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Wtb: JH990 op-amp

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3nity

Well-known member
Joined
Dec 30, 2005
Messages
3,527
Location
MTL, CANADA
I'm looking for 4 John Hardy 990.
If you have em unused lets put them to use.
Let me know thanks.
 

mobyd

Well-known member
Joined
Jan 27, 2006
Messages
169
Location
Auckland NZ
There is always the option of DIYing them - the schematics are widely available and the only slightly tricky to find bit is the LM394 dual transistor. These were done in a toaster oven.
 

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Mworthin

Active member
Joined
Apr 10, 2016
Messages
30
The current JH is a slightly modified Jensen 990. Hairball audio sells kits and finished Jensen 990s (DIY-990 Op-Amp Kit), and I cannot tell the difference between those and the Hardy’s in either the Lola or their Elements Gold preamps. The John Hardy’s are potted and there must be a lot of SMD parts in there, because they are noticeably lighter. Both discrete op amps sound amazing
 

kaltavilla

Member
Joined
Dec 18, 2017
Messages
6
I used to work for John Hardy back in the 90's. There is a very specific tuning process done during assembly. At least there was before he went to smd components, but I can't imagine that anything has changed other than the size of the components. He then burns them in for a few days, then they get potted, then they are tested again. Buy them from him, you will be guaranteed that they are performing to spec
 

Mworthin

Active member
Joined
Apr 10, 2016
Messages
30
I used to work for John Hardy back in the 90's. There is a very specific tuning process done during assembly. At least there was before he went to smd components, but I can't imagine that anything has changed other than the size of the components. He then burns them in for a few days, then they get potted, then they are tested again. Buy them from him, you will be guaranteed that they are performing to spec
Thanks for passing this on…this confirms everything I have read or heard about John. Fantastic attention to detail
 
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