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DMR NYC
2008-01-20, 18:10
I have a wonderful set of old speakers from a long-defunct manufacturer, Spica. The speaker model is the TC-50. They are about 20 years old, and are very neutral in their presence, delivering lovely reproduction in my Manhattan apartment.

Unfortunately, one of the tweeters has blown, and now I am faced with the choice of saying goodbye to my old friends and getting a new set of primary speakers, or somehow finding a replacement tweeter and an audio repair shop that can handle the fix for me.

Any suggestions are most welcome.

The rest of the setup: SB3 and a NAD amplifier.

Thanks, David

swhite58
2008-01-20, 18:22
A quick Google got me to here:

http://spicaspeakers.com/repair/spica-drivers.php

It discusses options for replacements etc

Shane

dadster
2008-01-21, 20:18
The drivers turn up occationally, you just missed a set of early tweeters on ebay. Madisound does sell a 4 ohm Polydor/Audax replacement tweeter but it is unlcear if it a better match for early TC-50 or late TC-50i units.

Another good resource, other than the kind link to my site above :-) is the Spica Lovers User Group (SLUG)
http://tech.groups.yahoo.com/group/britststr/

I always try and post to the SLUG forum when I find drivers on ebay.

gordon
2008-01-21, 20:38
I also have a pair of TC50s, and I had to replace a tweeter about 1 year ago. I ordered my replacement from madisound (just use their search feature to search for TC50). The tweeter and their service were both great.

A few things to keep in mind:

1. The original tweeter will be glued or caulked in place, so once you remove the screws, you'll have to pry it out.

2. As stated on the above-mentioned web site, the terminals are positioned differently on the replacement tweater, so I had to open up a gap in the cabinet using a rasp so that the tweeter would slide in. Don't make the gap any bigger than necessary as the box will need to be air-tight when you are done.

3. Make sure you observe the polarity when you solder in the new tweeter- the terminals should be color coded, although you'll have to look closely.

4. You should caulk the tweeter in addition to screwing it in place. I used 100% silicone sealant (the permanently flexible type in case I ever need to replace it again - available at home depot).

My speakers now sound as good as new!

(BTW, I also am using an NAD amp and an SB3.)

zanash
2008-01-22, 06:00
these are very fine speakers and worth the effort to replace the tweeter.

try contacting wilmslow audio [uk] they are normally very helpful and can normally off a suitable replacment. I would advise that you need to change the matching tweeter in the other speaker too ...as it will have had a long life and will not match the new unit fitted.

dadster
2008-01-22, 07:48
these are very fine speakers and worth the effort to replace the tweeter.

try contacting wilmslow audio [uk] ...I would advise that you need to change the matching tweeter in the other speaker too ...as it will have had a long life and will not match the new unit fitted.

I agree - replacing both is important!

David -- just curiuous, you are obviosuly happy with your new tweeters. Are yours early TC-50s(retangular hole in the felt) or late TC-50i (square hole) units?

gordon
2008-01-23, 20:46
I agree - replacing both is important!

David -- just curiuous, you are obviosuly happy with your new tweeters. Are yours early TC-50s(retangular hole in the felt) or late TC-50i (square hole) units?

I imagine you intended to ask me that question rather than David. My TC50's have the square hole, so I guess they are TC-50i's, although the plate on the back just says TC-50.

One other thing, I agree that Spica made a point of matching tweeters and that matched tweeters are supposed to be an important reason why TC-50s sound so good. However, unless you buy a matched pair, replacing both tweeters won't accomplish this. As far as I know, the only way to match tweeters is by testing a bunch and then pairing up the tweeters that have similar frequency responses. If Madisound offers matched tweeters, their web site doesn't say so. Does anyone know whether they offer matched tweeters?

As it happens, I only replaced one tweeter and am quite happy with the resultant sound.

DMR NYC
2008-01-23, 21:56
Thank you all for your replies. I will follow up and post accordingly, although it may be several weeks before I have the time to focus on this project.

