pucho812

interesting headphone amp, 100 dollar tube option....
« on: December 02, 2018, 09:42:19 PM »
I been thinking of a headphone amp for some time as the built in solutions I had on my uad converters were nothing stellar.   After  extensive looking I picked this  as the price was nice. $100.00 It has balanced inputs  1/4" headphone and 4 pin headphone connections,  and tubes. all made in china not chino. 
the circuit is a hybrid of tubes and 5532's.  Specs are not bad. So I get it in the mail today and fire it up.  First impression was it was nice especially for the price tag. The tubes run warm so looks like they are more for then show.  The stock tubes sounded o.k. and I was lucky to have  subs lying around that were a jan stock so I swapped them and got more pleasing results to my ear.
While I am  enjoying things,  this seems like the race to the bottom as far as electronics.  Perhaps I shall release a 99.00 dollar 1073 clone and really screw up the market.

https://www.amazon.com/LOXJIE-Balance-Amplifier-Headphone-Power/dp/B07H5JLD2Q
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.


scott2000

Re: interesting headphone amp, 100 dollar tube option....
« Reply #1 on: December 02, 2018, 10:54:03 PM »
What headphones are you using?

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #2 on: December 02, 2018, 11:21:58 PM »
What headphones are you using?

bayer dynamic dt770's are the bench test..
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #3 on: December 05, 2018, 02:55:46 PM »
test number two with sennheiser  280 and 300's as well as audio technica headphones. Compared to the stock UAD one in a UAD silver face, yes it was lovely.  At 99 dollars, it's very lovely. at 99 dollars and JAN tubes a total of an extra 20 dollars, was  well beyond what I expected.  I don't think I could DIY anything for less $$ with specs they tout. While I doubt the specs are as quiet as they say they are, it's more then close as there is no real hiss or anything of the sort.  over all very impressive especially for the price.

the race to the bottom is happening.
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

gyraf

Re: interesting headphone amp, 100 dollar tube option....
« Reply #4 on: December 06, 2018, 02:57:40 AM »
 ;D Schematics, or it didn't happen...!
..note to self: don't let Harman run your company..

pucho812

You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

Re: interesting headphone amp, 100 dollar tube option....
« Reply #6 on: December 06, 2018, 12:52:56 PM »
I remember seeing a similar headphone amp which used 5532s as VAS and a simple 12AX7 in a cathode follower configuration, If I remember correctly it sounded better without the tube with medium and high impedance headphones ::)

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #7 on: December 06, 2018, 03:26:03 PM »
Jakob,

here ya go.  8)

the ribbons go to the front panel lcd display and circuit board with volume control
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

scott2000

Re: interesting headphone amp, 100 dollar tube option....
« Reply #8 on: December 06, 2018, 03:32:53 PM »
Kinda sexy.... They even splurged on the caps???

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #9 on: December 06, 2018, 04:40:33 PM »
Kinda sexy.... They even splurged on the caps???

I know right.  :o 8)
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.


gyraf

Re: interesting headphone amp, 100 dollar tube option....
« Reply #10 on: December 07, 2018, 12:42:25 AM »
here ya go.  8)

the ribbons go to the front panel lcd display and circuit board with volume control

Thanks!

No schematic then? Is this an original design?

Driving 64 Ohms from the 6N3 without transformers  would be a no-no, so tubes are probably some kind of an input/distortion stage..?

Jakob E.
..note to self: don't let Harman run your company..

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #11 on: December 07, 2018, 11:13:38 AM »
Thanks!

No schematic then? Is this an original design?

Driving 64 Ohms from the 6N3 without transformers  would be a no-no, so tubes are probably some kind of an input/distortion stage..?

Jakob E.

I have not obtained one yet.   
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

living sounds

Re: interesting headphone amp, 100 dollar tube option....
« Reply #12 on: December 07, 2018, 11:32:32 AM »
Wow, insides look really nice, too. What's the B+ voltage? Is this a transformer to step up the voltage for the tubes?

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #13 on: December 07, 2018, 02:12:16 PM »
Wow, insides look really nice, too. What's the B+ voltage? Is this a transformer to step up the voltage for the tubes?

I'll take some measurements,  I assume the transformer is to step up for proper or close to proper b+
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.

PRR

Re: interesting headphone amp, 100 dollar tube option.... New
« Reply #14 on: December 07, 2018, 02:33:52 PM »
Driving 64 Ohms from the 6N3 without transformers  would be a no-no, so tubes are probably some kind of an input/distortion stage..?

There's 18 pins of tubes, and over 130 pins of chips. Looks like the tubes do less than 13% of the work.

The line of 8-DIP JRC chips next to the 1/4" jack suggests a chippy output. I can't read the types, but surely 30mA/amp, so 120mA peak to load, or over [email protected] dead-clean buffering. JRC makes even beefier opamps at low price.
« Last Edit: December 07, 2018, 11:01:07 PM by PRR »

pucho812

Re: interesting headphone amp, 100 dollar tube option....
« Reply #15 on: December 07, 2018, 03:20:57 PM »
There's 18 pins of tubes, and over 130 pins of chips. Looks like the tubes do less then 13% of the work.

The line of 8-DIP JRC chips next to the 1/4" jack suggests a chippy output. I can't read the types, but surely 30mA/amp, so 120mA peak to load, or over [email protected] dead-clean buffering. JRC makes even beefier opamps at low price.

the line of 8 dip are all 5532's
You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is.


 

Related Topics

  Subject / Started by Replies Last post
10 Replies
2160 Views
Last post February 17, 2005, 07:33:58 PM
by SonsOfThunder
17 Replies
3707 Views
Last post August 07, 2008, 02:46:40 AM
by Freq Band
4 Replies
3085 Views
Last post July 10, 2009, 06:19:24 PM
by pucho812
2 Replies
927 Views
Last post August 14, 2010, 10:13:17 AM
by pucho812