Hi Guys,
Ramr asked me to do a comparison between this Mosfet amp and the Ovation NX. I finally got time today and hooked both amps up to my A/B setup. This amp is running on +-44V and the NX on +-47V. Both PSU's have 20,000uF filters per rail.
After listening for about 5 hours I find no audible difference between the two. Both are extremely clear with tight solid bass. Everything I played through them sounds wonderful.
Blessings, Terry
Ramr asked me to do a comparison between this Mosfet amp and the Ovation NX. I finally got time today and hooked both amps up to my A/B setup. This amp is running on +-44V and the NX on +-47V. Both PSU's have 20,000uF filters per rail.
After listening for about 5 hours I find no audible difference between the two. Both are extremely clear with tight solid bass. Everything I played through them sounds wonderful.
Blessings, Terry
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How about comparing Mooly's amp with Mooly's amp. Such comparison will usually yield stronger differences than comparing apple with orange 🙂 Try to replace the 2N5401 input transistor with 2SA1015 GR.
Yes
I just said it sounds as good as the NX. Why would I want to change it? I did this comparison by request. I only shared my findings for those who might be interested. Not to create more work for myself. 😉
Hehehe you said "no audible differences" and I just found that it is strange 😀 Because when I build stereo stuffs, tweeter, woofer, speaker, amps, the left one is hard to be made the same with the right one 😀
The low noise A1015 GR (Vce=50V) at input stage is only a clue, where small change can create audible difference.
A1015 with Vce=50V is the highest Vce rating low noise transistor that I know. If you think it is not save (due to unreliable current production), don't you think it is a good idea to bring voltages down so we can use low noise transistor, especially at the input.
I'll find out about the Hitachi...
For many years, 2SC2240/A970 have been the undisputed BJT champs at low noise/high voltage applications in the input stage.
Now we use KSC1845/A992 as the only equivalent THT pair still in production. I think though, by trying to use common obsolete parts or those extracted from old consumer equipment, you would limit your design options and the ability to know what others are hearing.
These sell for US 0.33 ea/1 or $0.10 ea/100 from Mouser and probably not too expensive for small quantities through their local representatives or those of Digi-key, RS, Farnell etc.
I have many of those you mentioned (but I'm curious with the Toshiba Mooly had mentioned). There is discussion about vintage amp versus modern amp...
IMO, if only manufacturers have the incentive to produce special transistors for audio (especially for the VAS), amps will be a lot better than ever. I found that in producing a good amplifier nowadays, nothing can beat a good choice of superior transistors.
Sorry to but in; and to save me searching 600odd posts, is there a PCB for this amp?
I'd like to see how it compares, in my forgettory, to the JLH from all those years ago.
I'd like to see how it compares, in my forgettory, to the JLH from all those years ago.
Good audio transistors, even the obsolete 2SC2240 etc. are still in production by Toshiba and there are plenty of good discrete parts for use anywhere in audio products. The catch is, that the new small signal and medium power devices are for SMT boards and we DIYs, who generally prefer the old THT parts, have been left behind with a shrinking number of legacy parts, many of them poor copies from other manufacturers or just fakes
Anyone doing boards ?....I don't really want to start or learn how to many new things I'm learning
Lawrence
Boards available
Hello Alex, do you happen to have a few boards(stereo) available for me?
Lawrence
Hello Alex, do you happen to have a few boards(stereo) available for me?
Lawrence
no disrespect sir
Hello Terry, seen you in many amp building threads you have built a ton! and so i see that there seems to be no difference in sound in a lot of your builds this indicates that there is something in your front end player or speaker covering up the differences maybe its time to DIY a speaker or preamp or front end etc...you get the idea...
again I mean no disrespect but your talents deserve more... there are major differences between amplifiers i assure you.
Lawrence
Hello Terry, seen you in many amp building threads you have built a ton! and so i see that there seems to be no difference in sound in a lot of your builds this indicates that there is something in your front end player or speaker covering up the differences maybe its time to DIY a speaker or preamp or front end etc...you get the idea...
again I mean no disrespect but your talents deserve more... there are major differences between amplifiers i assure you.
Lawrence