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Post by Deleted on Aug 11, 2010 22:25:51 GMT
Yes.. automatically translated so it seems. they are mentioning to match the input FET's. might be a good idea to buy some input FET's and match them. connect the gate and source and measure the drain current (using 9 or 12V power supply) as shown in the webpage. match the FET's and use these matched pairs. Alex LOVES to match the input stages ! Hi Frans NOT with damn FETS! I used to do similar years ago with piles of 2N5484 for constant current source use. If you check a more recent post by the respected DIYAudio member Andrew T in the link I sent you, you will see that matching FETS properly is much harder than you are suggesting. Regards Alex |
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Post by PinkFloyd on Aug 11, 2010 22:45:45 GMT
Oh god...... here we go  |
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Post by Deleted on Aug 11, 2010 22:50:00 GMT
Though I have not ordered one of these kits, when I was looking at it and it's requirements I found these toroidals. To my limited knowledge they seemed decent value... |
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Post by PinkFloyd on Aug 11, 2010 22:52:01 GMT
............................... will probably sound just the same if you fit the FETS as they come A couple of years ago I went through a batch of 300 (or so) and "matched" them..... fekkin' waste of time, sounded the same to my old ears A £40 headphone amp kit with parts? Fit what comes in the box and enjoy the music.... the moment you start pishing about with matching transistors is the moment you have gone from enjoying the music to "examining the parts"...... |
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Post by Deleted on Aug 11, 2010 22:54:56 GMT
Oh god...... here we go Mike Just throw it together on a breadboard. If it sounds good, then put it in a decent case like you suggested.If it is only mediocre, then you haven't exactly lost much have you, as it was such a bargain. Alex |
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Post by PinkFloyd on Aug 11, 2010 22:57:05 GMT
Oh god...... here we go Mike Just throw it together on a breadboard. If it sounds good, then put it in a decent case like you suggested.If it is only mediocre, then you haven't exactly lost much have you, as it was such a bargain. Alex Exactly! |
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leo
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Team wtf is it?
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Post by leo on Aug 12, 2010 7:05:59 GMT
If the Fets are sited together on the pcb in pairs you can buy dual Fets in a single package which are matched (although tend to be expensive and hard to find) Matching by hand can take time, temp drift etc can be a PIA. Just build her as stock first, you can faff about later  Anyway, Its seems all those kits on ebay have now gone, Too slow  |
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Post by Deleted on Aug 12, 2010 7:54:40 GMT
> Mike Just throw it together on a breadboard. If it sounds good, then put it in a decent case like you suggested.If it is only mediocre, then you haven't exactly lost much have you, as it was such a bargain. Alex > I thought this site was all about modding and squeezing the most out of the gear ? Where is the adventurous mind ? You won't need a breadboard as it comes with a PCB. > ............................... will probably sound just the same if you fit the FETS as they come A couple of years ago I went through a batch of 300 (or so) and "matched" them..... fekkin' waste of time, sounded the same to my old ears I agree Mike.  Only tossed it in because they were talking about it on that site and to draw Alex out of his corner ... I am serious about adding output resistors though and perhaps an input filter. (have to honour Mike's description of me) |
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Post by Deleted on Aug 12, 2010 8:27:51 GMT
> Mike Just throw it together on a breadboard. If it sounds good, then put it in a decent case like you suggested.If it is only mediocre, then you haven't exactly lost much have you, as it was such a bargain. Alex > I thought this site was all about modding and squeezing the most out of the gear ? Where is the adventurous mind ? You won't need a breadboard as it comes with a PCB. > ............................... will probably sound just the same if you fit the FETS as they come A couple of years ago I went through a batch of 300 (or so) and "matched" them..... fekkin' waste of time, sounded the same to my old ears I agree Mike. Only tossed it in because they were talking about it on that site and to draw Alex out of his corner ... I am serious about adding output resistors though and perhaps an input filter. (have to honour Mike's description of me) Frans You are in danger of becoming a bigger s.h.i.t.stirrer than me me ! Mike has made it plain recently that he hasn't got the time to fart around too much. The breadboard idea was from Leo, and was meant to include the transformer sitting on it too. As for balancing,and "the sweet spot", confirming reports are now coming in from across the globe, so one day you may also have to consider the possibility that I may also be right about that identical check sum business too .   Alex |
