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Old 21st August 2006, 07:28 AM   #11
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I dont know which version. They are cylindrical shape with two sticks on the bottom.

http://cgi.ebay.com/Solen-2-2uF-400V...QQcmdZViewItem

^^ would that be good?
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Old 21st August 2006, 08:24 AM   #12
Pano is offline Pano  United States
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Yes, the Solen caps are a very good choice. The Jantzen caps at Parts Express also sound nice.

As for the sound of the SI, I'm with you, sort of.
As the amp comes stock, I don't like it much. No bass, harsh highs. Does have a ton of detail, though. I can't understand why it ever got such good reviews. But it did, and here we are.

Once modified, the SI can really change. The two most important modifications are the removal and replacement of the input caps and C10. Both these can really change the sound for the better. A good PSU would be the next step. All of this has been covered in other treads over the past year or more.

If you really want a taste of what the Tripath chips can do, try an AMP6, Charlize or Autocostruire amps.

For these low power amps, you really need efficient speakers. 92dB/W minimum for good volume. You should be pushing 100dB/W or better for real "Live" levels. The same would apply for low power tube amps, or even solid state.
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Old 21st August 2006, 04:22 PM   #13
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which Capacitor from Partsexpress would be good for the C10 mod? Any links on how to do it?
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Old 21st August 2006, 05:01 PM   #14
Davet is offline Davet  United States
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The capacitor which will fit directly into the place of the existing C10 is a 680 MFD which may be purchased from:

http://www.Digikey.com

The 680 MFD 16 volt capacitor Digikey part number is P12378-ND at a cost of $0.43 (US) each. The Panasonic part number is EEU-FM1A681L.

A slightly larger (larger diameter) 1,000 MFD capacitor part is P12366 at a cost of $0.59. The Panasonic part number is EEU-FMC102.

Personally, I have used a 1000 MFD in place of C10 with two additional 1000 MFD caps connected in parallel to C10 from below the board. This provides me with 3,000 MFD for C10. The original cap is a 330 MFD. I have no problem driving my speakers with this setup using a variable 3 ampere power supply set at 13.1 volts.

You may also want to purchase some polypropylene film caps from Digi-Key. You could use smaller values 2.2, 3.0 etc. caps to replace your Solens. You may be able to reduce some of the turn on thump.
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Old 21st August 2006, 09:39 PM   #15
Pano is offline Pano  United States
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Follow Davet's lead on the C10 caps.

For input caps, you can use as small as 1uF with good results and less turn on thump.
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Old 24th August 2006, 04:36 PM   #16
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Default Re: No lows?

Quote:
Originally posted by sx881663
You have not done your homework! The stock SI has very limited bass. The input caps must be changed for larger/better ones and an adequate power supply must be used. This is for starters, the next thing is that the SI does not like speakers that have complex crossovers and are inefficient. They are just too power limited to handle this situation. Now take the situation like my friend, he uses the little SI to drive his really big old Altec speakers and it fills a large room with very good sound. He has dozens of amps all the way up to an industrial pro sound unit of 600W/ch. Most all are modified and good sounding but he prefers the SI.
These little things are capable of astounding sonics but only modified and with the right speakers!
Roger
I've been reading up a little on modding them, but I am reading a lot of acronyms that I do not yet understand. Am I missing a link to a already asked a million times link, or does anyone have pictures of the mods.

I am truly in love with the SI, but it does need more bass. I have hooked them up to my Infinity SM115s that are rated at 100db sensitivity and the mids and highs are absolutly crazy. The play back device used in testing is a cheap sony SACD player SCDCE595. Another best bang buck item if anyone wants a SACD player. I got it for $125 on Circit City's outlet price. They no longer support SACD at all. The retail price is around $150+.

Anyway, aside from being bass shy, I still can't stop listening to this thing. I've been playing everything from rock to jazz. Last night I threw in one of my all time favorite CD (being one of the best sounding for some reason IMO) Eric Claptons Unplugged. After I bought my HT equipment in the late 90s, I knew that my speakers were loud and a little bright, but I was young and I liked to JAM, and I made a compramise between loud and realistic sounding(I thought they sounded better then klipsch). I went back to go buy a pair of paradigms later (one of my favorite music speakers I've heard in my price range), but my tax refund was more then short that year, so I didn't get them. Anyway, to try and get to the point, I took my Eric Clapton CD with me to listen to the paradigm speakers. I acually listened to the ones I wanted to buy, and ones that cost well over $1000, but they were hooked up to seperates and of corse I heard things in the background that I have never heard before. Mainly the backup interments and vocals and all the things that you don't even know are on a CD. Well, I am hearing all the hidden sounds in CDs and SACDs that I have never heard before comming from the SI.

If more bass can truly be had from modding the SI, then I have would have to agree with 6moons.com review on the little amp. As it is in stock form, even after being burned in, it's still just too weak on the bass. I don't see how it could be compared to a $800 amp or even higher priced items while missing the bass. I put in Hurbie Hancoks rocket and while I could hear bass hits, they seemed to go away just as soon as they arived. Also, not quite low enough either.

