More fun refurbishing audio stuff

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Dave
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Re: More fun refurbishing audio stuff

Post by Dave »

But, a Myth is as good as a mile!
Typeminer
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Re: More fun refurbishing audio stuff

Post by Typeminer »

Dave wrote: Tue Sep 25, 2018 11:00 pm But, a Myth is as good as a mile!
And a straight line is the shortest distance between two puns.

(Bless you again, Spider!)
Saccharomyces cerevisiae is the linchpin of civilization.
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Re: More fun refurbishing audio stuff

Post by Bookworm »

Typeminer wrote: Wed Sep 26, 2018 6:21 am
Dave wrote: Tue Sep 25, 2018 11:00 pm But, a Myth is as good as a mile!
And a straight line is the shortest distance between two puns.

(Bless you again, Spider!)
Something's Mything from that statement. Like... A sneeze.
I'll get a life when it's proven and substantiated to be better than what I'm currently experiencing.
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jwhouk
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Re: More fun refurbishing audio stuff

Post by jwhouk »

No, it's a myth, a MYTH!

"Yeth?"
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Re: More fun refurbishing audio stuff

Post by lake_wrangler »

TazManiac wrote: Tue Sep 25, 2018 10:56 am- Upgrade the Media PC's storage and bring it forward into more everyday use. (Truthfully It's a crappy/scrappy dual-core w/ built in 5.1 and an antient video card that outputs SVHS to a big ass'd CRT TV...) W/ an video card upgrade I might go HDMI... :o

I'm soooo behind the Cutting edge, well, it actually IS funny...
You know, I only just got rid of my CRT TV last summer, when I moved... My dad gave me a flat screen TV a few years ago, but I had not taken the time to do the switch. When I moved, I finally set up the flat screen TV in my new home. I put my old TV up for sale on Kijiji, and someone was interested. But when I brought it to him, it turned out that the old TV had a scratch on the screen. So he wanted to forget the whole thing, but still pay me something for my fuel for bringing the TV to him... I suggested he just keep it anyway, to use it until he could find something better. Honestly, I had never even noticed the scratch before, so it obviously wasn't affecting the image all that much... He did end up keeping it, which is a good thing, because there just wasn't any room for it in the new house...

My cell phone is a LG Stylo 3 Plus... model came out a year ago, and is fairly low end... And I am NOT using it to "keep connected" to all the social media...

My cable box is an old, outdated one, one that is no longer supported by the cable company...

My laptop, until recently, was an old Acer Travel Mate that originally came loaded with Win XP... (I only just this month updated to a refurbished Dell Latitude 5285 2-in-1 convertible... 8GB of RAM, a Core i5 7300 CPU, and a 256 GB SSD)

My computer is an AMD FX 4100 processor... it's already several years old (CPU-World says the series launched in 2011...)

My DSLR camera model (Canon EOS 40D) came out in 2007, which is rather ancient, in the digital camera world...

My truck is a 1991 GMC Suburban...

My bicycle is a fairly recent vintage, however... 2012, in bicycle terms, is not all that old.

But yeah, you're not the only one behind the technological curve... :mrgreen:
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Dave
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Re: More fun refurbishing audio stuff

Post by Dave »

Had a bit more fun with a simple refurbishment job recently. At the flea market a couple of weeks ago I came across a KLH Model 200 table radio... a two-box stereo AM/FM system that Kyocera built back in the late 1980s when they owned the KLH brand name. The seller wanted $20, said that it mostly worked but that the volume control wasn't reliable. For the price I said what-the-hell... I've been wanting a decent bedside radio with an alarm-clock function.

It did need some work... a bit of epoxy inside to repair a broken mounting clip for the front PC board, and a good cleaning of all the controls for starters. This didn't fix the volume problem... the sound kept cutting in and out... and I eventually figured out that the output-muting relay had worn-out contacts.

A new relay arrived from Digi-Key, I soldered it in yesterday evening, and clean sound has been restored!

I don't know if I'll do anything to the speakers. They're decent little paper-cone pleated-surround drivers, about 4", not really showing any signs of age, in mostly-sealed compartments made of thin fiberboard. I'm sure they could be improved but I don't know if it would be worth the time and trouble... they serve the needs pretty well as they are.
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TazManiac
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Re: More fun refurbishing audio stuff

Post by TazManiac »

Daaaaaaaave!
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Dave
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Re: More fun refurbishing audio stuff

Post by Dave »

Dave wrote: Fri Apr 26, 2019 11:59 am I don't know if I'll do anything to the speakers. They're decent little paper-cone pleated-surround drivers, about 4", not really showing any signs of age, in mostly-sealed compartments made of thin fiberboard. I'm sure they could be improved but I don't know if it would be worth the time and trouble... they serve the needs pretty well as they are.
Well, I couldn't resist the urge to fiddle. After listening to the KLH for a while I decided that the speakers probably deserved an upgrade. I ordered a pair of 4" full range drivers from Parts Express... some positively-reviewed poly-cone house brand (Dayton) whose specs suggested that they would work OK in the small KLH cabinetry.

Lucky choice... the results are very nice indeed. Installation was easy... they're basically a drop-in replacement. The sound is clearer, more balanced and musical... no deep bass of course, but what's there is clean and boom-free. The system now sounds like a compact stereo music system rather that like a clock radio with pretensions of grandeur :D Our local classical-music station just finished playing "Concerto Fantasy for 2 timpanists and orchestra" by Philip Glass... a very nice test that the modified KLH passed without any distress at all.

These inexpensive ($13 each) drivers are good enough to make me wonder how they'd sound if you put one or two of them into a quarter-wave transmission line enclosure. Might make a very nice music system for a small apartment or dorm room.
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Re: More fun refurbishing audio stuff

Post by TazManiac »

(as has been before, and lily will be again; Paraphrased from another post)-

Wapsi Square: Come for the Boobs, Stay for the ... (in this, and most cases, stuff to find out more about).


I've been kind of laying low on Audio/Video interests as I try and ramp up the career side of things, time to 'Level Up' as the kids used to say.

Still, I have a few things on the back burner, and it's always good to hear from real people and their real life chances they took and how it worked out.

Danka...
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TazManiac
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Re: More fun refurbishing audio stuff

Post by TazManiac »

Evaluating whether I'm going to refurb a pair of these: http://www.humanspeakers.com/e/epi200.htm

EPI 200, they include a Tweeter & an 8" Mid/woofer, and a 12" passive radiator on the bottom.

I already have a pair of 'Really Big Ol' Speakers!!!', but another pair wouldn't hurt.
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Dave
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Re: More fun refurbishing audio stuff

Post by Dave »

TazManiac wrote: Wed Nov 13, 2019 2:51 pm Evaluating whether I'm going to refurb a pair of these: http://www.humanspeakers.com/e/epi200.htm

EPI 200, they include a Tweeter & an 8" Mid/woofer, and a 12" passive radiator on the bottom.

I already have a pair of 'Really Big Ol' Speakers!!!', but another pair wouldn't hurt.
From what I've heard, I suspect that this would definitely be worth the effort. The EPI speakers had/have a good reputation for natural sound.

As I understand it, their design philosophy was to stick with a very simple crossover mechanism (often just a simple high-pass capacitor for the tweeter) and to depend on the woofer's natural high-end roll-off to create a flat frequency response.

What do they seem to need? New surrounds on the driver(s)? Maybe a replacement/upgrade for the crossover cap? (15-16 uF is easily achievable with polyester-film caps - could be a good upgrade if the originals are electrolytic and have dried out over the years).

A bit of light sanding, a wipe-down with tung oil, and you'd probably end up with something that looks as nice as it sounds.

(The ham repeater group I'm a part of has a pair of old, donated EPI speakers in the storage locker, awaiting some time for refurbing... I think they need new surrounds on the woofers. I'd buy 'em from the group and do it myself, but I no earthly place in the house to put 'em.)
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TazManiac
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Re: More fun refurbishing audio stuff

Post by TazManiac »

Dave wrote: Wed Nov 13, 2019 5:03 pm
From what I've heard, I suspect that this would definitely be worth the effort. The EPI speakers had/have a good reputation for natural sound.

As I understand it, their design philosophy was to stick with a very simple crossover mechanism (often just a simple high-pass capacitor for the tweeter) and to depend on the woofer's natural high-end roll-off to create a flat frequency response.
Yeah, I'm not yet into the insides yet & there is a three position switch on the back of each that tosses either a cap and/or a coil/cap combination into the mix.

