My Newest Fascination: Audiologic By Randix Mini Hi-Fi Components

Bloodhound

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Nov 5, 2019
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About a week ago I made an off the cuff stop at the local Goodwill. After looking for cassettes I headed straight back to the electronics graveyard in the back of the store. They tend to keep it fully stocked often piling things up on top of one another 2-3 layers thick. After giving everything a quick once over and doing some digging I noticed two small components I'd never seen before. One was an Audiologic By Randix LX-40A amplifier and the other was an LX-52T tuner. I picked up the very small and thin amp first and was shocked at how heavy it was.. at least 7-8 lbs. Knowing there was something to these units I purchased both for $10.39 plus tax. After doing some research I learned that they are from two different bookshelf systems sold in the early 80's.

I hooked up the amp and noticed tons of static from the volume switch and a completely dead right channel. Using the skills I've learned here on the forum I located one bad solder connection on the amp chip to the board and reflowed it. The volume pot as well as balance, bass and treble pots were clamped together so I carefully peeled back the clamps and gave them all the deoxit treatment. When all was said and done it just blew me away. I am in complete shock at the power this thing puts out. It's comparable to larger amps without a doubt. It's crystal clear and the volume switch is extremely sensitive and responsive as are all the others.

Has anyone had any experience with these units? There's very little information about them online. I'd like to complete both systems with their missing components. Here's a couple "file photos" I grabbed off the web for reference purposes...

vintage-audiologic-randix-lx-40a_1_aab92ee8a0c1bad7395ebe6f5c2fd9e3.jpg

AUDIOLOGIC-AM-FM-Stereo-Tuner-LX52T-vintage-excellent-condition.jpg
 

Reli

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Dec 24, 2010
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Yeah those were some unique units, especially the ones labelled for vertical use.
Here's a list of all the components. I believe the 52 and 62 series had a bit more power.
LX-40A mini-amplifier, LX-40T mini-tuner, MG-40E equalizer
LX-52A mini-amplifier, LX-52A mini-tuner, MG-52E equalizer
LX-62A mini-amplifier, LX-62T mini-tuner, MG-62E equalizer
LX-500 turntable
LXR-720 digital amplifier/tuner
MX-500 mini speakers
 

Bloodhound

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Nov 5, 2019
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I've been spending my free time researching these components and systems. You really have to dig online to find information but it's out there. I'm going to do my best to compile some here for anyone interested. Here's my "collection" that has grown over the last 3 months...

image0.jpegimage1.jpegimage3.jpeg
 

Bloodhound

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Nov 5, 2019
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Cool aren't they? Glad you appreciate them!

Let's start with the Audiologic By Randix LX-40A premain amplifier and LX-40T tuner vertical units.

My research has determined that these units were manufactured in JAPAN from 1980-1982 and imported and sold in the US by Randix Industries LTD, Milford MA. The following information was collected from various sources including Radiomuseum.org, Wikiboombox etc.

"Audiologic by Randix" was apparently an American electronics distributor who imported products from Asia during the late 70s and 80s, and re-sold them to various department stores like Zayre, Lechmere Sales, Caldor, and Bradlees. Some of these were also branded Weltron."

LX-40A premain amplifier:

Manufacturer / Brand:Randix Industries LTD, Milford MA
alternative name
Cosmo Communications Corp; CDN
Year: 1982 ??Category: Audio Amplifier or -mixer
Semiconductors (the count is only for transistors)Semiconductors present.
Main principleAudio-Amplification
Wave bands- without
Details
Power type and voltageAlternating Current supply (AC) / 120 Volt
Loudspeaker- For headphones or amp.
Power out
from Radiomuseum.orgModel: Audiologic Stereo Premain Amplifier LX-40A - Randix Industries LTD, Milford
MaterialMetal case
ShapeBook-shelf unit.
NotesRandix LX-40A Audiologic Stereo Premain Amplifier;
85 W power consumption. Made in Japan.

According to High Fidelity magazine 1980 (Page 67) the LX-40A premain amp and matching LX-40T tuner were available as a set. Purchase price was $299.95
High-Fidelity-1980-Components.pdf (worldradiohistory.com)

High-Fidelity-1980-Components - Copy.jpg


Vintage-AudioLogic-by-Randix-Micro-Stereo-System-LX-40A-LX-A40T.jpg

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As you can see they really "packed it in there." The Amp chip is HUGE!

p1010001_598616.jpg

The LX-40A and LX-40T were also sold outside the US under the WELTRON brand model numbers A-3100 (Amp) and T3000 (Tuner). One interesting difference between them however is a difference in amplifier power consumption. The LX-40A uses 85 W as opposed to the A-3100 which consumes 43 W.

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Now, Reli's previous post got me digging deeper...

Edited "Here's a list of all the components. LX-40A mini-amplifier, LX-40T mini-tuner, MG-40E equalizer."

In all my research I have been unable to find any information or pictures concerning the MG-40E equalizer. I may be completely wrong but I'm beginning to believe it didn't exist. I spent several days/hours looking and digging and found absolutely nothing. Unfortunately, this hunch was further supported by an ad from High Fidelity Magazine listing the Audiologic By Randix equalizers available at that time.

Audiologic Equalizers.jpg

Be that as it may, there are several assorted pictures on the web of both the Audiologic and Weltron branded versions of the Amp and Tuner with various associated components. And just in case your interested, there's a set available on ebay right now! Vintage Audiologic LX-40T And LX-40A | eBay
One thing I will say is that you won't be disappointed if you can get your hands on a set. Mine impress me more and more every day!

To Be Continued...
 

