Tomo
DIY tube amps can be SHOCKING
- Joined
- Jun 22, 2001
- Posts
- 1,067
- Likes
- 14
Hi,
I think I started to build the very first amp I have ever built again 2 months ago. Well ... I just finished today. So here you go.
This is a simple as you can get Szekeres Amp. This amp is built in the belief that voltage gain is not necessay for low impedance can. Recent few years, sources have become more and more efficient and their output level climbed high. It is now rare to see CDP outputing less than 1V in the line-out. If you are fool enough (like me) to plug Gain 10X amp to the line-out, you should have nearly blew your head off (or at least throw off of your chair). So we go 0-dB ... Gain 1X.
Component values are changed so I can use parts from my stock. Only modification I have made is the PSU bypass. It uses one OSCON 100uF per channel and two 2200uF HFQ (dual-mono). PSU is external. Generic Metal-Film Resistors. Nobel 50K.
Amp is entirely done Point-to-Point. No board. Which makes sense since I used very big parts here. PSU wiring got screwed up because I wasn't planning on using this particular chasis (which is COOL) and having R on top and L on bottom chasis. Note also the MOSFETs are bolted to the chasis which is why you don't see those infernal heatsinks.
Although the wiring level is amature to say the least, since the amp has no voltage gain and I created very nice solid grounding, it is silent. The electrolytic coupling caps are GENERIC. Despite what is being said, if you keep the caps small, the effect is negligible. (And, the leads won't support ENLA or BG which tend to be larger. OSCON's small, but too expensive for me.)
I have to wait for few days before, the caps "burn-in." But I can hear it is very nice sounding with Senn PX100. As expected LOW-END is stronger; as a buffer it increases the current that the headphones can eat. HIGH comes out fairly transparent. This is a surprise since generic electrolytics aren't known to show that character. It could be the result of using much tightly packed polypropylene caps (Siemen MKP 0.47uF) instead of SOLEN 4.7uF.
On a personal note, I really enjoyed building Szekeres amp again. It is very simple and takes very little time. And this time, I gave it a chasis it deserves. I feel embarrassed, but I am feeling a great sense of accomplishment. ... I feel like I built the great wall of china by myself.
Tomo
I think I started to build the very first amp I have ever built again 2 months ago. Well ... I just finished today. So here you go.
This is a simple as you can get Szekeres Amp. This amp is built in the belief that voltage gain is not necessay for low impedance can. Recent few years, sources have become more and more efficient and their output level climbed high. It is now rare to see CDP outputing less than 1V in the line-out. If you are fool enough (like me) to plug Gain 10X amp to the line-out, you should have nearly blew your head off (or at least throw off of your chair). So we go 0-dB ... Gain 1X.
Component values are changed so I can use parts from my stock. Only modification I have made is the PSU bypass. It uses one OSCON 100uF per channel and two 2200uF HFQ (dual-mono). PSU is external. Generic Metal-Film Resistors. Nobel 50K.
Amp is entirely done Point-to-Point. No board. Which makes sense since I used very big parts here. PSU wiring got screwed up because I wasn't planning on using this particular chasis (which is COOL) and having R on top and L on bottom chasis. Note also the MOSFETs are bolted to the chasis which is why you don't see those infernal heatsinks.
Although the wiring level is amature to say the least, since the amp has no voltage gain and I created very nice solid grounding, it is silent. The electrolytic coupling caps are GENERIC. Despite what is being said, if you keep the caps small, the effect is negligible. (And, the leads won't support ENLA or BG which tend to be larger. OSCON's small, but too expensive for me.)
I have to wait for few days before, the caps "burn-in." But I can hear it is very nice sounding with Senn PX100. As expected LOW-END is stronger; as a buffer it increases the current that the headphones can eat. HIGH comes out fairly transparent. This is a surprise since generic electrolytics aren't known to show that character. It could be the result of using much tightly packed polypropylene caps (Siemen MKP 0.47uF) instead of SOLEN 4.7uF.
On a personal note, I really enjoyed building Szekeres amp again. It is very simple and takes very little time. And this time, I gave it a chasis it deserves. I feel embarrassed, but I am feeling a great sense of accomplishment. ... I feel like I built the great wall of china by myself.
Tomo
