Mapletree SUGARMAPLE Black Buff User manual

Black Buff Amplifier
Users' Manual
Rev Oct. 22/16
Mapletree Audio Desi n
Al Freundorfer
R. R. 1, Seeley's Bay, Ontario, Canada, K0H 2N0
[phone]
www.mapletreeaudio.com
[email protected]
© Copyri ht Al Freundorfer 2016
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Introduction
The Black Buff is desi ned as a stand-alone tube-output-buffer for CD players, DAC or any line level
device. The result is an improved tonal quality, relaxed open musical detail and ima in , reduced
listener's fati ue and enhanced 3D effect of better recordin s.
The Mapletree Audio Desi n Black Buff Amplifier represents a hi h performance development of an
octal-based buffer amplifier that uses the 6SN7/5692 or 12SN7 and is based on the cathode follower
from the Mapletree Audio Line 2 and Ultra 4 pre-amplifiers. Premium components include metal film
resistors and polypropylene film capacitors.
Many people would like to have the tube sound in their home theater without buyin and buildin an
expensive all tube system. This can be solved by addin three Black Buffs to the outputs of a
DVD/Home Theater player to brin its performance up to a tube level quality. Placin one Black Buff
on the front channel, one on the rear channels and a final unit on the center channel and sub output
(three Black Buffs total), turns your DVD/Home Theater player into a respectable soundin 6 channel
tube output with excellent sound.
Input/Output Connections
There are a sin le pair of RCA input and output connections. The RCA jacks allow connection to a
line-level stereo source while maintainin the connection to the re ular amplification system. The input
impedance is 1 MΩ which is compatible with all source output circuits. The RCA output jacks are also
at the rear of the Black Buff and can handle loads as low as 5K ohms.
The standard IEC line cord is attached to the receptacle on the rear panel of the Black Buff power
supply. It is compatible with a 120 AC volts. A 0.25A/120 V fuse provides primary protection for the
power supply. It is located on the back of the power supply unit. Under normal conditions, it should not
be necessary to replace the fuse. If power fails to come on, you can check the fuse and replace with a
spare if necessary. If the fuse blows a second time, you should not try to operate the unit. Contact
Mapletree Audio Desi n for information re ardin servicin . The power switches are located on the
front panel and the LED pilot li ht indicates the power on.
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Black Buff
2
Fuse
Holder
120 VAC Power
Input
Power Indicator LED
Power Switch
Tube sound control
Min. Tube sound:
Full Counter-
Clockwise
Max. Tube sound:
Full Clockwise
When turnin the knob
allow the bias to settle,
approximately 3
seconds, before critical
listenin . Normally
after turnin the knob
the output would sound
quieter with volume
slowly increasin and
improvin in clarity.
Audio
Input
Audio
Output Heater Volta e Switch
(6.3 VDC down and 12.6VDC up)

Controls
The Tube sound level controls the amount of tube sound is added to the audio from input to output
when the selector switch is set to Black buff mode. When turnin the knob allow the bias to settle,
approximately 3 seconds, before critical listenin . Normally after turnin the knob the output would
sound quieter with volume slowly increasin and improvin in clarity.
Tubes
A tube burn-in period of several hours may be needed to achieve the best sonic performance. Tube life
should be thousands of hours. A in tubes may result in a reduced ain in one or both channels or an
increase in noise levels. Infrequently, a heater may burn out which is indicated by total loss of sound.
The Black Buff is supplied with 1 – 6SN7 or 12SN7 tube. Replacement tubes can be obtained from
several suppliers in the U. S. and Canada. 6SN7 types are currently manufactured and are also available
as new old stock (NOS). Some listeners enjoy tryin different brands and variants of tubes. The
reatest sonic variation will occur with different driver tubes.
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123

Warranty
Tubes are warranted for 90 days exclusive of shippin cost.
Additional Notes
This manual is an aid to the user for the operation of the Black Buff. Details of the amplifier and power supply circuits are
subject to chan e without notice so as to achieve the best possible performance. The schematic is only representative of the
actual amplifier and component manufactures, model and values may vary.
4
Back
6SN7 or 5692
Front

MAD Black Buff pecifications
Frequency response at 0.2 Vrms output into 4.5k, 10k and 25k Ohms load:
10 100 1000 10000 100000
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
Frequency [Hz]
Relative Gain [dB]
1Vrms output at 1 kHz: 10K Ohm load predominately 2nd order distortion.
Output impedance at 1 kHz: 454 Ω
Input impedance: 20 kΩ
Hum and noise at output: less than 0.1m Vrms
Phase: non-invertin
Power consumption: 4 W, 120 VAC (230 and 240 VAC) 50-60 Hz
5
V
out=1.0 Vrms
4.5K Ohm Load
10 K Ohm Load
25 K Ohm Load

MAD Black Buff Headphone Amplifier
Version: 4
© Copyri ht Al P Freundorfer 2016
Rev. Oct. 2016
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