There is mention made of the characteristics of the mid-woofer naturally rejecting high frequencies on it's own...[/quote]
What do they seem to need?
Every surround is shot, and one of the tweeters looks to have fallen back in (maybe it was unscrewed and is just in the cabinet...)

I'll take pictures.

The cabinets themselves look decent enough though.
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TazManiac
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Re: More fun refurbishing audio stuff

Post by TazManiac »

PS- It'll have to wait a couple of weeks, so please lower expectations.
:)

I'm thinking the 12" Passive Radiators on the bottom might get away w/ just new surrounds, and maybe the mid-bass 8"-ers too, but I'm pretty sure there are brand new tweeters in my future...
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Re: More fun refurbishing audio stuff

Post by Just Old Al »

OK, guys. I recently picked up an Akai M8 (tube) reel to reel tape deck. Lovely beast, and essentially new. Hell, the thing still had the plastic slip bags on the speaker covers. I used to have an M9 in the rebadged version - the Roberts 771X. Loved that thing.

I was impressed for 20 bucks.

However, the capstan pressure roller is as hard as a carp and has a divot in it from sitting in the same spot for decades....not great. For initial testing it’ll do, but a recommendation on a replacement tire would be good. Even if I have to take something from another machine and make a new wheel/bearing for it that’s all good - machine tools y’know.

Going to give it a good clean and try it when the belts get here and see where I end up. Recommendations gratefully received, though.
"The Empire was founded on cups of tea, mate, and if you think I am going to war without one you are sadly mistaken."
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TazManiac
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Re: More fun refurbishing audio stuff

Post by TazManiac »

When I'm doing refurbs on HP printers (for example) I'm struck by the difference in Pickup Rollers, (very similar in composition to Tape Deck stuff).

In the 'olden days' the rollers were a small axle core and a lot of 'rubber' material, these days they are more Plastic Barrel w/ a thin 'rubber band coating of grippy stuff wrapped around it.

Overall diameter wouldn't have changed but the inert vs active material ratio has. This sort of option might open up more opportunities for retrofitting, in your case.
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Just Old Al
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Re: More fun refurbishing audio stuff

Post by Just Old Al »

TazManiac wrote: Mon Nov 18, 2019 3:36 pm When I'm doing refurbs on HP printers (for example) I'm struck by the difference in Pickup Rollers, (very similar in composition to Tape Deck stuff).

In the 'olden days' the rollers were a small axle core and a lot of 'rubber' material, these days they are more Plastic Barrel w/ a thin 'rubber band coating of grippy stuff wrapped around it.

Overall diameter wouldn't have changed but the inert vs active material ratio has. This sort of option might open up more opportunities for retrofitting, in your case.
That's a very nice idea...distinctly possible. Even an aluminium one would be simple to do. thanks - nice thought. Any idea on a souce for the tires?
"The Empire was founded on cups of tea, mate, and if you think I am going to war without one you are sadly mistaken."
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Dave
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Re: More fun refurbishing audio stuff

Post by Dave »

Some years ago I needed to replace the paper-traction "tires" on an HP flat-bed plotter. Like the capstan roller on your tape deck, the existing rubber had dried out, hardened, and had a divot from sitting pressed against the metal drive-wheel for years.

Direct replacements were unobtainable.

What I ended up doing, was stripping all of the old rubber off of the metal core, and then covering the core with a piece of silicone-rubber tubing. The stuff I found (and used) is sold as fuel tubing for model airplanes... transparent with a bluish color to it (fluoresces in UV I believe). It's quite flexible, seems to be fairly strong, and was made to resist fuels and solvents (and so probably pretty stable in the face of home-type air pollutants such as ozone). It was stretchy enough that I had no real difficulty working a piece of it onto the old metal core of the traction roller, and it's soft enough that it "grabbed" the paper quite effectively (no slipping).

I got it at a local hobby shop... they had a bunch of different diameters.

If you need a diameter that they don't have, check out McMaster-Carr. They have dozens of kinds of industrial tubing, including oil-resistant Buna-N and various silicones.

They also carry drive rollers... you might get lucky and find one which would be close to a drop-in replacement for your capstan pressure roller.
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