Related Manuals for Mapletree Stealth Max
Summary of Contents for Mapletree Stealth Max
- Page 1 Stealth Max Monobloc 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 © Copyright Lloyd Peppard 8...
- Page 2 Soft startup is assured through use of a 5AR4/GZ34 rectifier tube. ♦ A driver module based on the Mapletree Special Red SR-70 board for the Dynaco ST- 70. It employs octal tubes in a Mullard-type circuit with 6SJ7 pentode voltage amplifier and a 6SN7 long-tail phase inverter.
- Page 3 Powering up _____ Please read this instruction manual thoroughly before powering up your Stealth Max for the first time. The location of the tubes on the driver board and chassis are shown below. When installing tubes, locate the key on the central spigot and make sure it matches with the indent on the tube socket.
- Page 4 Biasing the output tubes________ The Stealth Max is designed to run the KT88 output tubes at a cathode (combined plate and screen grid) current of 110 mA per push-pull pair. With a plate voltage of 500 V, the plate dissipation is about 25 W for each tube (the KT88 is rated for 35 W). The correct bias condition is pre-set for the tubes supplied but will require adjustment if the tubes are replaced.
- Page 5 You may be told that the 6550 power tube can be substituted for the KT88. With its lower screen grid voltage rating, the 6550 is not recommended for the Stealth Max with its 500 V screen potential operating in either ultra-linear or triode mode.
-
Page 6: Specifications
Specifications___ Tube complement: 1 x GZ34/5AR4, 1 x 6SJ7, 1 x 6SN7GT, 2 x KT88 (matched pair). Rectifier : tube full-wave rectification with 5AR4/GZ34 cathode-type rectifier tube for soft startup. Output configuration: Class AB ultra-linear push-pull with fixed bias or triode mode. Phase inverter: cathode-coupled (long tail) Heater supply: ac Rated power output (4/8Ω... - Page 7 Mapletree Audio Design Stealth Max Monobloc Power Amplifier 240 VAC for Murray Smith © Co pyright Ll oyd Peppard 2008 Re v. July 12/08 KT88 +495 V 0.1/4 00 +493 V 6SN7GT 6SJ7/6SJ7GT +97 V 332 V 0.047/400 221K +69 V...
Need help?
Do you have a question about the Stealth Max and is the answer not in the manual?
Questions and answers