# Alpine PXA-H800 upgrade



## RoyAlpine

hi all,
I'm planing to upgrade my alpine PXA-H800.

as many people over world recommended i will start with replacing the opamps but instead of the OPA1642 i will put the new OPA1662,
for both Analog and Digital. ( all 23 of them, 8+15 )

in addition, i was recommended to replace the NICHON cap of PSU for Mundorf.

is there any more upgrades like caps, dac, etc... that you recommend to improve?

thanks.


----------



## kyheng

Guess another factor is you need to get matching pairs of the opamps.


----------



## RoyAlpine

Thanks for your advice, i also consider replacing all smd capacitors for elna silmic ii, do you think it is worthy? 

Sent from my GT-I9100 using Tapatalk


----------



## kyheng

Swapping the opamp will be a good start.
Next I'll try replacing NJR ICs. 
But I just check out both of the opamps you mentioned, I see they are not the same application? I may consider Analog Device's opamps also. Since same brand products may have same sound signature. 
BTW, H800 does not use DAC but using codec(ADC and DAC in a same package), so it may be much more complicated if you want to go this route.


----------



## thehatedguy

Depends on how crazy you want to go- reclocking, opamps, coupling caps, power supply filtering, lower noise/faster diodes, etc.


----------



## [email protected]

I would not put a mundorf in the power supply


----------



## RoyAlpine

thanks guys, as you know (or not) i'm living out of US and don't have any knowledge in electronics, but friend of mine works as solder (SMT most of time), so,
i just need an instructions which parts to replace... service manual will be helpful but i didn't found one, if someone sell, please let me know.

( next week i'm gonna order parts from Digikey )


@kyheng - AFAIK both opa1642 and opa1662 are both for same applications. (audio),
UNREALISTIC and NEIL puts the opa1642 and very happy with that.
Can you please send me link for IC's that will fit?

@thehatedguy - i'm trying go crazy as i can. 

@Scott - why not replace the PSU for Mundurf ? its better cap by far.


----------



## [email protected]

Changing out a PSU cap wont affect the sound. The Nichicon should be just fine there as that is a quality cap. It is Nichicon right? You spelled it differently up there. It looks like a Muse in the pictures. 

I would add DIP sockets if I was gonna change out OP amps, that way you can change in the future without soldering.


----------



## t3sn4f2

This should help.

http://www.diymobileaudio.com/forum/1991665-post1063.html

http://www.diymobileaudio.com/forum/1992068-post1073.html


----------



## soccerguru607

Those op-amps looks like surface mount package in picture


----------



## thehatedguy

Never seen a through hole to SMD adapter before.

If you want to recap the power supply, the Panasonic FC and FM caps are some of the best lowest ESR and ripple current parts out there. Elna Silmic II caps are really good electrolytic caps for the audio part. You could do some OS/Cons for the digital side of things.

You could reclock the whole thing with an external lower jitter clock.

Opamps, there are tons out there. You could get adapters and run 2 singles to replace the duals. Some headphone guys like different chips for different applications like the I/V conversion and gain stages.


----------



## [email protected]

soccerguru607 said:


> Those op-amps looks like surface mount package in picture


If that is the case, disregard my DIP socket comment, I only looked at the cap in the picture earlier


----------



## seafish

So just curious, what kind of actual listening or measurement improvements will these mods lead to?? 
NOT trying to be a devils advocate...I LOVE unique or advanced mods, just trying to learn more about this.


----------



## thehatedguy

You could potentially see a higher S/N ratio, faster slew rates, and less channel cross talk. But you would really want to have something like and Audio Precision machine to do the testing...or something similar.


----------



## seafish

Thanks for taking the time to answer.


----------



## Bluenote

Any updates?


----------



## RoyAlpine

not much for now,... planing to send the H800 to Matt R.


----------



## Bluenote

Good move! Looking forward to your impressions!


----------



## mmiller

Any updates?


----------



## RoyAlpine

no, its seems that Matt is busy so i have to find projects on the net, unfortunately, its looks like the only modification on the net is replacing OpAmp.


----------



## mmiller

Try contacting MCLSOUND on here. I believe he knows someone that mods/fixes equipment.


----------



## thehatedguy

Jeremy Carlson has done a lot of things for me years a go...and he has done a lot of work for Scott Buwalda. He's on the Hybrid Audio forums as jc2. I was thinking about emailing him to do a few opamp and cap changes on my Zapco amp.


----------



## mmiller

Thanks Jason.


----------



## thehatedguy

jcarlson at hybrid - audio dot com


----------



## RoyAlpine

Good news, Matt sent me an email that it will takes time but he will help me,
meantime, another project gonna starting, just sent a PM to MCLSOUND,
i want to upgrade my Helix Competition amps.


----------



## evo9

thehatedguy said:


> Never seen a through hole to SMD adapter before.
> 
> If you want to recap the power supply, the Panasonic FC and FM caps are some of the best lowest ESR and ripple current parts out there. Elna Silmic II caps are really good electrolytic caps for the audio part. You could do some OS/Cons for the digital side of things.
> 
> You could reclock the whole thing with an external lower jitter clock.
> 
> Opamps, there are tons out there. You could get adapters and run 2 singles to replace the duals. Some headphone guys like different chips for different applications like the I/V conversion and gain stages.





[email protected] said:


> If that is the case, disregard my DIP socket comment, I only looked at the cap in the picture earlier


They exist! Just got to know where to look.

http://www.accutekmicro.com/pdf/ProductPDF-378.pdf

http://www.accutekmicro.com/pdf/ProductPDF-380.pdf

http://www.accutekmicro.com/products/products-detail.cfm?CID=53


----------



## evo9

Pictures!


----------



## thehatedguy

Neat! I would like to get some of those to try in my Zapco amp.


----------



## soccerguru607

Wondering if you can separate socket and circuit board piece. Would be easier to solder them.


----------



## evo9

^^^ There is that option to unplug the upper half! But I'm not sure if it is available on the model I pictured. Call Accutek to find out. They do sell direct! A bit pricey but you get what you want.


----------



## blickman12

What benefits does these upgrades hold to the H800? Also, is there any member on here that will do the upgrades or is reputable for doing so? What would be a going rate for it as well?


----------



## BillC

Did you ever follow through with the planned modifications?


----------

