Vacuum
Tube Sound for the 21st Century
Mapletree Audio
Design offers
a unique range of products designed and hand crafted by Dr. Lloyd
Peppard,
a retired electronics engineering professor. The goal is to increase
your
enjoyment of recorded music through the use of vacuum tube
amplification
and signal processing. 
Click on tubes for more information!
Customer photo of the month
Andreas Pedersen, Bodø , Norway. SR70 Special Red driver board in a customized Dynaco ST 70 power amp. Note the use of 5693 special red versions of the 6SJ7. "The sound? Like crystal clear water... giving life to subtle information in the music, which use to be invisible to the [previous replacement board], and also bringing back the joy of hi-fi!! During the last month I've been listening to just as much music as I've been doing all year! Would I ever consider selling it?!! Not over my dead body!!
So, thanks for an exellent upgrade!!"
January News and Specials
• Price reductions on popular Mapletree products! Yhe contonued strength of the U.S. dollar permits continued price reductions on the following components:
• Line 2A SE line preamp with PS 2 power supply $820 $740 USD
• Ultra 4A SE phono/line preamp with PS 2 power supply $980 $880 USD
• Ear+ HD headphone amp $740 $680 USD
• Ear+ HD Super $850 $800 USD
• 2 inputs, 1 output
• 2 x 12SN7GT NOS or can be wired for 6SN7GT without tubes (–$20)
• Panasonic polypropylene film signal capacitors/precision metal film resistors throughout
• 6" x 10" footprint
• 12 dB gain
• 240 VAC version at no extra cost
• Line 2 Integra. An upgraded version of the new Line 2A LE with Auricap signal capacitors, Alps volume control, maple end panels/standard chassis colors. $750 $700
Please enquire for more details.
Download the User's Manual for detailed information.
NOTE: All MAD components, with the exception of the Super Stealth and Stealth Max power amplifiers, are available for 230-240 VAC 50 Hz at no extra cost. Super Stealth and Stealth Max monoblocs for 230-240 VAC are available at a slightly higher price.
Chassis colors include RCA red, textured
black, Sylvania yellow, eggshell white, cobalt blue, and sage green. Solid maple side panels are
finished in ebonized black or natural.
Preamplifiers
Line 2A SE Line Preamplifier (kit and assmebled)
Review
of Line 2A SE by John
Hoffman in Affordable Audio
July/07 issue
Review
of Line 2 by Chris Thompson on Head-Fi
• Line 2A SE Preamp wins "Affordable$$Audio 2007 Big Bang, Little Bucks Award". See the January Issue of Affordable$$Audio (www.affordableaudio.org).
• Premium
passive
components include Auricap coupling capacitors.
• Optimized circuitry for lowest distortion
and
noise.
• 3 inputs, 2 outputs, volume and
individual
channel level controls.
• 2 x 12SN7GT with switch for 6SN7GT tubes.
• Separate PS 2 power supply (with
6X5GT
tube/HEXFRED hybrid rectification) included.
More
Information • Customer
Comments
Phono 4 SE Phono Preamplifier
Offered for those desiring a phono preamp without the line input and
control features of the Ultra 4A SE (see below). Front panel
gain
control with up to 50 dB gain. Can feed a power amp directly or
recorder/computer
input (for CD-R) or can be combined with a line preamp for additional
gain.
Two switchable inputs (rear panel) can have different load resistance
and
capacitance if desired. The circuit is identical to the Ultra 4A SE
with Auricap capacitors used throughout. Also includes a heater voltage switch for use of either 6SN7GT or 12SN7GT tubes in the
output
stages. Includes the separate PS 2 power supply.
Customer feedback
• More information
Ultra 4A SE Phono/Line Preamplifier
"MAD [Ultra 4] is my vote for best bang for the buck, heck maybe even best product contention at any reasonable price".
NEW! Customer
Review
of Ultra 4A and Ear+ Purist
Reviewof
Ultra
4A by Pat McDemott on Audio
Asylum
Review
of
Ultea 4A SE by JR Cody on audioweb.com
Reviewof
Ultra 4A by Scott Faller (TNT-Audio)
Reviewof
the Ultra 4 by Tom Mitchell on AudioCircle
• Premium passive components include Auricap
coupling
capacitors and Black Gate bypass capacitors. • 48 dB phono gain, two 18 dB line inputs, two line outputs.
• Individual channel level controls plus volume control for optimum gain adjustment.
• 2 x 12SN7GT (switchable for 6SN7GT) and 2 x 12SC7.
