sbulack
Headphoneus Supremus
- Joined
- Dec 12, 2003
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I've read two seemingly different statements about the Class A Biasing in the 2007 Micro (not Ultra) Amp.
On the webpage describing the 2007 Micro Amp (Electronics) it says:
"The excellent Texas Instruments OPA134 op-amp is used throughout, and all resistors are of truly extraordinary audio quality; Rest assured, all Micro Amp stages are fully biased into true 'Class-A' audio performance!"
In the Manual describing the 2007 Micro (and Ultra Micro) Amps it says:
"The major difference between the Micro Amp and Ultra Micro Amp is that the Ultra Micro Amp uses TI 627s instead of TI 134s, and that all the op-amps are biased into class-A operation with JFET CCDs. The result is improved musical detail resolution, quicker dynamics, more precise tonal presentation, and better soundstage imaging." (And the picture of the PCB's of the two amps encircles the JFET CCDs on the image of the Ultra Micro Amp, with no such circles on the Micro Amp image.)
Also in the Manual describing the features common to Micro and Ultra Micro Amps is says:
"Discrete emitter follower ouput stage, biased into class A operation (the Diamond buffer)"
It would appear from the manual that only the output stage of the Micro Amp is biased into Class A operation, and not the stage in which the TI 134 opamps are used.
Is the statement on the webpage that all stages of the Micro Amp are fully biased into Class A a "copy and paste" error from material intended only for the Ultra Micro Amp page?
My asking this question is not academic. I've placed an order for the Micro Amp and I'd like to know the extent to which its stages are biased into Class A operation.
Thanks very much for any information you can provide to clear this up for me.
On the webpage describing the 2007 Micro Amp (Electronics) it says:
"The excellent Texas Instruments OPA134 op-amp is used throughout, and all resistors are of truly extraordinary audio quality; Rest assured, all Micro Amp stages are fully biased into true 'Class-A' audio performance!"
In the Manual describing the 2007 Micro (and Ultra Micro) Amps it says:
"The major difference between the Micro Amp and Ultra Micro Amp is that the Ultra Micro Amp uses TI 627s instead of TI 134s, and that all the op-amps are biased into class-A operation with JFET CCDs. The result is improved musical detail resolution, quicker dynamics, more precise tonal presentation, and better soundstage imaging." (And the picture of the PCB's of the two amps encircles the JFET CCDs on the image of the Ultra Micro Amp, with no such circles on the Micro Amp image.)
Also in the Manual describing the features common to Micro and Ultra Micro Amps is says:
"Discrete emitter follower ouput stage, biased into class A operation (the Diamond buffer)"
It would appear from the manual that only the output stage of the Micro Amp is biased into Class A operation, and not the stage in which the TI 134 opamps are used.
Is the statement on the webpage that all stages of the Micro Amp are fully biased into Class A a "copy and paste" error from material intended only for the Ultra Micro Amp page?
My asking this question is not academic. I've placed an order for the Micro Amp and I'd like to know the extent to which its stages are biased into Class A operation.
Thanks very much for any information you can provide to clear this up for me.