background image

 

  

10K

Mapletree Audio Design Stealth Max Monobloc Power Amplifier

240 VAC for Murray Smith

Po wer

3A.

100/400

330K 1 W

100/400

+

V3

KT88

V4

KT88

Re v. July 12/08

10K

3

4

5

8

3

4

5

8

© Co pyright Ll oyd Peppard 2008

KT88s

1K

1K

1.5 H  20 0  mA

55 Ohms

6SJ7

6SN7

1

5

1

5

2

7

2

7

2

7

8

7

560

470/100

15K

50K

+

MUR180

Bi as

Bi as

CC W

+

+

100/400

ground bus

 Input

5VAC/3 A

400

0

400

V5

GZ34/5AR4

6.3 VAC  6 A

200 mA

2

8

4

6

Y

Y

GR

GR

GR/Y

60

R

R/BK

R/Y

R

BR

BR

chassis

10

Bias set

150K

150K 100/400

+

+

150K

150K

100/400

+498 V

3.57K

117

0.047/400

511K 100K

20K
2 W

0.1/4 00

0.1/4 00

221K

V1

6SJ7/6SJ7GT

V2

6SN7GT

3

5

6

22K
2 W

1

4

2

1

4

5

3

8

6

150p

10K

10K

2.7K

270 p

100K

221K

Level

T

UL

UL

T

A43 1S

4300  

C3 54

+437 V

+437  V

+163  V

+163  V

+97 V

+

P78 2Sexp

al l 1 W

100/400

+

100/400

+

150K

150K

5.1K 2W

16

8

4

+498 V

1M

11K
2 W

+107 V

1/400

511K

+69 V

+3.1 V

+348  V

-54 V

1.1 V

+495 V

+493  V

60 mA

+507 V

-72 V

-54 V

500

240 VAC

B

G

G/W

B/W

R

332 V

470/100

+

OR

Y

BR

BK

Summary of Contents for Stealth Max

Page 1: ...loc Power Amplifier Users Manual Rev July 16 08 Mapletree Audio Design Lloyd Peppard R R 1 Seeley s Bay Ontario Canada K0H 2N0 613 387 3830 info mapletreeaudio com http www mapletreeaudio com Copyrigh...

Page 2: ...A431S used in the original Mk III amplifier The power transformer is conservatively rated and can deliver the current required for maximum power output Soft startup is assured through use of a 5AR4 GZ...

Page 3: ...hed pairs as indicated on the boxes supplied with your amplifier Matched quads are not required as individual bias controls are used for each channel With the tubes installed connect the IEC power cor...

Page 4: ...g conditions the meter reading should rise to around 1 Volt Adjust the bias potentiometer using a blade screwdriver counterclockwise CCW if the voltage is greater than 1 1 V and clockwise CW if the vo...

Page 5: ...SJ7GT can be substituted without change in performance The special red series 5693 can also be directly substituted and offers the potential for very long life 10 000 hrs No currently manufactured ver...

Page 6: ...ply ac Rated power output 4 8 50 W Frequency response at 1 W output 15 Hz 44 kHz 1 dB Frequency response at 50 W output 20 Hz 20 kHz 1 dB Gain 24 dB 16 V V or 1 2 V input for 50 W output Input resista...

Page 7: ...V5 GZ34 5AR4 6 3 VAC 6 A 200 mA 2 8 4 6 Y Y GR GR GR Y 60 R R BK R Y R BR BR chassis 10 Bias set 150K 150K 100 400 150K 150K 100 400 498 V 3 57K 117 0 047 400 511K 100K 20K 2 W 0 1 400 0 1 400 221K V...

Reviews: