502HTA - Hybrid Tube Amp
Product Update
The 502HTA is undergoing a thorough re-design to drastically improve noise, distortion and
thermal performance. Enhancements include:
thermal performance. Enhancements include:
- 80V Plate Voltage for more linear tube operation, especially with 12AU7, 12AX7 and 12AT7 tubes
- OPA551 Ultra-Low Distortion Power Buffers offer great performance and much lower temperature
- PCB Re-Design to better separate sensitive tube input section from the Pi 5V Rail
- Option Jumper allowing the 502HTA and PI to be powered separately
The 502HTA, designed and manufactured by Pi2Media (a division of PI 2 Design), is a High Quality I/O Shield designed to bring “Sweet Tube Sound” to the Raspberry PI ® family of Single Board Computers. The 502HTA enables the Raspberry Pi ® SBC to drive Headphones from 32 - 300 ohm with ease and fidelity.
The On-Board PCM5102A, 24-Bit @ 192Khz DAC drives the single stage 6DJ8 (aka 6922) tube. Class-A Output Buffer with Audiophile Grade IRL510 MOSFET and LM317A Constant Current Source drive the 3.5mm Jack. The dedicated 6.3V Heater Supply insures lowest crosstalk.
In addition, the 502HTA can be operated as a Stand-Alone Headphone Amp via the 3.5mm Line In jack. Use this with your phone to deliver Powerful, High Quality Sound to your favorite
Headphones!
The On-Board PCM5102A, 24-Bit @ 192Khz DAC drives the single stage 6DJ8 (aka 6922) tube. Class-A Output Buffer with Audiophile Grade IRL510 MOSFET and LM317A Constant Current Source drive the 3.5mm Jack. The dedicated 6.3V Heater Supply insures lowest crosstalk.
In addition, the 502HTA can be operated as a Stand-Alone Headphone Amp via the 3.5mm Line In jack. Use this with your phone to deliver Powerful, High Quality Sound to your favorite
Headphones!
Raspberry Pi Version |
Ceres - Standalone Version |
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Features
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Test Results
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Datasheet
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- 24-Bit DAC – The well regarded -112db SNR PCM5102 is used to convert the I2S Stream to drive the Single Triode Tube Stage at 24-Bit up to 192Khz Frame Rate
- TUBE ROLLING – The 502HTA supports both 6DJ8 (default is JJ 6DJ8) and 12AU7 type tubes. Individual Anode Bias Adjustment Pots plus selectable Series/Parallel Heater Configuration insure the perfect setup for virtually any tube!
- HEADPHONE OUT – Rugged 3.5mm Jack plus selectable output resistance between 1.5, 47 and 100 ohms.
- VOLUME POT AND GAIN SELECT – High Quality ALPS Potentiometer and dual Gain settings allow the user to adjust the output voltage to the optimal level for each Headphone.
- SINGLE POWER INPUT OPTION – A Single 24V @ 2A input powers the 502HTA and delivers 5V@3A to the Pi via Low Pass Noise Filter. Power can also be isolated between the 502HTA and the Pi for the lowest possible noise.
- STAND ALONE OPERATION – The 502HTA can also be operated in stand alone mode using the 3.5mm Line In Jack.
Downloads

visio-502hta_datasheet_p3.pdf | |
File Size: | 847 kb |
File Type: |

502hta_hw_ref_manual_p3.pdf | |
File Size: | 4676 kb |
File Type: |
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