[Nankai]

There are so many new concept appearing now. I believe it is right time to build new amp module for HM-801. I wish headfiers can give us any good advice.
 
So far I have two ideas:
Possibility 1: Balanced design
Possiblity 2: Six Channels design for JH Audio

 

[Edwood]

Regarding the upcoming JH Audio JH-3A....
 
You should definitely work with Matt Macbeth with Cypher Labs / GR9 Technologies.  He's the one that's developing the DSP Active Crossover Amplifier for the JH-3A.  Since it's more than just an amp, it will likely require extensive modifications to the existing HM-801 layout, as it has a digital volume controller and digital control of bass levels.  Also the headphone connector is completely different for the JH-3A, it's an 8 pin circular DIN connector.
 
Another one would be integrating the HeadAmp Pico Slim into the HM-801.  But like the JH-3A, it presents the problem of digital volume control.  The Pot could be directly wired to, but again, would be a semi-permanent mod and not a simple Gan-Qi card swap.
 
One way to address these volume control issues would be to have a new Gan-Qi metal cover.  With the JH-3A version, it could have those two toggle dials protruding out the back, inside slots cut out of the rear.  
The Pico Slim version could have a single opening for a rotary pot.   But I think going with a semi-permanent mod of having the pot directly wired would be much better.
 
Overall, I think an internal Pico Slim would be the "easiest" of all the proposed amp modules, as it does not require a new headphone output socket, unlike a Balanced output or 6 Channel JH Audio output.
 
-Ed

 

[El_Doug]

assuming these amp designs are possible... how would the alternate output connectors be incorporated? 

 

[mrarroyo]

Edwood by your comments I assume you find the Pico Slim to be an amp you enjoy as well or better than the amp module in the HM-801. I do look forward to hearing a Pico Slim which must be an awesome amp, I say this because I find the sound out of the HM-801 to be superb and if the Pico Slim improves on it ... Well lets say it must be special indeed.
 
Fang, today I listened to the HM-801 via a Yuin OK1 and not only was I impressed so was a coworker. He stated that he only has heard such a good sound while seating at home and using a fine set of speakers.

 

[Tidus]

Fang i like both ideas.

 

[warp08]

Quote:

There are so many new concept appearing now. I believe it is right time to build new amp module for HM-801. I wish headfiers can give us any good advice.
 
So far I have two ideas:
Possibility 1: Balanced design
Possiblity 2: Six Channels design for JH Audio

 

• I assume you'd like to replicate a "Protector"-like module into the HM-801.  Since quite a few people are using the HFM-801 with the Protector instead of either of the built-in amp modules, this idea definitely has potential
• Do you mean a triple op-amp design + active crossover circuitry to accommodate the JH-3A paired JH13/JH16 Pros shipped without a crossover?  You'd need to modify the chassis to include an XLR connector to accommodate it.  It would still not have the DSP circuitry so how would tuning be done?  Or are you thinking of designing a six channel design similar to the JH-3A concept but without the DSP/Active Crossover configuration and instead supplying your own, modified IEMs with it?

 
Regardless, I'm glad to see that development is continuing on the HF platform, Fang.  That is great news!

 

[fil]

Quote:

• I assume you'd like to replicate a "Protector"-like module into the HM-801.  Since quite a few people are using the HFM-801 with the Protector instead of either of the built-in amp modules, this idea definitely has potential

 
I second the 'Protector-or-similar amp module for the HM-801' idea. Provided it is reasonably priced, I would buy it in a heartbeat.

 

 

[testrichard]

Quote:

Regarding the upcoming JH Audio JH-3A....
 
You should definitely work with Matt Macbeth with Cypher Labs / GR9 Technologies.  He's the one that's developing the DSP Active Crossover Amplifier for the JH-3A.  Since it's more than just an amp, it will likely require extensive modifications to the existing HM-801 layout, as it has a digital volume controller and digital control of bass levels.  Also the headphone connector is completely different for the JH-3A, it's an 8 pin circular DIN connector.
 
