fubar3
100+ Head-Fier
- Joined
- Jul 16, 2011
- Posts
- 249
- Likes
- 12
This is an economy amp purchased for it's case, not it's contents, thinking it would save casework on the next DIY. However, I find that it is good quality amp worth a look for anyone who wants satisfactory performance on a tight budget. Found on Ebay = $34.50 + $8.50 air mailed from Hong Kong.
The amp arrives in a factory box with universal 18vdc supply and phone plug adapter. There are more photos on the HA-INFO site but I include the circuit board which has SMD resistors vs the web site which has axial resistors.
Sound: Initially, this amp sounded "brighter" than my others. It seemed to have voice sibilance and a faint echo on music with cymbals. For example, turn on your equalizer with flat settings and then boost the 14k-16k frequencies. I tend to dislike sounds in this region. However, after much experimentation with amps, headphones, and music, I could find no conclusive difference. I suppose burn-in might be true after all
. Bass output is very good from this amp.
Design: This amp has a minimalist design with only 2 active components. There is a TDA2030 18W amplifier which splits 18vdc to +/-9vdc. The driver is a TPA6120 which has been discussed on Head-FI in the past. It is a current-feedback-amplifier, CFA, which gives good performance but requires more sophisticated design skills than the common voltage-feedback amps. Note the 330pf blue caps on the circuit board. The CFA is very sensitive to capacitance and has a 50ohm resistor between the input pins and the volume control. However, the blue caps shunt the input pins. So I think this might be a mistake. Perhaps I will remove them and test later.
This amp has too much gain such that I never turn the volume control more than 1 quarter. At 1 half turn there is 10mv offset on the phone jack. I believe the amp would effectively drive high-impedance phones, mine are 32 or 55.
There are slots in the side of the case. Perhaps this is irrelevant to it's purpose.
The amp arrives in a factory box with universal 18vdc supply and phone plug adapter. There are more photos on the HA-INFO site but I include the circuit board which has SMD resistors vs the web site which has axial resistors.
Sound: Initially, this amp sounded "brighter" than my others. It seemed to have voice sibilance and a faint echo on music with cymbals. For example, turn on your equalizer with flat settings and then boost the 14k-16k frequencies. I tend to dislike sounds in this region. However, after much experimentation with amps, headphones, and music, I could find no conclusive difference. I suppose burn-in might be true after all
Design: This amp has a minimalist design with only 2 active components. There is a TDA2030 18W amplifier which splits 18vdc to +/-9vdc. The driver is a TPA6120 which has been discussed on Head-FI in the past. It is a current-feedback-amplifier, CFA, which gives good performance but requires more sophisticated design skills than the common voltage-feedback amps. Note the 330pf blue caps on the circuit board. The CFA is very sensitive to capacitance and has a 50ohm resistor between the input pins and the volume control. However, the blue caps shunt the input pins. So I think this might be a mistake. Perhaps I will remove them and test later.
This amp has too much gain such that I never turn the volume control more than 1 quarter. At 1 half turn there is 10mv offset on the phone jack. I believe the amp would effectively drive high-impedance phones, mine are 32 or 55.
There are slots in the side of the case. Perhaps this is irrelevant to it's purpose.