I plugged my Yamaha 5.1 amp back in and listened to some of the same music, and it had more bass and I got the typical sound that I would want for movie play back, but all the clear notes and detail were gone. Sure it still sounded good, but the SI can create sounds that regular amps just can't come close too.

Let the modding start. I need more cowbell, uh er, I mean bass.
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Old 24th August 2006, 06:33 PM   #17
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Default SI or not to SI that is the question

You have not given us any information about yourself. Do you understand and work with circuits? Can you solder fine parts into a circuit competently? Are you planning to recase the unit with upgraded parts?
Real quick, the time, effort and money make it nonviable. A better choice would be a 41HZ or Charlie type kit. For the best in low power acquire 2 of Brianís D10.1 amp kits. For more power the choices open up with UcD, cold power, newclassd, larger Tripath etc.
Give us more as to what you want to do,
Roger
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Old 24th August 2006, 08:35 PM   #18
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I am new to circuits, but I understand the basics. I am (at this time) only interested in replacing the capacitors as Davet suggested. I do belive I have soldered enough to replace a few caps. I am not at the level of engineering anything yet, or fully understanding as to why to use one cap over another. I can only follow direction of what someone else has already done.

The I got t-amps to power speakers in my gym and bedroom. Even with all the hype and personal reviews from Amazon.com and other places, almost everyone was happy with what it could do, I just had to give them a try. For the price with power supply's, it was worth a shot. At any rate, it sounded like they could play music, and that was all I really needed them to do, only the hype and insaine reviews are not so rediculas, so I do want to improve my t-amp for a small price.

My background: I am a burnt out computer guy and I want to go back to school for a electrical engineering technology degree. Out of all the things I love in this life, music is on the top of the list. I need the education so I can build better stereo stuff at DIY prices, and I need the degree to make more money. Any electrical background stuff I learned was more car related, but I have found and repaired shorts, wired and soldered stereo stuff, wire upgrades, ect, and I was tought as a kid how to solder, but I am a little rusty. I know people who can give me some refresher lessions. My father n law has a EET degree. Also, I probably wouldn't be so worried about working with a cheap amp. I let someone else replace caps in things when they cost about $250 or more to get used car ECU. I wasn't up for the task of socketing a duel layer board for a new ECU chip. Mainly because used ones are hard to find and a factory replacement is around $1,200. I wouldn't be so afraid to work on something that cost me $29.99. We spend that much in a weekend buying beer for a house party, and even then, we are only renting it.

So to answer your question, I am a newb, but I can solder, I know what a cap is, but I was hoping for something with pictures. Or maybe a hand writen diagram. I havn't even taken my t amp apart yet. I have only had them for about 4-5 days.

Later, I do want to get at least one better t amp (build a better living room stereo with better speakers), but at the moment, I just want more bass out of the units I have. Mainly because I like sneeking the thing back to the HT room and hooking them up to my loud speakers. Another goal is to use one of them in my computer room, but I am all out of speakers. I have the LSD book and I have read that mostly from cover to cover and getting a basic grasp of everything (I need to read it again), so along with learning how to build speakers, I am very interested in what these little chips can do. I've read up on them a little, but I havn't studied them to dealth or anything. I don't fully understand how they work yet.

My overall dream goals are to build good living room speakers to work with a T amp hooked up to a SACD player. My first attempt would probably then be moved to the computer room. In the end, I would need one really good t amp, and two sets of speakers. Maybe three. My gym speakers are barly effecent enough for the t-amp. All the speakers wouldn't need to be built at the same level as I use a MP3 player in the gym, and only a CD player in the bedroom. A computer room setup would be for game systems, and maybe computer output.

I have no desire to try and redo my whole HT or anything as I am happy with what I have. At least untill it breaks or becomes totally dated. Maybe years down the road, I might just be crazy enough to try and use t amp technology to power a HT, but that is not in my goals or plans right now. I'm trying to keep things realistic, and affordable. My father n law has built speakers before, so he should be able to get me off the ground. As for effecent drivers and a starter project, I've been eye balling the TANG BAND 25-1166S 1" NEODYMIUM TWEETER rated at 4ohms, SPL: 93 dB 2.83V/1m and the DAYTON DC130BS-4 5-1/4" CLASSIC SHIELDED WOOFER 4 OHM, SPL: 91.8 dB 2.83V/1m.
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Old 24th August 2006, 09:05 PM   #19
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Default SI information

http://www.diyaudio.com/forums/showt...230#post567230

This thread has a rather large amount of information in it as well as various links to pictures, parts, etc. Please spend some time with it and see if it answers your questions.
Roger
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Old 24th August 2006, 11:54 PM   #20
preiter is offline preiter  United States
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Default Re: Re: No lows?

Quote:
Originally posted by gvr4ever

I've been reading up a little on modding them, but I am reading a lot of acronyms that I do not yet understand. Am I missing a link to a already asked a million times link, or does anyone have pictures of the mods.
The answer is in this very thread :P

http://www.michael.mardis.com/sonic/start.html
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