Krell Krell clone Schematic

1		2		3		4

A

	B
					Main PCB
		+V
	C		R103	R112	R116
		C110	47K
				1K5	1K5
		10uF
		16V

R108

+1K5

							Q101			Q103
				D109	R104		2SC2240			2SC2240
			GND		4K7
						ZD101	R110	R114		R118
D							9K1	100R		100R
					R131
				R105	22K	GND
Input	R101			5K
	1K
										GND
		R102		C101
		22K
				680pF
							R111	R115		R119
E	GND	GND	GND				9K1	100R		100R
									R129
					R106				1K5
				D110	4K7		Q102			Q104
							2SA970			2SA970
									+ C102
				+		ZD102	R109	C104	1000uF
									16V
							1K5	100nF
									C103
				C111
									+ 1000uF
			GND	10uF	R107		R113			R117
				16V	47K				16V
							1K5			1K5
						GND

GND

F

-V

GNotes!

Components designated 1xx are placed on main PCB

Components designated 2xx are placed on heatsink or speaker binding posts Components designated 3xx are additional output protection circuits

All capacitors 100V exept where designated otherwise Q111 must be placed on main heatsink

Q109 and Q110 must be fitted with suitable heatsink

V-I Limiter: 1: (RVI 1 / RVI 2 / RVI 3) = app. 100R for safe SOA

H

R120

3K39

C105

330pF

Q105

MPSA92

Q106	Normal/Low BIAS
MPSA42
R144
5K
C106
330pF
R121
3K39

5		6		7		8		9		10		11

Output Board

		R130									+V
		22K
								RB 3
										D201
								2R2	Q3
										OPTIONAL
									MJL21194
							RB 2
							2R2	Q2
R122								MJL21194
101R						RB 1
						2R2	Q1
	C107			P. Output	Base		MJL21194
	100pF
		Q109
Q107						RVI 1
		MJE15032
MJE15033							RVI 2
	D301
								RVI 3
				P.V-I	V-I
C	Q301	Positive	V-I limiter				RE 1	RE 2	RE 3
R124 Q111	MPSA42						0R5	0R5	0R5	OPTIONAL
??? 2SC3955		C301
										Could be placed on speaker binding posts
	D303	22uF	+
B								Output
R125		R127		R301						L201
	D304
820R		25R
				100R						5uH
	C109
E
	100nF
				Feedback
	D305	R128		R302						R206	Output
		25R	+	100R				Output		4R7
	D306	C302								R205
										10R
		22uF
	Q302
							RE 1	RE 2	RE 3
R126	MPSA92									C201
		Negative V-I limiter					0R5	0R5	0R5
5K										100nF
	D302			N.V-I	V-I			RVI 3
Q108		Q110					RVI 2
						RVI 1					GND
MJE15032		MJE15033
	C108						Q1
	100pF
				N. Output	Base	RB 1	MJL21193
R123						2R2
101R								Q2
							RB 2	MJL21193
							2R2
									Q3
								RB 3	MJL21193	D202
										OPTIONAL
								2R2

-V

Output Board

Fitted on main heatsink

Copyright

DELTA AUDIO DENMARK

File Name

Krell-Clone KSA-50.sch

www.delta-audio.com

Date 17.10.2004

Date 21.10.2004

Date 21.10.2004

Date13.02.2005

Rev.

1.1

Rev.

1.2

Rev.

1.3

Rev.

1.5

Project

Krell-Clone KSA-50

Dept.

Drawn by

Checked

Released

R&D

JD

Circuit Name

Krell KSA-50 Clone

Size

Code

Status

Sheet

A3

UR

IP

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