SI 5066 Input Cap Option

Some of you may be way ahead of me on this one. I ordered some Panasonic 16v 1 ufd surface mount FILM caps Monday. Arrived today, look like the Siemens stacked film and foil I use in leaded package.
I am going to stack two to get a 2 ufd coupling cap for my 5066. The sonics have to be better than the multilayer ceramics now used.
The package is 1210 so it is larger than the stock 805 type used by SI. I have used the size on a board before to mount a 4.7 ufd ceramic cap.
The part number at Digikey is PCF1132CT-ND. The Panasonic part number is ECP-U1C105MA5. They are about 50 cents each. If you search it shows a 2000 part minmum. Oder and you can order any number in multiples of 10. All these size caps are sold in 10 packs.
Mounting two of these will be a breeze compared to using a normal film cap or BG. May work out to be as good sonically.

George
 
Panelhead said:
Some of you may be way ahead of me on this one. I ordered some Panasonic 16v 1 ufd surface mount FILM caps Monday. Arrived today, look like the Siemens stacked film and foil I use in leaded package.
I am going to stack two to get a 2 ufd coupling cap for my 5066. The sonics have to be better than the multilayer ceramics now used.
The package is 1210 so it is larger than the stock 805 type used by SI. I have used the size on a board before to mount a 4.7 ufd ceramic cap.
The part number at Digikey is PCF1132CT-ND. The Panasonic part number is ECP-U1C105MA5. They are about 50 cents each. If you search it shows a 2000 part minmum. Oder and you can order any number in multiples of 10. All these size caps are sold in 10 packs.
Mounting two of these will be a breeze compared to using a normal film cap or BG. May work out to be as good sonically.

George

George, I'm just curious about how you get the larger surface mount caps to stick to both pads. I tried soldering the larger size X5R's on a couple of boards but could only get contact on one pad. I tried moving them around while soldering with no luck. Eventually I gave up and connected them to small leads.
 
Re: Re: SI 5066 Input Cap Option

Jumpin John said:


George, I'm just curious about how you get the larger surface mount caps to stick to both pads. I tried soldering the larger size X5R's on a couple of boards but could only get contact on one pad. I tried moving them around while soldering with no luck. Eventually I gave up and connected them to small leads.




I first tinned the end caps of the capacitor. Then set down on one pad. Then move down to get contact on the other. The ceramics transferred the heat well enough to melt solder at both ends.
The capacitors used were 4.7 ufd ceramic in a 1210 package. You can also twist them so they are crooked.
Doing this was a bit bit of a pain so I went to 805 package. But it gives me a chance to try plastic film over the ceramics. May be easier to order some 0.68 ufd that are in a 805 package. Two in parallel would get the - 3db point down to 12 Hz. It should be flat to 50.

George
 
Re: Re: Re: SI 5066 Input Cap Option

Panelhead said:





I first tinned the end caps of the capacitor. Then set down on one pad. Then move down to get contact on the other. The ceramics transferred the heat well enough to melt solder at both ends.
The capacitors used were 4.7 ufd ceramic in a 1210 package. You can also twist them so they are crooked.
Doing this was a bit bit of a pain so I went to 805 package. But it gives me a chance to try plastic film over the ceramics. May be easier to order some 0.68 ufd that are in a 805 package. Two in parallel would get the - 3db point down to 12 Hz. It should be flat to 50.

George


Thanks George, I may give it another try if I feel ambitious. One advantage that the larger cap may have is the fact that I can actually see it with my aging eyes. What theoretical advantages would a film cap have over a good electrolitic such as a BG? I found some gargano film and foil caps (4.7 uf) at a local electronics surplus store. The manufacturer is unknown. They are big ( approx 1"x 1.5") and yellow with SF on the side. Initially I thought that they gave the amp a slightly more forward sound, but I have not had much time to play with it since.
 
Pics

Next time I mod a board I will take a couple pics. The size limit here is a pita. Usually takes me longer to post pics than mod a board.
To keep from damaging the traces, try a 12 watt or less iron with pencil tip. I really think tinning the end caps of the SMDs first makes this much easier.
The input caps are C3, C4. These are all the SMD that I have changed on the boards.
The C11 and C12 are the 0.1 ufd cSMD caps bypassing the power pins of the chip. I have never changed these, just added a medium value low impedance electrolytic across. I have used UHE Nichicon and FM Panasonics. Somewhere 220 ufd to 330.

George
 
A paralleling input cap upgrade question

Hi, Im currently running 2 stock SI's bi-wired in parallel to some Wharfedale diamond 9.6's they are 90db sensitivity, and sound pretty amazing, easily blowing away my crappy all in wonder mini systems, except for the obviously lacking bass at higher volumes.

I plan on modding my two T-amps and putting them into one box with a single stereo pot (alps blue?) and all 8 outputs.

I also wanted to upgrade the input caps C3/C4 to improve the bass. My question is, does this need to be done on both amps. because one will drive low frequency and one highs (no active pre here) would there be sonic benefits to keeping small cap size for the dedicated higher range amp?

Besides RCA ins and upgraded binding posts this will be the only major update on the board itself i plan for these amps. I have 2 more waiting as backups/further mods in the future.

In regards to the capacitors to be used, i am a bit of a novice, and would appreciate if someone could tell me which will be the easiest for upgrading C3/C4 and a part number, i would really appreciate it, I have read the posts on this subject, but can't determine which is best for me.
FYI I have some 10uf 16V caps on hand but don't know if this would be too big. And I will be powering via an 12V SLA Coleman powermate jumpstarter with two car lighter outlets that I have adapters for plugging the SI into. (Its what I have on hand)

Thanks for the help, any and all input is appreciated, especially a few pics of the upgrade to C3/C4! That could change my life.

W
 
In regards to the capacitors to be used, i am a bit of a novice, and would appreciate if someone could tell me which will be the easiest for upgrading C3/C4 and a part number, i would really appreciate it, I have read the posts on this subject, but can't determine which is best for me.

I think the easiest method is to use poly caps and mount them off the board - unless you don't have enough room in your enclosure. Also, it's a little easier to solder this than SMD parts. I followed the mod from panomaniacs website. I used 2uF Solens that I had lying around. It sounds good to me.
 

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