Hello,
Just got this brand new, still in the box:
Not the SE version But I want to upgrade all the "stuff"...
Anyone have a schematic for thie op amp version?
Thanks in advance.
Alex
Just got this brand new, still in the box:
Not the SE version But I want to upgrade all the "stuff"...
Anyone have a schematic for thie op amp version?
Thanks in advance.
Alex
Question:
This is is the upgrade list from BigSkyAudio
C2, C102 = 150pF polystyrene (220pF in early units)
The caps in my unit are 100pf...so just get the poly caps for 100pf or up to 150 or 220pf?
Thanks
Alex
This is is the upgrade list from BigSkyAudio
C2, C102 = 150pF polystyrene (220pF in early units)
The caps in my unit are 100pf...so just get the poly caps for 100pf or up to 150 or 220pf?
Thanks
Alex
These 100pF caps on your unit are very nice polypropylene foil, no reason to replace them. Replace the input caps (0.22uF polyester) with good quality 1uF electrolytics.
Replace the input caps with at least .33uF WIMA polypropylene... way better than an electrolytic.
Purchase a Burr-Brown OPA2604 from Michael Percy Audio. It is the best option for the opamp. We performed this upgrade on dozens and dozens of these OBH-11 headphone amplifiers over 13 years with great results with plenty of positive customer feedback. Be sure to use a linear regulated 24-volt DC power supply too.
Ok I sent Michael a message just now. He also sell the Holco resistors...
The input caps: WIMA's...
The input caps: WIMA's...
Yes, replace the input caps (C1, C101) with .33uF (330n) WIMA MKP2 polypropylene. Check Mouser for them. I would leave C2, C102 as is. My upgrade sheet listed the values just for reference, not that they needed to be replaced. Michael Percy may be out of Holco 22k but I may have some left in my stock.
In the upgrade list C12 is called out for a 100uf/35v Panasonic FC electrolytic.
On my OBH11 V2 C12 is a 47uf 35 v sanwa,
Ok to replace with the 100 uf ?
On my OBH11 V2 C12 is a 47uf 35 v sanwa,
Ok to replace with the 100 uf ?
Another question is my C6 and C106 are these BLUE items
I can tell if they are 22pf or 47 pf...
Does it matter here?
Are these good enough or do u think they should be changed out?
Thanks
Alex
Ready to send Mouser the order once I get these last two issues resolved
Then look for a 24vdc linear wal wort supply
I can tell if they are 22pf or 47 pf...
Does it matter here?
Are these good enough or do u think they should be changed out?
Thanks
Alex
Ready to send Mouser the order once I get these last two issues resolved
Then look for a 24vdc linear wal wort supply
Absolutely ok. It is merely power supply bypass for pin 8 (V+) to the opamp. The Panasonic cap is of higher quality than what is provided stock.
C6, C106 in my amp are polystyrene from the factory. Nice quality and no need to change them. I am not sure what composition the ones in your amp are.
The photo shows the complete upgrade I installed.
The photo shows the complete upgrade I installed.
Attachments
Last edited: