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Listing of Opamps for EE Minimax DAC Plus

Phil from Cimmaron Technology sent me a list of approved Opamps for
respective positions on the board of the EE Minimax DAC Plus; prices
include the Brown Dog Adapters provided by Cimmaron. I have been using
in the U1/U2 position the OPA2604 and in the U6/U7 position the OPA827.
I have not Opamp rolled this unit much, as I have been busied with other
components for review. I attest that the DAC Plus in SS output with the
tube removed and these opamps is sensational.

(NOTE CAREFULLY the warning at the bottom NOT to use the AD 8620 in the U1/U2 positions!) Also note that the positioning of the opamps/adapter is always with the small square solder point on the topside of the Opamp at the upper right hand when the unit is facing the installer. Finally, it is recommended that an opamp extraction tool and an anti-static device be used when removing/installing Opamps.

Is it "worth it"? YES! YES! YES! :)

RECOMMENDATIONS OF OPAMPS FROM CIMMARON TECHNOLOGY:
For U1/U2
Single-channel op-amps mounted on the 020302 SO8-to-DIP8 single-to-dual
channel adapter:
qty 2 each required

020302-OPA627 $48.00 x 2 = $96.00
020302-OPA827 $38.00 x 2 = $76.00
020302-AD797B $48.00 x 2 = $96.00

. . . also for U1/U2
Dual-channel op-amps mounted on the 970601A SO8-to-DIP8 adapter
qty 2 each required

970601A-AD8620 $23.00 x 2 = $46.00
970601A-OPA2604 $13.00 x 2 = $26.00
970601A-OPA2134 $10.00 x 2 = $20.00

For U6/U7
Single-channel op-amps mounted on the 970601A SO8-to-DIP8 adapter
qty 2 each required

970601A-OPA627 $28.00 x 2 = $56.00
970601A-OPA827 $23.00 x 2 = $46.00
970601A-AD797B $23.00 x 2 = $46.00

The AD 8620 should not be used in the DAC PLUS.
"On some forum there was a suggestion to use the AD8620. for positions U1
and U2. While this is a dual op-amp, it is only rated to use up to
plus/minus 13 volts. The circuit in the EE Mini Max DAC and DAC Plus is
plus/minus 15 volts."
douglas_schroeder
morningstaraudio's avatar
morningstaraudio
154 posts
 
I also took shipment today of the 2604's and 827's on the Brown Dog adaptors.
A truly significant upgrade to the stock op-amps in sound. Very organic,more meat on the bone kind of tone. Punchier bottom end with a wonderful midrange.
I'll probably be offering the DAC PLUS with these pre-installed by me as it won't void the warranty that way.

Don't ask me why it took me so long to try.
Thanks to all that have contributed.
Warmest Regards,
Bill
davemm
9 posts
 
Bill. When do you think you'll be offering the DAC PLUS with pre-installed, upgraded op-amps? I've been sitting on the fence about a DAC PLUS purchase for a couple of months now. Personally have never done any op-amp rolling. Just following along on forums about tube-in, tube-out, roll op-amps, etc. Very interesting evolution of this unit since it's into. Thanks, Dave.
sibelius
256 posts
 
Well, I went off the deep end and ordered some Dexa Discrete Opamps as well to try in the U1/U2 position. They are a lot more expensive ($170 plus shipping) but I'm very curious to see if the discrete opamps are as good as people say they are. Will report back...

The EE DAC Plus is a wonderful way to upgrade your digital experience without breaking the bank. Great value and versatility for the $.
morningstaraudio's avatar
morningstaraudio
154 posts
 
Davemm,
I bought some extra 2604's and 827's and I Have the DAC's in stock so give me a call.
mfsoa
76 posts
 
Several of the above op-amps are available in 8-DIP configuration so that they will drop directly into the EE DAC without the need for Brown Dog adapters, as follows-
(check with Digikey)
OPA627 (single) can drop right into U6/7
OPA2134 and OPA2604 can drop into U1/2.

And remember that if you use the tube out only, the U6/7 op-amps aren't used so don't bother to upgrade them (pretty sure about that).

I have been using the 49990s for a while now in SS mode (original DAC) and still like them very much, but all this talk is getting me itchy again...
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