1DIFFQC amplifier

The 1DIFFQC Amplifier
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Hi Guys

Integrated Darlington packages are only ever used when cost overrides performance and reliability - so only for budget amps like guitar amps and cheapo stereos.

Use a discrete Darlington circuit and cross-connect the bases of the output BJTs with a single R for faster response. Yes, it is five parts instead of two but it is more reliable and performs better. The bias reg should be affixed to the drivers on their own little heatsink. Only the outputs should be on the main heat sink, otherwise you run into problems similar to having the integrated Darlingtons.

For outputs use TO-3P or TO-247 devices. For drivers use TO-220 types.

Have fun
 
Thank you for the input Struth. This research amplifier will most likely allow us to explore more about our perceptions about darlingtons, PSRR, quasi complementary, T.H.D. and a few other parameters.

There are a group of audio researchers working hard at it right now (they are putting themselves out there for us) i.e. WSJ, Kindhornman, Evette, Dagwood and many more.

As we await for feedback from them. You can read a surprising result here : PauloPT 1DIFFQC

There has to be a balance between what the meters measure and what the ears perceive. Sound perception and its dissonance with measurements is a broad area of research.
 
Harrison,
I just caught this thread. I am about to stuff all the capacitors, all the resistors and diodes are in and I see that you are talking about changing the output transistors. What has you going in this direction, is this just another possibility or has something changed in your thinking?
I'll have to look and see what is going on.

Steven
 
Okay Harrison,
Is the reason that these people want to use a different device because of noise differences or is there just some preferences for one output device over another? I haven't compared the BOM to the original yet to see what changes you have posted. Is it only the output devices or are there also other changes to optimize these output transistors? I am building the amplifier with standoffs so I could potentially change the output devices without have to De-solder the devices. I will watch and see what is going on closely.

Steven
 
Hope someone has something for us today ;) . There are over 60 boards out there. Kindly share with us your research findings. Remember the first target is 30,000 results;) . A journey starts with the first step. Your feedback counts. We have individual tastes in music and our ears are unique. Is there a solution that pleases all ears and tastes ?
 
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Hello Everybody,, A quick update 1-on the first channel that I builded I used TIP142 transistors I enjoyed the sound very much my supply was at 37-+ volts. Then I try Changing my outputs and I used another suppy 45-+ The outputs are now MJH6284
Now this amp has come alive The bass takes you to the center of the earth and the highs put you on cloud 9. You,ll end up listening to your whole collection of music again.
 
Hello Everybody,, A quick update 1-on the first channel that I builded I used TIP142 transistors I enjoyed the sound very much my supply was at 37-+ volts. Then I try Changing my outputs and I used another suppy 45-+ The outputs are now MJH6284
Now this amp has come alive The bass takes you to the center of the earth and the highs put you on cloud 9. You,ll end up listening to your whole collection of music again.

If You built anything in life Please put this amp on top of your list. Evette

Thank you Evette for contributing to the state of the art. :cheers: . I am humbled. Thank you for your quick build and sharing with us.