GPX 990 - full tear down & clean

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Lasonic TRC-920

Moderator
Well, if you saw my thread "Two Boxes coming today (WHERE IS UPS???) UPDATED!" http://www.boomboxery.com/forum/viewtopic.php?f=2&t=5147 Then you saw the GPX 990.

This is a big box, 20cm (8 inch) speakers. I think it has a great classic design, lots of chrome in the right places. When I bought this box, I knew it would need work, some repair and a full cleaning.

Here's what I started with. Dented speaker grills (why did them make protruding grills. These were destined to get dented)
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Well, there's no time to waste. I pulled the back cover and gutted the box. If there is one positive side of this model it's a very easy tear down. Maybe 12 screws inside and it was empty.
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Not really to much to it.
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And straight into the sink with it. For the most part it was very clean inside. It did have a thin layer of dust on the bottom, but that was about it.
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Gotta clean the inside too!
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I'd like to thank Bill Larson for vandalizing this box with his signature! Thanks dick, you had to use a marker? REALLY?
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SPOTLESS!
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With a little scrubbing I managed to remove the Graffiti on the back! I used some rubbing alcohol.
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Now for the face....I had to get out the pall-peen hammer and a block of wood to lightly hammer out the speaker grills. You can't even tell they had dents.
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The face of the box cleaned up really nice. There are still some wear spots, but it really looks good.
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I used Simonize Chrome Polish on all the chrome surfaces and they came out SWEET! They just had a bit of dirt on them. Nothing was pitted.
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The tuner Plexiglas and the aluminum control panel are in great condition. All the screen printed dial information is flawless.
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Time to do a bit of wiring, getting everything back were it belongs in the wiring holders to prevent vibration. Boomboxery member TRC-911, whom I bought this from had installed speakers from the Lasonic TRC-931. NICE!
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Speakers back in, cassette door back on.
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Face plate back on....getting really close now. At this stage I did some testing...making sure everything was working....just need to polish the knobs.
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And back together....Ready for a full test...Powered Up with AC power cord: CHECK, Powered up on batteries: CHECK, Radio: CHECK, Line In: CHECK, Mono/Stereo/Wide: CHECK, VU Meters: CHECK, Balance/Trebal/Bass: CHECK, Volume: CHECK. Looking Good!
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Had to get a picture with the VU Meters rockin'
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So there you have it....The GPX 990 fully clean. I do have some work to do on the cassette deck, needs a few things. BUT the line in works great and I have been listening to it the whole time while writing this. I guess I better get over to the "What Boombox Are You Cranking Up Right Now??" link...

Next up...a full clean of the Lasonic TRC-918....Stay Tuned!
 

Terry

Member (SA)
I'd like to apologies for my uncle Bill writing his name all over it.

Us Larsen's aren't normally such vandals.
 

Gluecifer

Member (SA)
My love affair of wanton desire for this box begins NOW!

That's a really spectacular job you've done there Chris, exemplary!

And very nice driptip porn with the jauntily placed sponge on the back of her case.

Complete boxtease shot that one!

Now you need to do some reviews of the sound and performance of her too!

Best of luck with the TRC-918 too brother.



Rock On.
 

Lasonic TRC-920

Moderator
Terry said:
I'd like to apologies for my uncle Bill writing his name all over it.

Us Larsen's aren't normally such vandals.

Oh that's OK, it just means he loved this box very much and didn't want anyone to steal it! :lol: :lol:

sony_apm_fan said:
Loveit. Love it. Love it. Did I say I love it? :yes:

And the work in progress photos too. Love them. :yes:

It is a good looking box. Classic design. Yeah, I like to follow those threads when people take them down and put them back...so I thought I would do the same.

nz boom said:

Thank You Thank You

devol-toni said:
:w00t:

That is the big MF, wow....., I liked :yes:

Nice cleaning job man, congrats :thumbsup:

Yes, this thing I HUGE. It's probably about the size of a Lasonic TRC-931. I will take pictures today of it next to my GF-777Z.

Gluecifer said:
My love affair of wanton desire for this box begins NOW!

That's a really spectacular job you've done there Chris, exemplary!

And very nice driptip porn with the jauntily placed sponge on the back of her case.

Complete boxtease shot that one!

Now you need to do some reviews of the sound and performance of her too!

Best of luck with the TRC-918 too brother.

Rock On.

Well, I'm not going to tell any lies....While the sound is clean on lower volumes, it doesn't seem to have much punch when you get on the knob. I still need to Deoxit the knob pots. But I'm not sure if having 16 om speakers from the TRC-931 is effecting it's performance. I will have to ask that question in the Tech section to see if anyone knows what were in here and what om they were.

But, tearing it down and putting it back together fixed some rattles and everything is tight and of course it looks great! I'm happy to have it in the collection.

Thanks everyone for the on going support as always!
 

MasterBlaster84

Boomus Fidelis
Beautiful job on the cleanup and repair, she looks great. :thumbsup:

I've never had one of these apart but I'd be willing to bet the original speakers were in the 4 ohm range but the box sure looks good with those big white speakers. :yes:
 

TRC-911

Member (SA)
Now I wish I hadn't sold it :-P

:thumbsup: :thumbsup: :thumbsup: :thumbsup: GREAT JOB CHRIS!!! :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup:

I'll start searching fir the tape buttons and see what I can find :)
 

Fatdog

Well-Known Member
Staff member
I've always imagined that those boomboxes sound like Prosonic PQR-9962s. Whether they do or not, I have no idea. :blush:

Great job, Chris!!
 

Lasonic TRC-920

Moderator
TRC-911 said:
Now I wish I hadn't sold it :-P

:thumbsup: :thumbsup: :thumbsup: :thumbsup: GREAT JOB CHRIS!!! :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup:

I'll start searching fir the tape buttons and see what I can find :)

Hey Chris, If you can find the "Eject" button and one of the "Player" buttons, that's all I need. I found one of them jammed inside the case when I opened it! I really am going to try to get this cassette working. So far, all my "Notable" radio's have working cassettes and I have a MASSIVE cassette collection!

One thing is for sure....your saying "When it comes to smooth transactions, you can't miss with Chris" is right on the money....thanks again for all your hard work shipping these out to me!
 

Lasonic TRC-920

Moderator
Old school Scott said:
Love the bath pictures,
That GPX has some resemblence to this Lloyds[ Image ]

Cheers OSS :afro:

Hey Scott, I saw that Lloyds on another thread and I thought the same thing. It has some obvious external features that look the same like the tweeter bezels, speaker rings, tuner cavity and handle positioning. But when I had the GPX apart there were quite a few mounting posts that were not being used. I can only assume this is a generic box frame used by many companies of the time. Very interesting though.

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