• Separate PS 2 power supply included.
(Shown in custom grey hammertone finish)
More Information • Customer Comments
PS 2 Power Supply (included with Line 2A SE (kit and assembled), Phono 4 SE, and Ultra 4A SE)
• Provides 12 VDC@1A (regulated)
and +200
VDC@15 mA.
• Power cable and
detachable
IEC line cord included.
• Employs high-speed diodes with 6X5GT rectifier
tube in hybrid bridge.
• Soft startup relieves stress on
tubes
and filter capacitors.
More
information
Headphone Amplifiers
"Now I have to listen to all my CDs all over again. I have a decent stereo system but with the Ear+ it sounds like a $20,000 setup".
Review
of the Ear+ by Steve Albers on Audio
Asylum
Review
of the Ear+ by Nicholas Schell on Head-Fi
Comments
on Audiogon
Designing
the Ear+ by Lloyd Peppard
User
Comments
Ear+ HD High Definition Headphone Amplifier (kit and assembled)
• Outstanding headphone performance for a wide range of headphone impedances and drive requirements.
• 2 x 12B4A NOS and 1 x 5751/12AX7/ECC83 tubes.
• High and low impedance headhone jacks.
• Premium passive components include Tantalum film plate resistors and Black Gate capacitors in signal path.
• Ultra high-speed rectifier diodes and Alps volume control are standard.
• Passive line output for use as a passive preamp.
• Dual inputs for easy patching into system.
More Information • Customer Comments
Ear+ HD Super Headphone Amplifier (assembled only)
Based on experience with the high-voltage power supply of the HD200 Special Edition, the new HD Super offers increased power output plus the benefits of soft-start tube rectification. It will drive two or more sets of headphones simultaneously. Other specs and features are the same as the Ear+ HD including dual inputs and passive output. A Black Gate filter capacitor for the driver stage plate supply is standard. Options include an all-Black Gate power supply ($60), locking Neutrik headphones jacks ($30), and a DACT stepped attenuator ($230). Chassis is 12" x 8" with rock maple side panels.
Super Stealth monobloc
power amplifier
(kit and assembled). Using the new EH 6V6GT tubes in class AB
ultra-linear
push-pull, the Super Stealth delivers a clean 8 W, making it
suitable
for a wide range of speaker systems. Available as a kit or factory
assembled.
•
20-20
kHz -1 dB at 5W
• Mullard topology driver circuitry using 12SJ7 pentode and 12S
C7
cathode-coupled
phase inverter.
• Supplied with EH 6V6GT matched pair output tubes.
• Quiet, ultra high speed diode power supply and DC heater
supply for all tubes.
• Ultra-low output noise–less than 025 mV (90 dB below rated output)
makes it suitable for high-efficiency speaker systems.
• Input level control for optimum sensitivity adjustment; input
sensitivity 0.5 V.
• Compact chassis 7" x 12" x 6" overall.
More Information
Super Stealth kit manual
Special Red octal driver module for Dynaco Stereo 70 power amplifiers. A drop in, point-to-pointwired driver board using Mullard driver topology with 2-6SJ7 and 2-6SL7GT tubes.
More Information
Installation Manual
Other Products
Based on the concepts described in the Branches newsletter issue 4 , the MAD Thingy is in production. It features buffered high and low pass filters to implement a 500 Hz high-level crossover for driving multiple speaker systems or bi-amp aplications, plus outputs for ambience and subwoofer channels. For more details, you can download the user's manual.
User comments.
Eyes for your Ears! The Viper Magic Eye Monitor. Left and right channel levels are displayed by two 6E5C cathode ray tubes. Includes response speed and sensitivity controls with built in 12SC7 voltage amplifier stage.
More information.
Download the User's Manual for detailed information.
LR 1 Line Router
• Any combination of 6 or less I/O lines is possible. Design it yourself to suit your needs.
• Ideal for switching line sources between headphone amplifier or preamp or adding additional line inputs to preamp.
• LR 1 Pro model features 3–2 switching with balanced I/O and XLR connectors.
Dr.
P spins some 78s on his mini system. Photo by Christian Keresztes
For more information or to place an order, please telephone or email Lloyd Peppard at
(613) 387-3830
info@mapletreeaudio.com
Lloyd Peppard
Mapletree Audio Design
158 Seabrooke Rd
R.R. 1, Seeley's Bay, Ontario, Canada K0H
2N0
Credit
card payments through PayPal are highly recommended. Registered PayPal
email address is lloyd.peppard@sympatico.ca.