• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

My new Preamplifier

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
My new Preamplifier

Introduction


HPA-1 uses Dual FET input, Dual transistor and Class A transistor. It has one balance and one unbalance input. The 4 layers circuit board is sandwiched between two copper templates. External power supply is convenient to choose any kinds of power supply.
Material


Circuit board 4 Layers plating
Transistor
Linear Systems LS843 (Dual FET)
Toshiba 2SA1349 (Dual transistor)
Toshiba 2SC3381 (Dual transistor)
Toshiba 2SA970
Toshiba 2SC2240
Toshiba 2SA1930
Toshiba 2SC5171
Resistance
Vishay UXB 0207 0.1% 10ppm (Instrumentation)
Vishay MMB 0207 0.1% 25ppm (Instrumentation)
Vishay RN55D 1% 100ppm
Precision Rssistive GP1/4 0.1% 50ppm
Capacitor
Philips 116 Aluminium electrolytic
Nippon Chemi-Con Aluminium electrolytic
Sanyo Aluminium electrolytic
Wima MKP2
Evox Rifa MMK
AVX Kyocera Ceramic
Johanson Dielectrics Ceramic
Integrated circuit
Texas Instruments LM317
Texas Instruments LM337
Texas Instruments NE5534P
Analog Devices AD847AQ (Ceramic PGA)
Potentiometer
Alps RK097
Selector
Alps
On/Off
Matsushita
Wiring
Quirkwire M16878 silver plated (Signal wiring)
Connector
Neutrik NC3FD-LX-HE (Top XLR connector)
Fischer connector S103 / Neutrik RCA
Neutrik NRJ6HM-1-AU (Top 1/4’’stereo jack)
Neutrik NAC3MPA (Power socket)

(Above components are subjects to change without prior notice)
Specifications

Level
10Hz → 100kHz ±0.5dbm (0dbm@XLR)
20Hz → 50kHz ±0.1dbm (0dbm@XLR)
THD+N
10Hz → 40kHz ±0.05% (0dbm@XLR)
Phase
1kHz < 0.03℃ 100kHz < 9℃(0dbm@XLR)
Gain
6.2dbm (0dbm@XLR)
Noise
10Hz -110dbm 1K -130dbm 10K -135dbm
(Neutrik A2D-Audio Measurement System)
Headphone


16Ω → 600Ω
Power Supply

DC ± 20V
(Internal regulator circuit, suitable for DC ± 20V→ 24V)
 

Attachments

  • DSC1.JPG
    DSC1.JPG
    150.2 KB · Views: 1,097
  • DSC2.JPG
    DSC2.JPG
    131.2 KB · Views: 1,047
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.