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Old 12th March 2005, 07:51 AM   #1
BillyM is offline BillyM  United States
diyAudio Member
 
Join Date: Feb 2005
Location: East TN
Default SIv1 is up and running...

Thanks to all you great folks here, I was able to get the SI up and running in the new enclosure with the SLA this evening.

Eh, mods?

Panasonic FM 1500uf capacitor in stock location (fits NICE)
Power tapped in at the main cap on the bottom of the board
Power tapped in at the positive side of each bypass cap
Signal direct to inputs where the ribbon was.
Unused traces cut and grounded (and sent to their rooms)
SLA, mmmmmm

The speakers are 93dB/1w/m efficent Athena AS-F2's.
Frontend is kernel stremamed lossless to Adcom GDA-600 D/AC
SignalAudio.com cables all round

Bass roll-off? Uhm. There used to be one, but not anymore! Intro to Norah Jones - Cold Cold Heart is just as full in the bass-region as with my Parasound.

Needs: Bias resistors. ...needs to be quieted down ALOT! Similar settings on the front-end produce more sound than the Parasound. ...so I pretty much get 3-clicks on the volume adjustment with the SI.... If anyone has some correctly sized 16k and 20k resistors, maybe we can work out a trade for a Panasonic 1500uf cap? I have a few spares...

Pictures come tomorrow...

Woohoo!
--BillyM
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Old 12th March 2005, 12:13 PM   #2
diyAudio Member
 
Join Date: Dec 2002
Location: Houston
Default Re: SIv1 is up and running...

Quote:
Originally posted by BillyM
Thanks to all you great folks here, I was able to get the SI up and running in the new enclosure with the SLA this evening.

Eh, mods?

Panasonic FM 1500uf capacitor in stock location (fits NICE)
Power tapped in at the main cap on the bottom of the board
Power tapped in at the positive side of each bypass cap
Signal direct to inputs where the ribbon was.
Unused traces cut and grounded (and sent to their rooms)
SLA, mmmmmm

The speakers are 93dB/1w/m efficent Athena AS-F2's.
Frontend is kernel stremamed lossless to Adcom GDA-600 D/AC
SignalAudio.com cables all round

Bass roll-off? Uhm. There used to be one, but not anymore! Intro to Norah Jones - Cold Cold Heart is just as full in the bass-region as with my Parasound.

Needs: Bias resistors. ...needs to be quieted down ALOT! Similar settings on the front-end produce more sound than the Parasound. ...so I pretty much get 3-clicks on the volume adjustment with the SI.... If anyone has some correctly sized 16k and 20k resistors, maybe we can work out a trade for a Panasonic 1500uf cap? I have a few spares...

Pictures come tomorrow...

Woohoo!
--BillyM

Billy,
When you feel up to it, try swapping in a couple of either 1.0 or 2.2 ufd caps for C3 and C4. With the 36K feedback resistor a 1.0 ufd cap may be fine.
If you lower the feedback resistor to 20K go for the 2.2 ufd. The stripped down evaluation board uses 40K feedback resistors and a 1.0 ufd coupling cap.
The stock 0.33 ufd coupling caps are okay if the speakers do not go very low. The graphs show the circuit is down 3 - 4 dB at 40 Hz. It is down 9 dB at 20.
Good to see that you have yours going in the new box. My next one is slowly coming together, waiting on PCMall right now, maybe be waiting a long time.


George
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Old 13th March 2005, 06:08 PM   #3
BillyM is offline BillyM  United States
diyAudio Member
 
Join Date: Feb 2005
Location: East TN
Default Re: SIv1 is up and running...

Quote:
Originally posted by BillyM
Pictures come tomorrow...
This gives you an idea of exactly how tall the PannyFM 1500uf cap is. ...please divert your attention from the bling-ey connectors on the back, they were all I had on me...
Click the image to open in full size.

Overall shot of the little bugger.
Click the image to open in full size.

Here's a closeup of my project. (Yes, my soldering on the backside of the spkr-posts is crap, those suckers were hard to solder to!) Cap fits in there real nice, no? I wish I had gotten pictures of the bottom, because my power-routing is sexy... Direct to the positive side of the supply capacitor, and the positive side of the two SMD bypass caps.
Click the image to open in full size.

(Yes I still need to relocate the LED, just currently lazy since its pushing good music... I have been listening to all my live music for the last 24hrs straight. ...4.5ah battery will push 80db (c-weighted) for 18hrs+ (havent had it on for longer than that... Switch up, battery -> amp; switch down, battery -> automatic 1a charger.

Thanks for the suggestion George. ...I should have some larger-value smd capacitors on their way to me... just need to source up some resistors now... Going to toss a heatsink on the little guy as well as look into RF choke replacements. ...lots of room on the bottom of the board that needs some tinker'in.

--BillyM
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