Gordon, it's good to find someone else out there with similar ears!!

Interestingly, I thought someone might post about a reasonable replacement for these speakers. Instead, what I seem to be reading is that I have had a mighty fine pair of speakers for the past two decades!

gordon
2008-01-23, 23:10
Well, best of luck with your repair job. I'm interested to hear how it comes out!

dadster
2008-01-24, 09:08
Yes, Gordon sorry, so aside from having to modify the cabinet a bit, it sounds like you were happy using the Madisound tweeter with the TC-50is - this is good to know!

Spica used a specific model of tweeter used in the 50 and a different on the 50i. The one Madisound sells isn't one of those, and the same tweeter presumably wouldn't work well both places. Spica changed tweeter models because production issues with the woofer used in the 50, made them move to a new model, used in what was dubbed as the 50i (BTW - TC-50is are not marked as such, you can only tell by the square tweeter hole, although the change took place about s/n 7500)

Now to shift gears a bit, Spica did closely match components, they measured each cap, resistor, etc and the woofers response curves were individually characterized (see service codes) make certain that the left and right were matched. However, this was not true for the tweeters. Tweeters had enough uniformity that individual matching wasn't necessary within a given model.

please reference:
Spica Drivers: http://spicaspeakers.com/repair/spica-drivers.php
Service Codes: http://spicaspeakers.com/repair/spica-service-codes.php

DMR NYC
2008-01-24, 17:20
Yes, Gordon sorry, so aside from having to modify the cabinet a bit, it sounds like you were happy using the Madisound tweeter with the TC-50is - this is good to know!

Spica used a specific model of tweeter used in the 50 and a different on the 50i. The one Madisound sells isn't one of those, and the same tweeter presumably wouldn't work well both places. Spica changed tweeter models because production issues with the woofer used in the 50, made them move to a new model, used in what was dubbed as the 50i (BTW - TC-50is are not marked as such, you can only tell by the square tweeter hole, although the change took place about s/n 7500)

Now to shift gears a bit, Spica did closely match components, they measured each cap, resistor, etc and the woofers response curves were individually characterized (see service codes) make certain that the left and right were matched. However, this was not true for the tweeters. Tweeters had enough uniformity that individual matching wasn't necessary within a given model.

please reference:
Spica Drivers: http://spicaspeakers.com/repair/spica-drivers.php
Service Codes: http://spicaspeakers.com/repair/spica-service-codes.php

The only information I have left is a bottom portion of the serial number, which seems to be either "13125" or "13725" with a "B' afterward, and a service code of "H3.9-12."

Can I tell from this information whether these are 50s or 50i's? (My recollection is that they are probably the former, but it's been too long to be certain.)

dadster
2008-01-24, 20:40
The shift from 50 to 50i was about s/n 7500. With 13,000 series numbers you definately have 50i's. The felt hole surrounting the tweeter should also be square (early 50s were rectangular)

DMR NYC
2008-01-25, 05:24
So, will Madisounds' tweeters fit the 50i?

dadster
2008-01-26, 13:26
The tweeter Madisound sells is not a drop-in replacement, but from Gordon's experience it sounds like he was happy with the results in his TC-50i's. The physical differences of the tweeter are discussed on my pages.

My suggestion: If you have further Spica questions read the information compiled on my website or go to the Spica Lovers User Group as it is likely the most appropriate place for this discussion and the community most knowledgeable to help.

SLUG: http://tech.groups.yahoo.com/group/britststr/

gordon
2008-01-26, 20:06
So, will Madisounds' tweeters fit the 50i?

They should. I've got the 50i's, and, with a minor modification to the cabinet (I had to make a little slot with a rasp because of the terminal), these tweeters fit fine. Per the earlier suggestions from Dadster et al, you should probably replace both tweeters. I did not, but, based on Dadster's explanation, I probably should have.