To Dope or NOT
- Thread starter Grid
- Start date
Grid
Active Member
Hello, the leads were soldered directly to the voice coil then to the lugs and insulated washers on the speaker. You know, I almost saved this speaker. I carefully reached into the speaker with needle noses and got hold of the washer that was loose in there and I got it out the hole, but I wasn't gentle enough. The voice coil lead got caught with the washer and a rip happened. I tried to connect what was left of the voice coil lead to the lug with JB Weld and repaired the rips. To no avail.
Thank you. I've had enough of this. Let's just forget it. I have to live with ruining a 50 year old working tweeter with my clumsiness to have let it drop in the first place. But that's what happens when you FORCE a job you dob't have ample bench space to do. I'll do the other one but I'll use the damned bed as a bench and move the soldering station over there. And as I said, I luckily purchased for $50 another exact working set of these speakers; so I'll have tweeters galore and will part out the rest.
Thank you again. And just to get back on topic, I will redope the Utah woofers.
Grid
Active Member
Wow, that is tremendously nice of you. Thank you! But let's wait on that for now. As I say I have another set of these speakers coming and I'll install the tweeter and should be good to go. Then I'll part out the rest. Thank you again.
Post pictures of the set when you get them. The leftover set could be turned into an ewave. Definition here http://audiokarma.org/forums/index....esign-collaborative-econowave-speaker.150939/
Grid
Active Member
Hmmm, never thought of that. But that is probably because I have so little room in this shoebox apartment, that I automatically think, get rid of excess stuff, part out and recoup investment, as I live on a meager fixed income. When there's no room to work, projects become more aggravating than rewarding. And I got piles of stuff on shelves I'll probably never get to. Ironically, I have not figured out yet where I'm going to permanently place these Utahs. Right now they are on the floor and I have to remember to wlak over them or stub my toes. That's how packed I am in my own home. But I certainly will think over the ewave idea. Thank you!
I know normally eBay links are not permitted. But since this is no longer an active listing, I think it would be allowed so that you can see the speakers. It is said, the configurations with the horns were Utah's best. By the way, I paid $50 not $75. https://www.ebay.com/itm/Vintage-Ut...nsion-RARE-HORN-LOADED-MIDRANGE/253431201225?
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Grid
Active Member
Thank you, I might just end up doing that for practicality. I have no room in this apartment. It has choked my hobby almost to a halt but I think I can tuck away the drivers. I had thought of selling them to recoup some of my investment, as I exist of a fixed income. But Utahs are sleepers. Prolly wouldn't get $10 for one, LOL. Normally eBay link are not allowed. but since the listing is no longer active, I think it would be OK to link you so you can see the speakers. I paid $50 not $75. Could have gotten them for $35 but that's another story of my screwing up things. https://www.ebay.com/itm/Vintage-Ut...nsion-RARE-HORN-LOADED-MIDRANGE/253431201225?
Grid
Active Member
I just did a, "Now wtf is wrong!?" I neatly recapped the other speaker while I wait for the dope Monday. It played for three seconds then I heard clipping, then nothing. OK, turns out an amp fuse blew. Replaced fuse, everything is playing fine now but don't turn up the volume much!
I'm learning a great deal here. This is interesting... with the old caps, I could turn up the volume much higher. And remember, the tweeter was not getting juice. OK, so I can only theorize. This Advent 300 amp is (manufacturer) rated at 15 wpc. The speaker, 36 W. But I only had this one speaker connected. Does the fact that there was no load on the other channel play into why this is clipping and blowing the fuse? Was I somehow getting all of the amp's 30 watts combined going into this one 36 watt speaker?
I'm learning a great deal here. This is interesting... with the old caps, I could turn up the volume much higher. And remember, the tweeter was not getting juice. OK, so I can only theorize. This Advent 300 amp is (manufacturer) rated at 15 wpc. The speaker, 36 W. But I only had this one speaker connected. Does the fact that there was no load on the other channel play into why this is clipping and blowing the fuse? Was I somehow getting all of the amp's 30 watts combined going into this one 36 watt speaker?
Is this the receiver? http://davidreaton.com/advent/model_300_receiver_main_page/
Grid
Active Member
Yes, indeed, that's it. You know, I should mention, my Advent has never been serviced. Maybe there's an issue with the amp, as someone pointed out early. The only other amps I have are 130W and 75W.
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Grid
Active Member
Update: Just hooked up the speaker to my Sansui AU-7900, with four times the watts than the Advent 300. Speaker plays fine--and loud--and so does the amp. No blown fuses. As a precaution, I only did this for about half minute. I next hooked up the Advent 300 receiver to my Advent speakers (OLA). Again, no problems, loud and clean, even to 2 O'Clock.
Why does the Advent blow a fuse only when connected to this speaker? Before the recap, it wasn't blowing a fuse. If there is something wrong with my recap, why does the more powerful Sansui play these speakers with no issues?
Why does the Advent blow a fuse only when connected to this speaker? Before the recap, it wasn't blowing a fuse. If there is something wrong with my recap, why does the more powerful Sansui play these speakers with no issues?
Grid
Active Member
Roy at Asylum was suggested to me.
leftfielder
Active Member
All this talk on dope on the surrounds gots me a thinkin. I'm a Polk SDA owner and have doped their cones and butl surrounds I think. F
leftfielder
Active Member
Sorry, machine went nuts and this is a redo. If certain makers back in the day used dope on their surrounds as a guess to prolong their life then why not on the cones themselves and I have evidence being done also back in the day. I do own '87 Polk SDA 2Bs and just touching the cones there is a undeniable stickiness to them. One of the mid drivers that got replaced w/ a new Polk driver also has dope on the cone as all the older ones. I tried to see if any thing was added to the butyl surround but were clean of any substance. So does one dope the entire driver if not intended by the builder or he/she just never tried it to see if it lasts longer and just preforms somehow better ?
Oh, just in case you dudes never knew this to clean your Polk drivers use Original Windex ONLY. not new and improved, no other cleaner just Original Windex.....Lew
Oh, just in case you dudes never knew this to clean your Polk drivers use Original Windex ONLY. not new and improved, no other cleaner just Original Windex.....Lew
Grid
Active Member
Well, I'm just a lowly layman, but cones are of course paper, whereas the surrounds of KLH, AR, Utah, etc were cloth. I can only theorize, the sealant was used not only for durability but to give the cloth a "rubbery" vibrating quality which would conduct bass frequencies.
StimpyWan
Addicted Member
The dope was a sealant, as you guessed. Being acoustic suspension, the speakers wouldn't perform properly without the dope. The cloth surrounds would be too porous otherwise. Plus, I expect the dope would affect the Q of the woofer as well, tuning and tightening bass response.
