Inside PJ. MIAOLAI SA-1000 tube preamplifier. 

Hello and thank you!

Thanks for the tip! I will play with some other tubes for sure :)

Hope you'll enjoy it!

Thanks for the information!

Thank you @@EBSELPROAUDIO :)

What exactly don't you like? Maybe some of those vices can be remedied by different tubes?

@@NormcoreGreg it's hard to explain, the sound became unpleasant. I assume it sounded like the distortion on some frequencies (possibly upper midrange). I haven't experimented whith the preamp a lot, maybe someday I'll get back to it

In my opinion the headphone amp in the preamp I reviewed is just a convenience addition. I will be reviewing two dedicated headphone amps from Fosi soon, one of which includes a tube section, so you might want to stick around ;-)

@@NormcoreGreg Sounds good. I look forward to it.

I couldn’t find any on Aliexpress. Can you share a link to the dynavox preamps? I’ll see what I can do.

I treat this as a compliment :D

hilarious

@@NormcoreGreg As long as you don't get angry and turn green! You get a small amount if we buy it ... isn't that compromising you a tiny bit? Moreover, you looked at the components and build quality and didn't cover the important part, how it sounds. The tubes come from Russia ... is that a potential export embargo violation?

@@henrikcarlsen1881 these are all valid questions, thanks! :) As for the sound of it, I talked about it in my original review of this unit, which you can find here - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-v6KvBmASEYE.html. Regarding the commission (that I'm yet to see) and how it might influence my opinions - I'm an amateur "youtuber" and I do it purely for fun; I purchase all the gear I talk about with my own money (except for three pieces I recently received for free as review units) and make some research before to make sure it's not total crap; having said that I admit that a potential financial reward, however small it might be, may, even on the subconscious level, affect my opinions. But no one's objective anyway and we should always take any information with a grain of salt. Your last question about tubes from Russia - as a Pole I wave a very strong opinion about Russia and how it should be dealt with, especially given the ongoing war with Ukraine. However, I'm not sure such tubes are of strategic importance. Also, I'm not sure if they come from Russia or from some other ex-soviet country, e.g. Ukraine. I appreciate your concerns in this matter though.

​@@henrikcarlsen1881are you serious, there always has to be one

It doesn’t look like those opamps are swappable. At least not easily. But you can roll tubes - that’s what they’re for besides the look ;)

@NormcoreGreg i guess at this price point, rolling opamps is too much of an ask.

@NormcoreGreg Yes, will check on tube rolling. Appreciate if you can provide some alternatives for the tubes in an upcoming video.

Why not? If opamps are soldered to the pcb, then desolder and solder proper sockets to make further exchange easier. I've done such thing several times.

@@enricolisk1357, @dungysphincter7974 mentioned several choices in his comment to this video: "Here are some replacement tubes if you want to tube roll (GE 5670W, 6N3/6H3N/396A /2C51/5670. For best life, and lowest noise, I recommend the Soviet 6H3n-EB tube over the 6H3n-E tubes."