• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Speaker just started sounding blown out at low frequencies (LTV university 200 312)

R

red888

Active Member
I have 2 LTV university 200 312 speakers in an old stereo cabinet and the right one just started to sound a little blown out at very low frequencies. While I was looking at it I also noticed the wiring to the receiver was wrong, asked about that here fyi: https://audiokarma.org/forums/index.php?threads/are-my-speakers-wired-wrong-fisher-400.1080212/. Probably not related though.

After messing with the speaker wires, swapping them, etc I can confirm its not the receiver or the speaker cable. And now the speaker sounds even worse :(

I removed the speaker from the cabinet and its pretty pristine but when I push on the cone gently it sounds really scratchy.

I don't have an oscilloscope or multimeter and I don't have any knowledge of audio equipment myself. A part from getting it repair professionally is there any low hanging fruit here I could try? I'm not sure how to detach the back it doesn't look like its screwed on.

Would it damage the speaker if I played it outside of the cabinet at lowish volume to troubleshoot it?

EDIT
-----
Looking at it I do see foam cracked. Could that be the issue? Could I fix that myself?
1739989927228.png
 
Last edited:
Register to hide this ad
The cracked foam is probably the cause. Not sure where you would get parts for an LTV University speaker.
I'm guessing that's the spider that is cracking.
I think we need more, better pictures to see the full extent of the damage.

I did a Google Search for LTV University Speaker Parts and found this on an old Polk speaker forum:
mhardy6647 February 2012 - https://forum.polkaudio.com/discussion/129497/anyone-know-about-ltv-university-speaker-company


LTV (Ling-Temco-Vought - a conglomerate who once made aircraft) bought University Sound (from White Plains NY). At some point, University and Electrovoice were merged - not sure under whose ownership. Today both brands belong to Telex. Fortunately for us, Telex maintains an excellent free on-line resource of documentation.

http://archives.telex.com/

The Sphericon tweeters are pretty good. The Diffusicone 12 is a reasonable extended-range driver. Should sound OK and be quite sensitive; "great for tube amps".

The best on-line resource for vintage University consumer drivers and speakers (pre-LTV, but it will still be helpful to you) is
www.hifilit.com
specifically, http://www.hifilit.com/hifilit/University/University.htm

Finally, you can also find info on University drivers and speaker systems in late 1950s through early 1960s Radio Shack general catalogs! Scans are available on line at www.radioshackcatalogs.com (another wonderful resource)

EDIT: For example, take a look at pages 52 through 54 of http://www.radioshackcatalogs.com/catalogs/1961/
 
Thanks so much for the info! If its just the foam could new foam just be glued on? I'm assuming thats a tremendously ignorant question haha.

They sound really nice I'd love to keep them. Could a professional carve out a foam replacement and fix it?

Here are more pics. To my untrained eye its super clean. Probably the first time its been removed from the cabinet in 60+ years:
1739991289714.png
1739991321401.png
1739991386414.png
 
I'm just gonna take it to a repair place, but I do have another question, how does the "brilliance" knob separate? Its connected to the cabinet back panel via a hole drilled for it. I can't for the life of me figure out how its connected. Im afraid of trying to just pull the knob off because its pretty on there. Any ideas on how to remove the knob so I can get it off the panel? I can't find any documentation or examples online.

1739995773009.png
 
Honestly you could just peel that foam off and suck any remaining bits with a crevasse tool and a vacuum. It's only there to keeps bits from getting into the voice coil. You can use the "two spoons" method to pry the knob off. Just put a spoon on each side of the knob and pry against the backing plate.
 
@red888

Is the Brilliance know still attached to the cabinet? Will you please post a picture of it?

You are very smart to be concerned about breaking it.
 
red888 said:
I removed the speaker from the cabinet and its pretty pristine but when I push on the cone gently it sounds really scratchy.:(
Click to expand...

Can you describe this further? When you push gently, does the cone feel scratchy or as if it is binging up a little?

I should note that I don't know this particular speaker, but I feel we can adequately troubleshoot it for you.
 
@Lucky Pierre I gave it another firm-ish tug and it appears it does just come off. So that mystery is solved. Just adding a photo for reference:
1740060392149.png

When I gently push down on the cone I don't know if it "feels" scratchy but it definitely sounds scratchy. Also, I did just remove the foam, it was totally disintegrating- maybe pieces of it got into the cone, could that be the cause?

