wwmhf
1000+ Head-Fier
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We had some discussion on the tube choices and some mods on the HLLY MKIII amp in another forum:
http://www.head-fi.org/forum/thread/496381/tube-options-on-a-clone-amp
This amp looks very much the same as Little Dot MKIII or MKIV. However, its circuit is closer to LD MKIV, and I think it is not exactly MKIV.
As it is, this amp has too many shortcomings to enjoy music. The first one is that the tube socket for the power tube on the left is not centered in the hole. I also observed this from the picture posted in Ebay’s ad. More critically, this amp uses inferior parts. I had troubles with several parts, see the report in the link above. Most of the caps are those types you never want them to be in your amps. I could not stand the sound at all so that I started modding it immediately. Some pictures and mods can be seen from the link above. By the request, I list below the information about the caps used in the final version of my modding:
I also did other things such as replacing important wires, pot, etc. Now, I can use the modified amp to enjoy music for hours. In conclusion: Do not buy this amp unless you can get it modded. It is not a clone of LD MKIII or MKIV. Modding tube amps is generally dangerous because of high voltage. In fact, the residual power in a big oil cap during my experiments caused damages to some other parts. Be careful!
http://www.head-fi.org/forum/thread/496381/tube-options-on-a-clone-amp
This amp looks very much the same as Little Dot MKIII or MKIV. However, its circuit is closer to LD MKIV, and I think it is not exactly MKIV.
As it is, this amp has too many shortcomings to enjoy music. The first one is that the tube socket for the power tube on the left is not centered in the hole. I also observed this from the picture posted in Ebay’s ad. More critically, this amp uses inferior parts. I had troubles with several parts, see the report in the link above. Most of the caps are those types you never want them to be in your amps. I could not stand the sound at all so that I started modding it immediately. Some pictures and mods can be seen from the link above. By the request, I list below the information about the caps used in the final version of my modding:
- All the low voltage electrolytic caps are replaced by Panasonic FC caps with the same values except for those two used in power supply for the driver tubes. For those electrolytic caps in the power supply of the driver tubes, much larger capacity Panasonic FC caps are used.
- The input coupling caps (two big caps besides the pot) are replaced by Solen film caps with the same value.
- The output coupling caps consist of 3 caps for each channel: A 330uf Rubycon electrolytic, a 2.2uf Wima polyester cap (the red cap in the picture), a Rifa 0.1uf cap (the smaller blue cap). These caps are put together in parallel. They are placed by a 330uf Rifa electrolytic, a 4.7uf Solen film cap, and a 0.1uf Wima polypropylene film cap. Then, I add another 0.01uf film cap for further bypass (the white caps in the picture with tube sockets).
- The 0.47uf interstage caps were (the larger blue caps) replaced by Dayton’s polypropylene film caps with the same value.
I also did other things such as replacing important wires, pot, etc. Now, I can use the modified amp to enjoy music for hours. In conclusion: Do not buy this amp unless you can get it modded. It is not a clone of LD MKIII or MKIV. Modding tube amps is generally dangerous because of high voltage. In fact, the residual power in a big oil cap during my experiments caused damages to some other parts. Be careful!
