[xmdkq]

Please rest assured that in the summer of 40 degrees in Chengdu, we can do destructive testing for 8 hours without problems.

 

[SoLame]

Please rest assured that in the summer of 40 degrees in Chengdu, we can do destructive testing for 8 hours without problems.

Glad to see you here. I have an issue that maybe you (or any experienced users) can help me out.

I bought my 339 through Massdrop and received the amp a few weeks ago. I have already put over 50 hours or so on it. It sounds wonderful.

Last weekend while I was listening (the amp was already on for about 4 hours at that point), I heard a loud POP noise from the amp itself (no, it is not through my headphones). It sounded like what you hear when you squeeze an empty soda can. The amp continued to work okay, but I stopped using it anyway.

Then about 30 minutes or so after I turned it off, I heard the same POP noise. Because I was not using headphones (but I was sitting very close to the amp), I was sure that the noise is from one of the domes on the top of the unit.

What caused that loud noise? Anything I need to worry?

I hope someone can comment. Thank you in advance.

 

[Josh76]

I would contact either Massdrop or Yuking (I don't remember which provides support if you purchase from Massdrop). Even if the amp continues to work, that doesn't sound right to me.

 

[maheeinfy]

may be try running it from a power strip? in case if your power supply is the culprit

 

[SoLame]

I would contact either Massdrop or Yuking (I don't remember which provides support if you purchase from Massdrop). Even if the amp continues to work, that doesn't sound right to me.

may be try running it from a power strip? in case if your power supply is the culprit

Thank you, both of you. I've sent a message to Massdrop. I'm waiting for their answer.

Has anyone else had this problem?

 

[Josh76]

Has anyone else had this problem?

No, I've been really lucky so far (even with brands of questionable quality control).

Not implying 'questionable quality control' includes the La Figaro.

 

[xmdkq]

Can check whether the tube is ignited, whether the power indicator is on, and I have often encountered the problem of the tube.

 

[tintinsnowydog]

Please rest assured that in the summer of 40 degrees in Chengdu, we can do destructive testing for 8 hours without problems.

Thanks for the reassurance yuking! I've been looking at tubes, can your amp take 5A power tubes such as 6336B?

 

[MJS242]

Hi MJS242,

Any update on this?

Thanks

Let me follow up

 

[xmdkq]

Can be used, 6336 I have used.

 

[tintinsnowydog]

Can be used, 6336 I have used.

Thanks, does it need a special power supply?

 

[attmci]

Thought I'd post an update on the custom amp. Both the film and electrolytic capacitors I selected created size/space issues. Unfortunately, I didn't have a 339 on hand for measurements when I purchased the parts.

The diameter of the 6 top electrolytic capacitors was pretty large and so a non-standard bracket had to be created and other components shifted around.






One of the two film capacitors that needs to go under the center cover.



A larger cover had to be created to accommodate both of them.



Not a straight forward custom build but they seem up for the challenge and are good at solving these problems My original intent was to select parts/wiring that had a similar color but the availability of parts that meet the specifications can be difficult.

u r crazy.

 

[xmdkq]

No special power supply is required. Please pay attention to the power supply temperature of 339 during use.

 

[wwmhf]

I guess the answer to my question below might be negative, but ... here is the question:

Can we use 6SK7 instead of 6SJ7 in the 339 amp?

If yes, anything to be concerned?

 

[sup27606]

I recently acquired a LF 339 with a series of high end tubes including the TS 5998, RCA red, Philips 6SJ7WGT, Sylvania 7236 etc. I like the 5998 with the RCA reds for vocals and the pronounced bass, but the stellar combination so far are the 5998s with the Philips 6SJ7WGT. Compared to the RCA reds, the high end is more extended, noticeably bigger soundstage and clearer imaging. It sounds magical/holographic to me with the Sennheiser HD6XX, compared to the Schiit Jotunheim which sounds more 2D. I would like to try out a few other driver tubes to find if there is anything even better than what I have. I believe power tube wise, 5998s are the best one can get. I am curious about the EF86 and EF80. How are the sounds compared to the 6SJ7WGT? I appreciate bass with some tightness and texture (not a basshead) and treble extension with transparency, since I listen to quite a few classical albums. I am also a fan of jazz and vocals.