I'm still gonna take it to a tech in a few days but anything I can investigate myself would be super helpful and edifying, thanks!
 
@red888

A quick test that might help is to reinstall the driver in the baffle, but at 180 degrees from the way it came out. Sometimes the spider can sag, causing a voice coil rub. By rotating the driver you may alleviate some of the sag.

If you really have a bound up voice coil you probably need it reconed. You don't say where you are. You if you are in the US, you might want to consider sending it to MillerSound. Bill is a speaker wizard. You might want to also consider having both reconed at the same time, or you can wait to see if they sound different after getting this one fixed.

These are super cool speakers and, IMO, worth the cost to get them repaired properly. Will you post pictures of them in the cabinets?
 
Yes, Mark where the top of the woofer was mounted and remount it 180 degrees to help with "Cone sag".

I've cleaned a few speaker gaps by holding the speaker face down and playing some bassy music.

A little blow with a compressed air can get the foam bits out (Careful).

Pushing on the cone should be "Silent".

Press near the edge at the 12 - 3 - 6 - 9 clock positions.

If it rubs more at one position that's the location that should be mounted at the bottom.

Hope that helps.
 
@Buck Rogers "Pushing on the cone should be Silent"- Its WAYYYYY not silent at all. Even the slightest push I get that sandy/scratchy sound. So I can play this driver outside of the cabinets at low volume? ie like you said put it face down and play sound through it to try to push some of the junk out?

@Lucky Pierre I'd post a pic of the whole console but this is my burner inet user haha. Its this beautiful oversized Lane credenza. I've yet to find it online so its unique enough that I'd rather not share. I get the impression a lot of these things were custom-ish jobs or limited runs because they all seem pretty unique.
 
Press near the edge at the 12 - 3 - 6 - 9 clock positions.

Does it scratch in one position more than the others?

This also can happen if the woofer is overpowered and the voice coil de-laminates from the coil former.
 
@Buck Rogers it seems practically anywhere I press I get that scratchiness. voice coil repair is super expensive if even possible right? I know it varies but any ballpark on that? I frequently see these speakers on ebay anywhere from $150 to $400 for two working ones. Hate to pay that much to repair one, is it worth it?
 
I'm leaning more towards a de-laminated voice coil which is Re-cone only.

Doesn't help that they are super rare. This is the first one I've seen, Not sure if it's 10" or 12"?

Another problem is the tweeter needs to be removed for repair.

And if someone Could re-cone the parts will probably look and sound different.

I know a guy that took a similar type speaker carefully Cut the cone off, Re-wound the voice coil and reassembled it.

Dicey work.

That said Coaxial is a big plus in sound, Phenolic tweeter another plus.

You could buy another pair and then have a spare.

There are many new high performance HiFi coaxial speakers out there at about the same price,

But then your stuck in speaker design Hell!

s-l1600.jpg
 
Here is a killer looking Coaxial found on the bay. 200$ pr.

Eminence coaxial horn speaker

Problem is old cabinets are not made for the demands or designs of modern drivers.

They are not as stiff or as well sealed and definitely not as highly tuned as modern speakers.
 
Buck Rogers said:
I'm leaning more towards a de-laminated voice coil which is Re-cone only.
Click to expand...
I an with you here. This sounds like the same thing that happened to one of my Wharfedale Super 12s. I sent that single one to MillerSound to be reconed. Bill did a fantastic job. In retrospect, though, I should have done both. I can here the difference between the two drivers.
 
@Buck Rogers if those Eminence 1680s don't have the right cabinets will they sound like ****? Also, I'm assuming the fisher 400 can handle them without issue right?

If its unrepairable can you recommend a good replacement pair of drivers? The cabinets are pretty solid wood and built for 12" obviously. I'm not an audiophile, but I really liked how these sounded. I wanna say they sounded "warm" as people say vintage speakers do, but what the hell do I know. I just wouldn't want to get new speakers that sound sterile or even too "clean" if that makes sense. Kinda want a little lack of precision/muddiness cause it matches the vibe and also means they don't have to be as high end/expensive.

Theres a pair of 312s on ebay now for $380 obo (seems like a lot?). Looks like they have been _totally_ restored: https://www.ebay.com/itm/226525319643?itmmeta=01JMMY8Z9RYPCA75JG1XYEVP9F&hash=item34bdf611db. I don't know what a reasonable ask is for them.

I just don't want to downgrade, maybe a small upgrade would be cool.
 
You must log in or register to reply here.
Back
Top Bottom