Reverse Engineering of a Chinese Tube Headphone Amp

[amirm]

My favorite electronic blogger, Dave Jones, does a reverse engineering of a Chinese (cheap) tube headphone amp. You may not be interested in the product but the process of how we reverse engineer audio gear may be useful. It is only 26 minutes so not long:

 

[NorthSky]

It looks like this one: http://www.soundandvision.com/content/tube-amps-pocket-change-nobsound-ns-08e#cjka5WU08uxcEZmT.97

 

[RayDunzl]

You may not be interested in the product

They're cheap enough, Approximately US $42.51 plus $2 shipping from Hong Kong.

There may be better bargains, I'll keep looking.

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Having watched a sliver of the video I'll pass. He is entertaining as well as informative.

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Here's the scope he's using:

https://www.amazon.com/Rigol-DS1054Z-Digital-Oscilloscopes-Bandwidth/dp/B012938E76

I can't figure out what additional features it has from reading about it and being ignorant of the base feature set on new scopes.

 

[DonH56]

I'd be a bit nervous about placing all those little electrolytics near the tubes.

That's a pretty impressive DSO for the money. I keep wanting to get test equipment but no time for play these days. I like the DSO's we have at work but since they run $250k ~ $500k they are a bit out of my budget... Even the cheap models run $10k+ these days.

 

[BobShermanEsq]

Not actually a tube amplifier. More like... We have buildings full of worthless tubes let's find something to do with them.

Used properly tubes can be wonderful devices, sad many know so little about them these days.

 

[Thomas savage]

Not actually a tube amplifier. More like... We have buildings full of worthless tubes let's find something to do with them.

Used properly tubes can be wonderful devices, sad many know so little about them these days.

Still very popular with audiophiles, increasingly so in recent times I would say!

 

[RayDunzl]

Not actually a tube amplifier.

I would agree it is a bit deceiving..

Looks sorta like one, so that may be enough for the hipsters.

 

[amirm]

Here's the scope he's using:

https://www.amazon.com/Rigol-DS1054Z-Digital-Oscilloscopes-Bandwidth/dp/B012938E76

I can't figure out what additional features it has from reading about it and being ignorant of the base feature set on new scopes.

Dave Jones is the #1 blogger in electronics. He quit his day job and makes his living this way. Instrument makers shower him with products given his huge influence. He has a suite of scopes. The Rigol 1054Z that he is using in this video has a combination of superb value and good quality. It is by far the best recommended scope for hobbyists. It can also be hacked to unlock the rest of its features including higher bandwidth which makes it even more attractive to hobbyists.

 

[NorthSky]

Dave Jones is a very cool guy; and some folks are afraid of him...I wonder why.
He's one of my favorite audio scientist gurus. Plus I love his sense of humor...his style

 

[RayDunzl]

The Rigol 1054Z that he is using in this video has a combination of superb value and good quality.

Let's see what Dave says...

 

[amirm]

Didn't I say the same thing? I think I did.

 

[TBone]

Didn't I say the same thing? I think I did.

perhaps; sans visual bias, quirky characteristics, and wanky tonality ...

 

[Thomas savage]

Struth mate, it all just wank

Amir how come he is wearing your t- shirt?

 

[amirm]

Amir how come he is wearing your t- shirt?

Should have trademarked the darn line.....

 

[NorthSky]

Let's see what Dave says...

Should it be a requirement that all AudioScienceReview members buy one before they are permitted to post here?

 

[amirm]

Should it be a requirement that all AudioScienceReview members buy one before they are permitted to post here?

Buying is the easy part, knowing how to use it the difficult part.

And no, a scope is of no value to membership here. Unless you are designing electronics, or doing deep diagnostics, it is not what you should purchase.

Members here should buy a measurement microphone and learn how to use it to measure their speaker+room.

 

[DonH56]

I want one.

 

[NorthSky]

Which mic(s) would you recommend Amir?

 

[NorthSky]

I want one.

A scope or a mic?

 

[RayDunzl]

MiniDSP UMIK-1 ($75+$20 s/h from HongKong) is a safe choice in my opinion, plug and play with REW software for measurement.

The PC recognizes it:



REW recognizes it, reads the calibration file and no further fiddling is needed for reasonably accurate performance. I don't see a problem. It's (maybe) a little noisier than a more professional solution, but it doesn't obstruct taking useful measurements at normal levels


Cross Spectrum Labs sells them (when they have them), maybe with a better calibration file (that's their claimed specialty).