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Post by Deleted on Aug 12, 2010 8:48:02 GMT
> You are in danger of becoming a bigger s.h.i.t. stirrer than me ! Sort of like a mini-me ? > confirming reports are now coming in from across the globe So are UFO reports ! LOL.. ;D Just kidding Alex.. I am in favor of matching input stages as you are. If it were only to make the DC offset/temperature behaviour on the output smaller and delete offset pots or the need of DC servo. Have to agree with Mike though, that if you can't hear the difference it is a waste of time. If you can hear it then in your case it's not a waste of time.  FET's are indeed a LOT harder to match exactly then bipolars. To do it right you would have to match the graphs over a voltage/current range just like the glowy bottles  . |
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Post by PinkFloyd on Aug 12, 2010 9:44:43 GMT
Anyway, Its seems all those kits on ebay have now gone, Too slow Says there are still three available? |
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Post by PinkFloyd on Aug 12, 2010 9:47:06 GMT
We were talking about mounting the PCB / PSU on a "chopping board"  |
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Post by PinkFloyd on Aug 12, 2010 9:52:52 GMT
Not so much don't have the time to "fart around" more a case of I don't "waste" time being anal about things.... I "could" spend DAYS sifting through a large batch of FETS in an attempt to match a few of them... I could also spend the time breathing some fresh air and getting some sun on my face I'll do as Leo suggests..... build up the kit, see how it goes and THEN "fart around" should it sound like turd  |
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Post by Deleted on Aug 12, 2010 12:51:05 GMT
Anyway, Its seems all those kits on ebay have now gone, Too slow Says there are still three available? There all gone Mike, says this at the very top left side of page, hope they make some more available, will try to have a go myself, with your and others guidance of course. |
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Post by Deleted on Aug 19, 2010 20:08:43 GMT
If anybody is interested!! I have been in touch with davidlouis1983 the seller of this kit, and it appears that he has some more kits which he may make available, he has asked me how many i want, just the one please, but it might be worth pushing the "ask the seller a question" button if you also would like one of these kits. Mick. |
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Post by PinkFloyd on Aug 19, 2010 20:49:23 GMT
By the way......
My kit arrived on Monday (superfast shipping from Hong Kong!)
I had a quick look at the board / parts this afternoon and it is all SUPERB quality "genuine" stuff.... the PCB is "luxurious" quality, the ALPS pot is genuine.... I took it apart and it's 100% genuine with 8 wipers (fakes tend to have 3 wipers).... the capacitors are high quality, genuine "for audio" ELNA types.... it ALL, IMO, suggests this is the real deal.... I will take close up photos of the parts when I have time.
If you "can" still buy these then don't hesitate, it's all top quality stuff.
Pics to follow.
Mike.
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Post by clausdk on Aug 19, 2010 20:54:43 GMT
Glad to see your are in on this too Mick, then we will se some spetacular metalwork for knobs and other bits and bobs.. I have already started designing the casework, I think it will be another one for hanging on the wall, but still quite different from my Chiara-box.. I must admit that the wood/casework is what I really look forward to, all the soldering is a bit boring If anybody is interested I will provide boxes at cost price. |
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Post by Deleted on Aug 20, 2010 14:24:21 GMT
My Amp is on its way, "davidlouis1983" has informed me that he will be listing some more on September 8th , seems a very pleasant straight guy to deal with. Mick. |
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Post by clausdk on Aug 21, 2010 12:08:30 GMT
My kit arrived today, boxed like crownjuwels, but not much help..
Looks like good stuff, not that I know anything about that..
But boy am I in deep water here, I am quite sure that I can get the pot mounted, also some of the caps seems possible, the longer leg is + right ??
The black caps has the same length on the legs, how do I know which is + ??
