Upgrading vintage speaker internals?

0 Members and 1 Guest are viewing this topic. Read 396 times.

Hobbsmeerkat

  • Full Member
  • Posts: 644
Upgrading vintage speaker internals?
« on: 18 Feb 2020, 08:20 pm »
Hi all!
My dad has a pair of late 1970s ('78 iirc?) Technics SB LX5 3-way floor standers. Despite their age, they still sound pretty good, but i dont have too much experience with Hi-Fi, but Id say "rich" and "warm" are pretty good descriptors, esp when compared to my personal Samson Active studio monitors with a 5" Woofer and a folded ribbon tweeter. There are no issues with the cones, domes or the surrounds, thankfully, but its definitely not without its faults, cuz it looks like it was made with rather cheap particle board, with no infill or possibly even bracing.

But I was curious if it would be worth doing some internal upgrades?
For example, upgrading the crossover with the same but newer, better quality components/wiring, and installing some braces and NoRez, along with tube connectors instead of clamps, to keep the original looks, but increase their clarity & reduce its cabinet resonance?

Or is this just a case of "If it ain't broke, dont fix it"?
« Last Edit: 19 Feb 2020, 04:25 am by Hobbsmeerkat »

Hobbsmeerkat

  • Full Member
  • Posts: 644
Re: Upgrading vintage speaker internals?
« Reply #1 on: 20 Feb 2020, 04:48 am »
I took some pictures. And looked inside the speaker cabinet and its super barren. lol
Tho it might not be as old as i thought? Could be anytime between 1980-1993, but info on these specific models is really hard to find. The late 90s model the LX50/LX50K are easier to find.

Look at this sad excuse for a crossover tho.. :lol:


It's attached directly to the back of the external cable clamps. The wires aren't even soldered to the speaker terminals, just held on by clasps..

Here's a better picture of the driver setup.


I really think they have a lot of hidden potential, and I wouldn't expect it to cost more than maybe $150-175 for 2 sheets of NoRez, wooden braces, and a custom crossover. Maybe $200 if i go with tube connectors also.

S Clark

  • Volunteer
  • Posts: 6302
  • a riot is the language of the unheard- Dr. King
Re: Upgrading vintage speaker internals?
« Reply #2 on: 20 Feb 2020, 05:16 am »

But I was curious if it would be worth doing some internal upgrades?


Or is this just a case of "If it ain't broke, dont fix it"?
You asked so you get an honest answer. 
To the first questioin... the answer is no.
To the second, I'd suggest that the assumption that "it ain't broke" is probably overly optimistic, and it almost certainly isn't worth the several hundred bucks to redesign and upgrade the crossover.  It looks like the woofer is playing completely unfiltered, and very little if any control on the midrange as well.
Sell it on Craigslist and put your money in something better. 
Build a <$200 GR-Research kit, or any other well reviewed kit and you'll be much happier... Hope this free advice is worth at least what you paid for it.  :thumb:

Hobbsmeerkat

  • Full Member
  • Posts: 644
Re: Upgrading vintage speaker internals?
« Reply #3 on: 20 Feb 2020, 06:13 pm »
Thanks I appreciate an honest answer!
It was a fun thought, but it would definitely take getting some proper measurements to build a working crossover, and with the fact that they're probably 30ish years old, and not designed with quality in mind, there's probably not much that can be done. lol
And considering that they were likely $100 for the pair, new, it would be foolish.. lol

I definitely plan to get a pair of A/V3 or X-Statics once we're ready to make a more dedicated movie/music room in the next year or so. But i wont be selling them as dad plans to move them into his bedroom.

Well, my dad got them for free, so free advice on free speakers is okay by me! lol

rollo

  • Industry Participant
  • Posts: 5008
  • Rollo Audio Consulting -
Re: Upgrading vintage speaker internals?
« Reply #4 on: 20 Feb 2020, 07:23 pm »
  Great for the Garage system. Ya probably could improve somewhat just with some stuffing.


charles

Hobbsmeerkat

  • Full Member
  • Posts: 644
Re: Upgrading vintage speaker internals?
« Reply #5 on: 19 Mar 2020, 10:12 pm »
I decided to look around online, & found some similar options on Parts express for cheaper. 3 sheets of a norez-type foam, and some speaker gasket foam. I also already had a dynamat-like product from another project I used to dampen the rigning from metal driver frames.







I don't plan to upgrade the crossover, its not going to be worth the expense without also just rebuilding the cabinet altogether.
But i will be adding a few wooden braces in some spaces to further dampen the cabinet.
Its made for a fun, and fairly easy afternoon project!

nickd

Re: Upgrading vintage speaker internals?
« Reply #6 on: 19 Mar 2020, 11:44 pm »
Put inexpensive poly caps in that crossover and you might be surprised at the difference.  Those old electrolytic caps might be dried out. Fun, easy and not too expensive to try.

Hobbsmeerkat

  • Full Member
  • Posts: 644
Re: Upgrading vintage speaker internals?
« Reply #7 on: 19 Mar 2020, 11:52 pm »
I certainly could! Perhaps at a later date, and maybe even replace that sand-cast resister for good measure. lmao

But so far, it's helped clean up the low end & mids a bit, they seem to be less muddy and boomy, esp at higher volumes. I'm pretty happy with how it's working tbh.