaced the input terminals with new terminal posts. My next task will be to replace the capacitors with new ones.
Are there any other things I could do cheaply, to improve the sound quality as well? Would adding any insulation help? I've noticed many of the latest speaker designs have batting material inside. There is nothing like that in mine, just some 1/2" to 1" thick fiber carpet padding in the bottom half of the enclosure.
I know these speakers were never considered to be anywhere near "audiophile" class, and I don't expect them to now, they will be fine for my photo studio (garage)for now.
Thanks, Len.
Not audiophile ?! What ???? They are my speakers !
First: remove the back panel . Remove the crossover . If you aren't going to use two stereo amplifiers , put a large (3-4 uH)inductor before the woofer . Putting Jantzen caps instead of the originals didn't change much .
But the best result is by using the big woofer in OB with a 10 dB bump below 100 Hz and cross it electronically at 500 Hz . Of course the cabinets should be kept horizontally to keep the mids aligned , but at this point also a big tweeter with a waveguide should be added to match the PERFECT quality of these drivers...
Bye
First: remove the back panel . Remove the crossover . If you aren't going to use two stereo amplifiers , put a large (3-4 uH)inductor before the woofer . Putting Jantzen caps instead of the originals didn't change much .
But the best result is by using the big woofer in OB with a 10 dB bump below 100 Hz and cross it electronically at 500 Hz . Of course the cabinets should be kept horizontally to keep the mids aligned , but at this point also a big tweeter with a waveguide should be added to match the PERFECT quality of these drivers...
Bye
Planet10 - I hope I can get this to work...
Picowallspeaker - No offense, but almost every post I've seen on these speakers they have talked down about them. The few good comments were about them only being good to play old rock at high volume, and I have to say, the way mine sound now is about like a loud clock-radio.
It almost sounds as if you replaced all the drivers and started over...
Any info will be appreciated, thanks.
Len
Picowallspeaker - No offense, but almost every post I've seen on these speakers they have talked down about them. The few good comments were about them only being good to play old rock at high volume, and I have to say, the way mine sound now is about like a loud clock-radio.
It almost sounds as if you replaced all the drivers and started over...
Any info will be appreciated, thanks.
Len
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picowall's suggestion is fairly radical, but often done. Many of these boxes had great drivers implemented poorly. My suggestion for a radical change would be to make them a 3-way by eliminating the 2 paper mid-tweeters and the horn, and redong the XO...
Leaving things as are, the box needs at least the walls lines, i'd be tempted to stuff the entire box with 0.25-0.5 pounds of polyfluff per ft^3 of box volume. Better wire, ductseal on the baskets, at least minimal bracing of the cabinet..
More invasive, would be to coat all the paper cones with mod-podge (thinned -- as little as you can on the mid-tweeters & midrange), more on the woofer (and both sides). The next step after that is to EnABL everything.
You could also take a router with a round over bit to the edges of the box (means losing the grills)
dave
Leaving things as are, the box needs at least the walls lines, i'd be tempted to stuff the entire box with 0.25-0.5 pounds of polyfluff per ft^3 of box volume. Better wire, ductseal on the baskets, at least minimal bracing of the cabinet..
More invasive, would be to coat all the paper cones with mod-podge (thinned -- as little as you can on the mid-tweeters & midrange), more on the woofer (and both sides). The next step after that is to EnABL everything.
You could also take a router with a round over bit to the edges of the box (means losing the grills)
dave
Dave's right ...
Mines are a little bit different , having brown paper cones , 2 big midranges ,2 little horn tweeters ,and the little mica one ,and being originally sealed boxes .
My advice is to remove the back panel (and throw it away) ,put some varnish stripper behind the bolts ,then remove all the speakers , put a big Hi-vi RTS2 tweeter in place of the little drivers ,try to calculate a good crossover design ,then using as a source a portable CD player having a digital (analogue is worse) bass boost.
Except putting a new tweeter ,that's what i did . The shape of the box allows for an H-frame OB design . At the end ,bi-amping allowed me to have only a little CL filter for the tweeter . Ehi! Remove also the cloth behind the grill
Bye
Mines are a little bit different , having brown paper cones , 2 big midranges ,2 little horn tweeters ,and the little mica one ,and being originally sealed boxes .
My advice is to remove the back panel (and throw it away) ,put some varnish stripper behind the bolts ,then remove all the speakers , put a big Hi-vi RTS2 tweeter in place of the little drivers ,try to calculate a good crossover design ,then using as a source a portable CD player having a digital (analogue is worse) bass boost.
Except putting a new tweeter ,that's what i did . The shape of the box allows for an H-frame OB design . At the end ,bi-amping allowed me to have only a little CL filter for the tweeter . Ehi! Remove also the cloth behind the grill
Bye
Thank you both for the replies. I ordered replacement caps last night and should have them by Friday. I guess that's my 1st step.
Planet10, I will probably seal the baskets and stuff with the fluff, not sure yet about sealing the driver cones though. With each of these modifications, what difference in the sound should I hear?
Planet10, I will probably seal the baskets and stuff with the fluff, not sure yet about sealing the driver cones though.
With each of these modifications, what difference in the sound should I hear?
The fluff should lower the Q of the box, refining the bass, and making it less lumpy.
Wire should improve the downward dynamic range... single strands of solid core CAT5 should work well for all but the woofer,
Puzzlecoating the cones will reduce the cone self-noise (ie increase downward dynamic range)...
dave
Wire should improve the downward dynamic range... single strands of solid core CAT5 should work well for all but the woofer,
Puzzlecoating the cones will reduce the cone self-noise (ie increase downward dynamic range)...
dave
Audiophile grade means that the speakers on the cabinet are at least vertically aligned to give a flat image on axis , and that can't be achieved nor changing the caps or wires nor alter the Q of the box or speaker's Q by putting felt behind the spider . Is following my way too difficult ? I just say remove and listen , not add endlessly something . At least , a good modern tweeter with waveguide is usable in other designs or betterments of existing speakers ,like this one . Also new capacitors ,of course ,those can be useful in future projects /rebuildings (if you keep the legs long !).
The only drawback of going Open Baffle is that you need a lot of space around the cabinets.
Bye
The only drawback of going Open Baffle is that you need a lot of space around the cabinets.
Bye
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Woofer, midrange, 2x upper midrange?, metal tweeter and a horn! Wow.
Not much science in their design I suspect. Made to visually impress in their day. (How many drivers can we stuff into this box?). A relative of mine had a pair of Kenwoods some years back. Not the same as yours but still had numerous drivers in an odd layout. Lots of ting and boom but very unrefined. You might be flogging a dead horse but good luck anyhow.
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