I have about a million questions more, but need to do this slowly, very slowly
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Post by clausdk on Aug 21, 2010 21:05:54 GMT
mounted, also some of the caps seems possible, the longer leg is + right ?? The black caps has the same length on the legs, how do I know which is + ?? I suspect that the row of zeros marks the -, at least it looks like that on the pictures.. Another thing I got four blue resistors, the ones right beside the big caps, the board says 2,2, but they messure 3,0 would that be a problem ??, it is the only resistors I got left and they do not fit anywhere else HELP I also got a 10 Uuf cap that does not seem to fit anywhere and I got a 100 uf spot for which I have no cap ?? I have fittet everything exept the small black 3 legged fellows (transistors IIRC) and the trimpots, there are two types the board says "C1815" but those I got say "H501I next line says p0915" and the other type says "W201I next line P0306" Also the diodes have not been fitted yet, but they seem pretty straigth forward  Last I have a 8 legged bar that says "FC1237, next line says YOC1HB" at the end of the row of legs the board has a "square" marking for one leg, how do I find out which way to turn it ?? It has been a loooong evening and I have messured every resistor to be sure.. An other thing that puzzels me is that I have got two type of "dale" resistors that both messure 1500 ohm, how does one know which to use where ?? |
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Post by PinkFloyd on Aug 22, 2010 20:52:32 GMT
My kit arrived today, boxed like crownjuwels, but not much help.. Looks like good stuff, not that I know anything about that.. But boy am I in deep water here, I am quite sure that I can get the pot mounted, also some of the caps seems possible, the longer leg is + right ?? The black caps has the same length on the legs, how do I know which is + ?? I have about a million questions more, but need to do this slowly, very slowly Hi Claus, Don't do anything yet. I will start a comprehensive step by step "build" thread (with photos) next week. I still haven't got into "build mode" but will force myself The + (positive) side of an electrolytic capacitor usually has a longer leg then the - (minus). The negative side will always have a "band" running down the side of the capacitor which also denotes the negative (-) side. Non polar electrolytics will not have a band running down the side.... they can be fitted any way round.... so the green MUSE (BP) caps can be fitted any way round..... "BP" stands for "Bi-Polar" which is the same as non polar. Don't worry man, we will build this amp step by step.... slowly but surely.... I will guide you through the process in a painting by numbers / easy to understand way.... just give me a few days to get it started. Mike. |
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Post by PinkFloyd on Aug 22, 2010 20:57:19 GMT
mounted, also some of the caps seems possible, the longer leg is + right ?? The black caps has the same length on the legs, how do I know which is + ?? I suspect that the row of zeros marks the -, at least it looks like that on the pictures.. Another thing I got four blue resistors, the ones right beside the big caps, the board says 2,2, but they messure 3,0 would that be a problem ??, it is the only resistors I got left and they do not fit anywhere else HELP I also got a 10 Uuf cap that does not seem to fit anywhere and I got a 100 uf spot for which I have no cap ?? I have fittet everything exept the small black 3 legged fellows (transistors IIRC) and the trimpots, there are two types the board says "C1815" but those I got say "H501I next line says p0915" and the other type says "W201I next line P0306" Also the diodes have not been fitted yet, but they seem pretty straigth forward Last I have a 8 legged bar that says "FC1237, next line says YOC1HB" at the end of the row of legs the board has a "square" marking for one leg, how do I find out which way to turn it ?? It has been a loooong evening and I have messured every resistor to be sure.. An other thing that puzzels me is that I have got two type of "dale" resistors that both messure 1500 ohm, how does one know which to use where ?? I didn't read the above.... erm, slow down Claus Let's sit back, look at the contents of the kit, peruse the schematic, have a think about it and THEN start putting it together when we know what we are doing..... this is usually the most prudent way to go about things |
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Post by Deleted on Aug 22, 2010 21:05:34 GMT
Don`t worry claus, I will be in exactly the same boat as you building this and i have not even seen the parts yet  should be fun though ;D just going to check my house insurance to make sure i have adequate cover for when i switch it on for the first, and possibly the last time Mick. |
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Post by PinkFloyd on Aug 22, 2010 21:15:45 GMT
Don`t worry claus, I will be in exactly the same boat as you building this and i have not even seen the parts yet should be fun though ;D just going to check my house insurance to make sure i have adequate cover for when i switch it on for the first, and possibly the last time Mick. Mick...... We will take it slow and start off by populating the resistors..... follow the guide and you will have an amp that fires up "first" time (assuming your soldering skills are good). Mike. |
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Post by clausdk on Aug 22, 2010 21:30:14 GMT
I didn't read the above.... erm, slow down Claus Let's sit back, look at the contents of the kit, peruse the schematic, have a think about it and THEN start putting it together when we know what we are doing..... this is usually the most prudent way to go about things I know that is the right way to do things, but I can not read scematics and the contents of the kit, does not really tell me much. So I just painted by numbers and it all fitted exept for the things i mentioned and being unable to read the scematics I am pretty much helpless, when the numbers and the paint do not match.. But I will be patient and wait for my master to show his skills  I just hoped somebody could throw me a bone and I could be the first to finish the amp |
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should be fun though ;D just going to check my house insurance to make sure i have adequate cover for when i switch it on for the first, and possibly the last time 