Another one would be integrating the HeadAmp Pico Slim into the HM-801.  But like the JH-3A, it presents the problem of digital volume control.  The Pot could be directly wired to, but again, would be a semi-permanent mod and not a simple Gan-Qi card swap.
 
One way to address these volume control issues would be to have a new Gan-Qi metal cover.  With the JH-3A version, it could have those two toggle dials protruding out the back, inside slots cut out of the rear.  
The Pico Slim version could have a single opening for a rotary pot.   But I think going with a semi-permanent mod of having the pot directly wired would be much better.
 
Overall, I think an internal Pico Slim would be the "easiest" of all the proposed amp modules, as it does not require a new headphone output socket, unlike a Balanced output or 6 Channel JH Audio output.
 
-Ed

wow Ed you really are resource-full and knowledgeable, how did you find that out?
 
dont wanna sound stupid but perhaps just a possibility here ??
 
since HiFiman does have and using software to change songs ( i mean it does have a digital UI ), could we also use it for digital volume or bass controller ? i mean if we are talking about digital then its already there right ? just press the gold button to tune up or down~
 
of course i dont know the gan-qi design so i dont know if Gan-qi slot is only for simple musical purpose and does not have the capability to function like a add-in as Display card to PC ( i mean does it capable of communicate to each other? or it just one way communication such as the Gan-Qi act as Amp board to 801 ? dont shoot me as i really dont know Audio Hardware or electrical stuff~ i have 3 degrees but Audio is not one of them even though one of them is IT )
 
as for people think that defect the purpose of having analog volume control ? i think they can both co-exist ~ because when i use 801 as Desktop DAC, i set my window volume to 75% while adjust my 801's analog volume to suit my hearing !! through the phone out of course as the line out volume would determine by window volume control i think

 

[Edwood]

I prefer to have separate, discrete volume control independant from software/menu.
 
The biggest problem to solve with any of these potential Amp Modules (except for the Pico Slim) is the headphone output jack.  Both the Balanced and the JH Audio 6 Channel designs require a different headphone jack.  So they will require hardware modifications to the HM-801 or modified Gan-Qi door, or some kind of dongle adapter.
 
-Ed

 

[testrichard]

point Taken Ed ~
 
i agree as i cant imagine how to place the output jack for the balanced amp without totally change the 801 casing, sure every one thought about having balanced amp long before JH3A concept is out but stuck at the output jack
 
all i can said is " surprise us , Fang ~ as you did it before " lol

 

[Bojamijams]

Honestly I would take anything at this point. I NEED more then whats currently available. Pico slim would be the easiest but I have a JH-13 so I would definitely enjoy either a balanced protector or the jh-3a

 

[El_Doug]

A new amp module door with a simple cutout would possibly work, with a pcb-mounted headphone jack... or would this put too much stress on the pcb during insertion? 
 
I'd DEFINITELY be interested in a balanced amp, first and foremost.  The GAME is, I believe, really rather good - and certainly removed all the noise that the stock amp had, so I wouldnt really be interested in yet another SE option

 

[testrichard]

Quote:

Honestly I would take anything at this point. I NEED more then whats currently available. Pico slim would be the easiest but I have a JH-13 so I would definitely enjoy either a balanced protector or the jh-3a

u should enter the 9mm custom IEM give away~~ you will be one of ideal guy to write a review/impression for the up coming Head-direct custom IEM

 
 
(i cant delete it now, just realize all too many JH owner here and all should/qualify for writing great impression/review. so please check the thread for your chance and i look forward for every one's post)

 

[testrichard]

 
Quote:

A new amp module door with a simple cutout would possibly work, with a pcb-mounted headphone jack... or would this put too much stress on the pcb during insertion? 
 
I'd DEFINITELY be interested in a balanced amp, first and foremost.  The GAME is, I believe, really rather good - and certainly removed all the noise that the stock amp had, so I wouldnt really be interested in yet another SE option

or may be could left out the module door? industrialize the new module to fit perfectly with out module door, like sliding N64 game cartridge into N64 console etc and you could even make the module larger with pop out end ?

 

[ade_hall]

How much better is the Pico Slim over the 801 modules?