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PreCd
11-05-2011, 12:55 PM
I am just finishing up on the TL 2B mod for my SDA 2Bs and am wondering about the polarity on the new tweeters. I need to change one of the small spades to large but which one is it? Black wire or white wire?

F1nut
11-05-2011, 01:02 PM
Black

gimpod
11-05-2011, 01:19 PM
Sorry Jesse but it's the white one (Ground)

F1nut
11-05-2011, 01:26 PM
Thank you Tony, you're correct.

PreCd
11-05-2011, 01:31 PM
Shifting topic a bit here but I have another little problem possibly. Upon completing the installation of my 5.8uf cap I checked it with a multimeter. I cannot get a reading on it. It meters ok on ohms but nothing on uF mode except the standard OL reading. All the other caps on the board check good. Any suggestions?

gimpod
11-05-2011, 01:33 PM
Your welcome Mr. Jesse :cheesygrin:

gimpod
11-05-2011, 01:37 PM
Shifting topic a bit here but I have another little problem possibly. Upon completing the installation of my 5.8uf cap I checked it with a multimeter. I cannot get a reading on it. It meters ok on ohms but nothing on uF mode except the standard OL reading. All the other caps on the board check good. Any suggestions?

Are you checking it in circuit or out of circuit, if in circuit remember that cap is being bypassed by a resistor.

PreCd
11-05-2011, 01:42 PM
In circuit. Is this normal then? Sorry if that sounds like a stupid question but pretty new to this.

gimpod
11-05-2011, 03:06 PM
This is most likely your problem. Ideally you should check component values out of circuit and by them self's. You could just remove the cap and check it.

BTW There are no stupid questions for the most part, If you don't know you don't know and should ask.

PreCd
11-05-2011, 04:53 PM
Thanks gimpod. I took the 5.8uf Sonicap out of circuit and it checked exactly 5.8uf. Put it back in and I am getting no reading on it so would the resistor knock it out like that? I went ahead and installed the crossover and things sound good on the one speaker. The other is next. Here is what I did:

Un-installed the old resistor replacing it with a 2.7k 15watt Mills. Installed per F1nut's instructions (R2 hole and "G")
Installed 5.8uf Sonicap putting one end into the top "C5" hole and the other in "H"
Replaced the polyswitch with a .9amp polyswitch (I listen loud sometimes so better safe than sorry).
Left the old bypass in there to see our it sounds, figured I could always take it out if needed.
Replaced the other caps.




This is most likely your problem. Ideally you should check component values out of circuit and by them self's. You could just remove the cap and check it.

BTW There are no stupid questions for the most part, If you don't know you don't know and should ask.

gimpod
11-05-2011, 05:50 PM
Thanks gimpod. I took the 5.8uf Sonicap out of circuit and it checked exactly 5.8uf. Put it back in and I am getting no reading on it so would the resistor knock it out like that?

Yes.


Un-installed the old resistor replacing it with a 2.7k 15watt Mills. Installed per F1nut's instructions (R2 hole and "G")
Installed 5.8uf Sonicap putting one end into the top "C5" hole and the other in "H"
Replaced the polyswitch with a .9amp polyswitch (I listen loud sometimes so better safe than sorry).
Left the old bypass in there to see our it sounds, figured I could always take it out if needed.
Replaced the other caps.

This doesn't sound right. To begin with that resistor should be a 2.7 Ohm not a 2.7k and should be installed in holes B and G, R2 should have a jumper there. That 5.8uF cap is fine where it's at. Just go ahead and remove that old bypass cap (C4) as it's not needed with that 12uF Sonicap (C3).

F1nut
11-05-2011, 06:26 PM
Tony, I think and hope that Kevin simply wrote that info incorrectly and in fact it is a 2.7 ohm, 12 watt mills. I do know that instead of using B, he used the unused hole in R2 and retained the jumper.

PreCd
11-05-2011, 06:51 PM
Oops! Yes F1nut is correct it was 2.7 OHM resistor. Sorry about that and thank you for keeping up with me. My fingers got ahead of my head.

One more question. Does it matter which lead the P and R go to from the circuit board to the voice coil? I thought I had it licked and knew exactly where it went then I had a uh oh moment.

Thanks.

Kevni


Yes.



This doesn't sound right. To begin with that resistor should be a 2.7 Ohm not a 2.7k and should be installed in holes B and G, R2 should have a jumper there. That 5.8uF cap is fine where it's at. Just go ahead and remove that old bypass cap (C4) as it's not needed with that 12uF Sonicap (C3).

gimpod
11-05-2011, 07:04 PM
Oops! Yes F1nut is correct it was 2.7 OHM resistor. Sorry about that and thank you for keeping up with me. My fingers got ahead of my head.

One more question. Does it matter which lead the P and R go to from the circuit board to the voice coil? I thought I had it licked and knew exactly where it went then I had a uh oh moment.

Thanks.

Kevni

No problem my brain has a hard time keeping up with my fingers too.:lol:

No it doesn't matter on the leads from P & R. BTW it's an inductor (Big round thing the board mounts to) not a voice coil.:wink:

PreCd
11-05-2011, 07:06 PM
Awesome! Well it is done. And I have put on some music to test. Dianna Krall live in Paris. Should tell me a little about the love I give them.

Thanks for your input and help.

Kevin



No problem my brain has a hard time keeping up with my fingers too.:lol:

No it doesn't matter on the leads from P & R. BTW it's an inductor (Big round thing the board mounts to) not a voice coil.:wink:

gimpod
11-05-2011, 07:09 PM
Your welcome just glad I could help.

inspiredsports
11-06-2011, 12:59 AM
As a heads up, you may not be happy right away as Sonicaps can take a while to blossom.

Not apples to apples I know, but just today I dropped a 1 ohm 12 watt Mills and 13.5uf Sonicap into just the left speaker of my son's Monitor 5jr+'s. For the first couple of hours the left side sounded bad. After seven or eight hours things were better, but still not as good as the untouched right channel,

PreCd
11-06-2011, 01:19 AM
I can see a large improvement already so that is good news. I believe much of my problem was the poly switches. Over the past 24 years I have had these speakers I cannot count the times I have tripped them. My previous amp was not suited for these speakers and I just a few months ago purchased a amp that would drive the SDA 2Bs, a Adcom GFA-555. I replaced the Polys today because I do like it louder at times. Probably hurts my sound some but it is insurance for me.

Have all the caps for the GFA-555 and preamp so they are next on the list.

The TL2B sounds good at this point and again I am glad to hear that they will only get better.

O and by the way I did not go with all Sonicaps all around. The electros got replaced with the same from Erse and the 12uf got a Erse Pulse X capacitor. I also left the bypass cap in there just to see how everything went. I just could not justify putting that much money into the Sonicaps even though I can see the quality difference between them and the Erse. I did put the Sonicap in the 5.8uf slot though and used the Mills capacitor.

Thanks for all your advice.


As a heads up, you may not be happy right away as Sonicaps can take a while to blossom.

Not apples to apples I know, but just today I dropped a 1 ohm 12 watt Mills and 13.5uf Sonicap into just the left speaker of my son's Monitor 5jr+'s. For the first couple of hours the left side sounded bad. After seven or eight hours things were better, but still not as good as the untouched right channel,