Welcome to Mapletree Audio Design

The use of 6BQ5/EL84 output tubes in the Ear+ HD250 was popular with customers who appreciated the wide availability of the type. Like the HD250, the new HD Super II utilizes the EL84 with triode connection in cathode follower mode (as is the 12B4A in the Ear+ HD). The 12AX7/5751 drivers are configured in SRPP topology. The power supply is constructed on a separate chassis to obtain the lowest possible noise floor and to minimize heat buildup in the main amplifier chassis, thus increasing component life expectancy. Both units are a compact 5" wide. Appearance is distinctive with brushed aluminum and chrome trim. Wood side panels are not available as both chassis have ventilation holes along the sides. The two chassis can be stacked, positioned side by side or even located on different shelves. A 1 ft power interconnect cable is supplied; longer cables can be requested. Available with 240 VAC wiring at no extra cost..

Vacuum Tube Sound for the 21^st 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 Photos of the Month Andy Chu (Taiwan). Custom LR 1 for phono switching. WBT NewGen RCA connectors, Elma switches. Jan Erling Veiset (Norway). Dead Parrot - personal design of ultra low noise line preamp/power supply. EF86/6BL8. Construction by Mapletree Audio using HD Super II chassis configuration. For more details and enquiries about having one built for you contact Jan at jan.erling.veiset@veiset.net August News and Specials • VACUUM TUBE VALLEY magazine: complete set of issues 1 to 20. Excellent condition, stored in binder. Reduced to $200 USD plus shipping. • Branches newsletter Issue 6 is available for downloading. It reviews the evolution of the new Ear+ HD Super II. • New! Ear+ HD Super II. The use of 6BQ5/EL84 output tubes in the Ear+ HD250 was popular with customers who appreciated the wide availability of the type. Like the HD250, the new HD Super II utilizes the EL84 with triode connection in cathode follower mode (as is the 12B4A in the Ear+ HD). The 12AX7/5751 drivers are configured in SRPP topology. The power supply is constructed on a separate chassis to obtain the lowest possible noise floor and to minimize heat buildup in the main amplifier chassis, thus increasing component life expectancy. Both units are a compact 5" wide. Appearance is distinctive with brushed aluminum and chrome trim. Wood side panels are not available as both chassis have ventilation holes along the sides. The two chassis can be stacked, positioned side by side or even located on different shelves. A 1 ft power interconnect cable is supplied; longer cables can be requested. Available with 240 VAC wiring at no extra cost.. User's Manual with full specifications Passive preamp option ($50) provides three inputs and a passive output.

Mapletree Audio Design Product Overview
**Go to: Preamps • Headphone Amps • Power amps •** Other products 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. Side panels are available in stained oak or ebonized maple (see Ear+ HD photos below for examples).
Preamplifiers
*Line 2A SE Line Preamplifier* 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/fast diode hybrid rectification) included. More Information • Customer Comments
*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 Ultra 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 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
Power Amplifiers
Stealth Max Monobloc Power Amplifier - 50 W with KT88s running class AB₁ ultra-linear with fixed bias. Triode mode switch. Built on a stainless steel Dynaco Mk III chassis with Mullard topology driver circuitry (6SJ7 voltage amplifier and 6SN7GT long-tail phase inverter) and Dynaco spec output and power transformers. WIth premium passive components and a very stiff power supply, the sonics are effortless and open, espeicially noticable on high level transients. Available for 240 VAC ( $30 additional). Download the User's Manual for detailed information.
*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 12SC7 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
The "Thingy" crossover and multi-channel driver. 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.
New! Viper 4+ deluxe magic eye monitor and line router. Separate peak and average eye tubes for each channel with individual sensitivity controls. Internal voltage amplifier allows monitoring signals from line level sources, preamp outputs, or power amp outputs. Includes a 3-input, 3-output line router with selected input signal monitored. Router functions without power applied. Dimensions 12" x 8". With 1629 cathode ray indicator tubes priced at $750 ($700 with Russian 6E5C tubes). Available for 240 VAC at no extra cost! 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 or lloyd@mapletreeaudio.com.

Vacuum Tube Sound for the 21st Century

Click on tubes for more information!

Preamplifiers

Headphone Amplifiers

Other Products

Vacuum Tube Sound for the 21^st Century