Anyone know anything about Ling Electronics?

[iomegaman]

Specifically a Ling electronics EPN-10-C???

It seems to be a variation of an MEQ5...

just picked one up for $25.00...weighs a ton...apparently the coils are pretty beefy...I'll post some picks...looks exactly like these on Reverb:

https://reverb.com/item/8401985-pair-of-fully-adjustable-1956-tube-ling-electronics-midrange-equalizers-power-supply-pultec-meq5

Its some sort of tube EQ...

"The Q controls how wide the curve is from very wide bell to a sharp spike while the height controls the amount of boost (up to 40db). Next is the "Q" booster in case you need more than 40dB of Boost! The manual suggests this control be used sparingly if at all! Next the center control is three concentric knobs for fine tuning frequencies. The next knob is also fine tuning for frequencies so you can really hone in a frequency. The last concentric knob is for selecting peak, notch, or off, and for range of frequency selection in three ranges from 30Hz to 100Hz, 100 Hz to 500 Hz, and 500 Hz to 3,500 Hz. The equalization is not limited to these frequencies, with the other controls the 20 to 100 goes from 2 Hz to 1,200 Hz, the 100 to 500 goes from 30Hz to 2,000 Hz, and the 500 to 3,500 goes from 200Hz to over 5,000 Hz" (according to the seller on Reverb who sold a pair)...

I found a manual on eVilbay for $75.00 gonna see if it contains a schematic...looks like I need to reverse engineer a PSU for it somehow...maybe someone somewhere nows something...?

 

[iomegaman]

Here's some of my pics...

Tubes are GE 6SJ7/ TungSol 6SN7 GTB/(Input side)...same on output but add a 12AU7

 

[iomegaman]

Inside with the coils...

Pics same as reverbs...just used theirs...

 

[Bo Deadly]

Very nice. I love old inductor capacitor EQs. They age well and are easy to work on even without a schematic.

It shouldn't be too hard to come up with a supply for that. Personally I would just put SPMS+chokes in a floor box with the right connector. That would be the path-of-least-resistance to see it work.

My only reservation is that it's a lot of controls for one filter. Clearly it's a lab filter. You would only be fiddling with maybe two of what looks like about 9 controls. But at least you can now say you have a piece of gear with a triple concentric switch in it.

 

[Brian Roth]

I've never seen a Ling unit, but seeing the label with "Ling Altec" rang a history bell with me:

https://en.wikipedia.org/wiki/Ling-Temco-Vought

"In 1956 Ling bought L.M. Electronics, and in 1959 added Altec Electronics,"

https://en.wikipedia.org/wiki/Altec_Lansing

"James Ling purchased the Altec Lansing Corporation from the ailing George Carrington, Sr., in 1958. By the time James Ling spun Altec Lansing off in 1974, his company, LTV-Ling-Altec, had heavy debts."


Bri

Adding a personal PS....

After reading the entries about Ling-Temco-Vaught a fond memory comes to mind.  My Dad and Grandad were execs with a petroleum company in Okla. City and would chat about various business news while Young Brian <g> would hang out with them.  Looking at the timeline from Wiki, I suspect the conversation was about Ling (and his Texas cohorts which all sounded a bit shady to me at the time, thanks to their remarks) purchase of the Wilson Meat company, which had a packing plant in OKC, adding yet another company into the conglomerate.

One or the other of my elders deadpanned, "I heard that Ling bought AT&T today and renamed it as Ring-a-Ling Telephone Company."

It still seems a bit funny to me....but maybe ya hadda be there!  <g>

 

[emrr]

That looks like a typical notch filter with a very narrow bandwidth.  Used for test/measurement, not audio originally.    I've had a few various makes, none were good for anything audio.  Haven't seen his one before. 

 

[iomegaman]

I've never seen a Ling unit, but seeing the label with "Ling Altec" rang a history bell with me:

https://en.wikipedia.org/wiki/Ling-Temco-Vought

"In 1956 Ling bought L.M. Electronics, and in 1959 added Altec Electronics,"

https://en.wikipedia.org/wiki/Altec_Lansing

"James Ling purchased the Altec Lansing Corporation from the ailing George Carrington, Sr., in 1958. By the time James Ling spun Altec Lansing off in 1974, his company, LTV-Ling-Altec, had heavy debts."


Bri

Adding a personal PS....

After reading the entries about Ling-Temco-Vaught a fond memory comes to mind.  My Dad and Grandad were execs with a petroleum company in Okla. City and would chat about various business news while Young Brian <g> would hang out with them.  Looking at the timeline from Wiki, I suspect the conversation was about Ling (and his Texas cohorts which all sounded a bit shady to me at the time, thanks to their remarks) purchase of the Wilson Meat company, which had a packing plant in OKC, adding yet another company into the conglomerate.

One or the other of my elders deadpanned, "I heard that Ling bought AT&T today and renamed it as Ring-a-Ling Telephone Company."

It still seems a bit funny to me....but maybe ya hadda be there!  <g>

That is actually kind of funny...I grew up in Oklahoma and my grandfather worked for GE there...I remember the Wilson packing plant...also back in the day when riding in the car to my grandparents house passing the stockyards...some smells you never forget...

Seems like JBL was in OKC as well at one point...

I picked up this notch filter at a new surplus place here in Tucson...probably out of an avionics development or something...Tucson has a lot of airplane bones...

 

[ombudsman]

I've got an LTV Ling line amp in non working state that needs some help. I have a friend that works on gear but he couldn't figure it out. Maybe it's somehow not for normal audio purposes, but it does have a conventional looking input transformer (and no output transformer) and is not terribly complicated (maybe a little more inside than I would have guessed, though).  It looks well made and is all discrete.  Anybody know of a tech who might be familiar with this or up for a mystery ?

 

[Brian Roth]

That is actually kind of funny...I grew up in Oklahoma and my grandfather worked for GE there...I remember the Wilson packing plant...also back in the day when riding in the car to my grandparents house passing the stockyards...some smells you never forget...

Seems like JBL was in OKC as well at one point...

Altec had a plant in OKC located at what was once University Sound.  They quit making speakers and focused on electronics, including making Electrovoice branded products.

Bri

 

[Bo Deadly]

If it's good enough for a laboratory it was probably state-of-the art for the time which from looks of it is a few tubes and an LC filter. If the heater wires are neatly tucked, I should be quiet enough.

If the notch wide enough it could be good for metal guitar and the controls suit that function.

Just stumbled across this from "Official Gazette of the United States Patent Office Vol 742 May 1959" buried in Google Books:

 

[PRR]

https://patents.google.com/patent/US2888526

 

[emrr]

bingo. 

 

[Bo Deadly]

https://patents.google.com/patent/US2888526

For posterity, this appears to be the Ling Electronics EPN-10 schematic:

 

[mjrippe]

Late to the party here, but I have seen a few Ling pieces in person and yes, they are very much lab audio equipment.  There is a tube graphic EQ that is a massive electro-mechanical beast and goes something like 2Hz, 4Hz, 8, 16, etc.  Others have 0.1Hz, 0.2Hz...  Really well built and probably cost a fortune, but not super useful for studio work.

 

[nielsk]

Re-wire the inductors to useable LRC passive EQs and re-purpose the tubes into a make up stage...