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Phil3p0

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Apr 20, 2021
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Just joined to share in your enthusiasm. I have the LX-52A amp, LX-52T tuner, LX-52E equalizer and TCD-25 tape deck. The amp and tuner are working well, but when I connect the equalizer I get a 60hz hum that I can’t figure out.
The tape deck needs belts, but it seems ok otherwise.
Theres nothing quite like these components is there, the amp drives my Pioneer HPM-100s as well as any normal-sized equipment
 
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Bloodhound

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Just joined to share in your enthusiasm. I have the LX-52A amp, LX-52T tuner, LX-52E equalizer and TCD-25 tape deck. The amp and tuner are working well, but when I connect the equalizer I get a 60hz hum that I can’t figure out.
The tape deck needs belts, but it seems ok otherwise.
Theres nothing quite like these components is there, the amp drives my Pioneer HPM-100s as well as any normal-sized equipment
That's Awesome Phil! My efforts weren't in vain posting all this stuff LOL! Glad to share your enthusiasm. Your right in that they are unique. Built like tanks to! I'll bet your Pioneer speakers sound great and well powered! My deck needs belts as well. I found it NOS in the box never used. Belts were goo of course. I couldn't find anything online as far as replacements go so I'll have to use the wire measuring trick and order them by size.

I had the same issue with my eq. Have you tried cleaning all the switches with deoxit? Did the trick on mine. I'm missing two knobs so I hope to find another one on the cheap to use for parts if needed. Post some pics when you can! Looking forward to seeing your setup! :)
 

Bloodhound

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Nov 5, 2019
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Weird, yours say made in Japan, but I've seen others saying made in Taiwan.
Hey Reli! Good observation. The vertical units were made in Japan and the horizontal in Taiwan. Not sure why they moved production with the later horizontal models. I can tell you that they perform beautifully regardless. You'd be shocked.
 

RobertoRS

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Sep 14, 2021
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GDL Mx
Hi everybody !
I just found this forum and joined it. I had have the system LX-52A mini-amplifier, LX-52A mini-tuner, MG-52E equalizer also the Tape system (not have the code at hand right now). This system was a 15 yr birthday gift from my Mon. It was just amazing back at the 80´s. I conserved the system althoug not the amp is not working because volumen knob, but Now I am triyng to repair the Amp since the Volumen potentiometer was changed by a no expert technician. I realized it is a B50k 8 feets or pins (Linear potentiometer) correct me if Iam wrong. But as the coper circuit is dammaged. I am searching the schematics diagrams in order to be eble to rebuild the tracks, If enyone know where can I found It I appreciate Your help. I have ordered the potentiometer at AliExpress so I have few time as I wait it to arrive.
Forget to tell The system was made in Taiwan.

If there is a chance to post some pics from the circuits at the Volumen Potentiomer and tracks so I can see the details and may comparer it to find out the configurations may be a chance...

Thank You in advance.
Best Regards.
Roberto RS.
 

Bloodhound

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Nov 5, 2019
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Hi Roberto! Welcome to the forum. Great story and read about you receiving the system as a birthday gift! Sorry to hear your LX-52A isn't working. It can be difficult to undo someone elses shoddy work. Can you post a picture of the damaged copper circuit? Perhaps a jumper wire can be used assuming you can follow the tracks? As for a schematic I have been unable to find a service manual so you may be out of luck. I could open up my unit for you and share a picture of the intact circuit if it helps. lemme know!
 

RobertoRS

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Sep 14, 2021
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Hi Roberto! Welcome to the forum. Great story and read about you receiving the system as a birthday gift! Sorry to hear your LX-52A isn't working. It can be difficult to undo someone elses shoddy work. Can you post a picture of the damaged copper circuit? Perhaps a jumper wire can be used assuming you can follow the tracks? As for a schematic I have been unable to find a service manual so you may be out of luck. I could open up my unit for you and share a picture of the intact circuit if it helps. lemme know!
Thank You for answer me, well I have a picture right at the circuit were the Volumen potentiometer used to conect, were the pins connect to the circuit that is damaged; they did a kind of cable bridge tu reconnet the potentiometer. the fact is that they replace the potentiometer with another one (no original were available ); I mean they did a mess saddly. Passing the years now I could order one Lineal potentiometer class B50K ( Lineal ). It will take few weeks until It arrive hopfully. So here is the picture. Is right the right corner upside down were the volumen knob is connected.
If you need a pict of the hole circuit, I can have it and post, no problem.

I appreciate Your kind attention and help.
Best Regards
Roberto.

1632593822569.png
 

RobertoRS

New Member
Sep 14, 2021
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GDL Mx
Hi Roberto! Welcome to the forum. Great story and read about you receiving the system as a birthday gift! Sorry to hear your LX-52A isn't working. It can be difficult to undo someone elses shoddy work. Can you post a picture of the damaged copper circuit? Perhaps a jumper wire can be used assuming you can follow the tracks? As for a schematic I have been unable to find a service manual so you may be out of luck. I could open up my unit for you and share a picture of the intact circuit if it helps. lemme know!
Hi, more details of the problem... is regarding to the right channel wich is not audible. The STK459 was repalced that time, now I followed a test to check if the amp was ok; for instance, take messures of the outputs currents, just turn the amp on, not playing, speekers disconnected then at the outputs should be 0 volts AC. I did it and it was Ok. So back to the Volumne Potentiometer wich has to be changed and rebuild the circuit tracks as well. Another point to review might be the balance potentiometer ( now I remember I did ) well I´ll double check it.
The Equalizer must be cleaned and see if get better; The Tape recorder need new band as well, the Turnable is not working I haven´t had the chance to check it up. The tunner is the Only system part that is working good =).

Any suggest or Idea I´ll appreciate.
Best Regards.
Roberto RS.