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Old 16th February 2005, 06:40 PM   #21
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Quote:
Heh. I'm probably with you right there. I'm sort of modding these things just to mod 'em.. Take them to their "max", even if I can't necessarily hear the difference
Lol, exactly! Bigger, better, faster...... doesnt really matter "why". Plus, its a great way to learn.
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Old 16th February 2005, 10:30 PM   #22
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Originally posted by theAnonymous1


Lol, exactly! Bigger, better, faster...... doesnt really matter "why". Plus, its a great way to learn.

Yup. I'm still learning though. I've got a ton of gainclones to put together. I have most of the boards done, now it's just chassis/power supply work that needs to be completed.

I'm using the SI as my learning experience. I'd rather work on a small board like this and get used to all the problems I'll run into with casework, etc., than go full bore into drilling some of the nice enclosures I have and screwing them up!
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Old 21st February 2005, 03:10 PM   #23
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Default Found Problem

Found out last week why my amp was not working. The output wires had pulled out. The sticky stuff was holding the offending wire in place, but no continuity.
There are links to pics over on audiocircles. The new chokes really seemed to make the 5066 sound bigger and more powerful. Gonna try aircored choked in my next one.

George
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Old 22nd February 2005, 05:33 AM   #24
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How did the rest of the mods go? Mine are still in process. I ran into some problems with the SMD resistors not measuring correctly after soldering.
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Old 22nd February 2005, 11:10 AM   #25
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Default Try this

Quote:
Originally posted by motherone
How did the rest of the mods go? Mine are still in process. I ran into some problems with the SMD resistors not measuring correctly after soldering.

The rest went fine. But I only swapped C3/C4 on one and did them and removed c1/c2 on the other.
I did not change the resitors. The gain is fine as is, about the same as the Le Monstre and Mini Aleph.
The values of the factory resistors were closer than 1%. I checked and rechecked to verify continuity after cap replacement.
My method for SMD part swapping is to use soldering braid and a 15 watt pencil tip. It is be layed on top of the SMD and after about 10 - 15 seconds the part comes up when lifting off the braid.
Then heat and retouch with solder the mounting pads. Not much solder will stick to these tiny pads. Lastly tin the electrodes on the SMD part. Hold in place with a pair of small tweezers and usually the chip gets hot enough to resolder at both ends when hit with the iron at only one.
This is why ceramic caps are needed. The polys would cook to death if this size and hit with an iron long enough to mount.
The metal film resistors should not change value that much if soldered in quickly. If you are not tinning the electrodes try it first, and remeasure value after before installing.
The input caps and new output inductors have made a big improvement in sound quality. There is real bass output now. The sound is just bigger, more power, better dynamics. No downside noticed yet sonically.

George
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Old 22nd February 2005, 07:11 PM   #26
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Thanks.. I'll try tinning it. The first board has the following mods done on it:

Removal of C1/2/3/4, with the DC blocking caps positions jumpered. Removal of L1/L2, with their positions jumpered as well. Swapped feedback resistors for 20k.

I'll try resoldering the resistors again as you mentioned. I actually opened up a new thread on this in the electronics section.. I don't know if I'm just doing this with an iron that's too hot or what (mines adjustable, and at the lower end of the range, it won't even melt the solder).

I also swapped the electrolytic for a 1000uF panasonic FM. On my second board, it'll have the same mods, but with 2x 1000uF FM, soldered directly to the chip (fun experiment in lead bending).

I think for my second amp, I'm going to do it without a volume control, though, and go for an external one.

Once that's done, I'll recase this puppy and see how they sound.
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