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krell ksa5 klone

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  • My Krell:        

  • Got it cased.  Pretty standard.  I apologize for the power switch--I couldn't resist.  

  • I completed the full modification (output stage and front end) on both channels and listened to the amp briefly. The headphones were Grado GS1000 and Sennheiser HD595, the 8ohm speaker were B&W 60

Posted Images

Here is how far I got until the next Mouser shipment:

 

bZyB5WEh.jpg

 

All the transistors are the originals and there are a lot of them.  :)

Nice! I would be interested in seeing your progress if you are up to it :)

  • 2 weeks later...

I just got the PCB !

 

As soon as I have a little time left, I can start the soldering job.

 

If someone is interested, I have some board left ::)

 

WXUWoKn.jpg

I just got the PCB !

 

As soon as I have a little time left, I can start the soldering job.

 

If someone is interested, I have some board left ::)

Hello Guys,

 

Sorry, but all the left boards are gone... :-

  • Author

bombs away  (ok, this is a mess)

 

1000uf 35v ls=5 dia=13mm 871-B41041A7108M000 35
.1uf 100v ls=5mm 80-R82EC3100DQ70J 14
4.7uf 63v wima 505-MKS24.7/63/5 7
470pf 500v  ls 5.9mm 5982-15-500V470 4
39pf 500v ls 5.9mm 598-CD15ED390JO3F  2
220pf 500v ls 5.9mm  598-CD15FD221JO3F 2
  
mjf15030 863-mjf15030g 6
mjf15031 863-mjf15031g 4
heatsink amp board 532-531302B25 8
mpsa56  19
mpsa06  23
lsk389  2
relay 653-g5v-2-h1-dc24 2
op27 digikey 4
  
500 ohm pot 652-3299w-1-501lf 2
3 pin terminal 651-1729131 2
2 pin terminal 651-1729128 2
  
2 ohm 5 watt 71-cpf3-f-2 8
10 ohm 71-rn60d-f-10 16
25.5 ohm 71-rn60d25r5f 8
100 ohm 71-rn60d-f-100 4
221 ohm 71-rn60d-f-221 2
402 ohm 71-rn60d-f-402 4
475 ohm  71-rn60d-f-475 8
680 ohm 71-rn60d-f-680 8
825 ohm 71-rn60d-f-680 2
1k ohm 71-rn60d-f-1.0k 4
1.5 kohm 71-rn60d-f-1.5k 4
2.74k ohm 71-rn60d-f-2.74k 10
3.65k ohm 71-rn60d-f-3.65k 4
4.7k 71-rn60d4701f 1
6.19k ohm 71-rn60d-f-6.19k 2
8.2k ohm 71-RN60D-F-8.25K 2
33.2k 71-rn60d-f-33.2k 4
47.5k 71-RN60D-F-47.5K 2
  
1n914  4
1n4746a 78-1N4746A-TAP 1
1n4007 512-1n4007 1
1n5408 821-1n5408 4

Edited by kevin gilmore

4.7uF 63V WIMA = 6pcs

2 ohm (3W) = 71-cpf3-f-2

Edited by Inu

Changed. The file is open to all for edit, so if anyone finds more error, feel free to correct it. :)

Another alternativ for the 1000uF/35V, is the Nichicon UFG1V102MHM (Mouser: 647-UFG1V102MHM).

A little bigger, but it's OK to put on the board.

 

Here is a picture with the condensators fitted.

 

58AUi50.jpg

I got some parts in and it is almost ready.  :)

 

pSLsImGh.jpg

Very nice!

How closely are the transistors matched?

Just basic matching, nothing more than that.  Mostly because I didn't have enough to do any major testing and sorting. 

I used Panasonic FM's which pretty much the best you can buy at a sane price. 

Zettler 24V Relay

A2830-2C-24DS

http://www.bgmicro.com/REL1086.aspx

MPS8099 and 8599 (0.15)

http://www.bgmicro.com/TRNMPS8099.aspx

http://www.bgmicro.com/TRNMPS8599.aspx

 

 

It is hard to pairing MJEs…    :-[

 

MJE15030G(NPN)

Lot:AFA50

hfe = 78 78 80 83 96 97 98 104 104 105 107 109 111 114

 

MJE15031G(PNP)

Lot: AFB09

hfe = 228 234 238 241 242 252 253 257 260 262  

 

I have the same problem :-[

 

MJF15030 (Lot: SPC05) HFE= 143 - 156

MJF15031 (Lot: SPB24) HFE= 246 - 257

 

-- o --

Rodrigo

I am replacing these to 2SA1930 and 2SC5171.

Edited by Inu

someone over at a Chinese DIY site has a working KSA5 clone based on the schematic Kevin posted.

He used his own boards, replaced mpsa06/mpsa56 with BC546/BC556, and changed the cap values a bit.

He seems to like the sound (obviously.) Right now.. he is playing with different caps.

 

Here is the link.

I didn't fare any better with the output devices but this amp will be as close to stock as is possible. 

 

someone over at a Chinese DIY site has a working KSA5 clone based on the schematic Kevin posted.

He used his own boards, replaced mpsa06/mpsa56 with BC546/BC556, and changed the cap values a bit.

He seems to like the sound (obviously.) Right now.. he is playing with different caps.

 

Here is the link.

 

Most of that doesn't make any sense to me.  Rolling caps which look mostly vintage... why would anybody do that? 

I am replacing these to 2SA1930 and 2SC5171.

 

 

Many thanks for this info, Is it possible that Krell had used transistors with these large differences of HFE?

 

someone over at a Chinese DIY site has a working KSA5 clone based on the schematic Kevin posted.

He used his own boards, replaced mpsa06/mpsa56 with BC546/BC556, and changed the cap values a bit.

He seems to like the sound (obviously.) Right now.. he is playing with different caps.

 

Here is the link.

 

:kitty:

 

-- o --

Rodrigo

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