I have a Classe Twenty five which use an input op amp buffer. The buffer could bridge the stereo amp to do a mono amp. If I don't need to use the amp in mono, Could it be a good thing to bypass this buffer stage ? I tried it and the amp was too bright sounding. Did someone tried something with these amps ? Thanks
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The difference in the R101-R012 and R103-R104 networks are to compensate between pro (balanced) and consumer (unbalanced) sources. It seems the main amps are of a balanced input category (+L -L and +R -R)
IC101A & B are behind the regular/bridge selector. Depending on the circuit of the main amp, these buffers could be omitted in theory, but other unwanted surprises may occur.
A picture of the main stage will indicate so.
What's the name of the buffers?
IC101A & B are behind the regular/bridge selector. Depending on the circuit of the main amp, these buffers could be omitted in theory, but other unwanted surprises may occur.
A picture of the main stage will indicate so.
What's the name of the buffers?
By all means remove those horrible Op Amps (ugh!!!) and replace them with wirelinks across pins1-3 and 5-7 .
The old saying compares perfect Amplifiers to "wires with gain" but since here gain is 1 so "no gain" they are clearly doing nothing.
So by definition a REAL wire with no gain will always be better than a FAKE wire with no gain, what do you need them for? 😕
Real wire will be flat 0 Hz to 300 MHz within 0.00000000001dB while those Op Amps will start *dying* in an ugly way above, say, 3 MHz; 10MHz best case ... who needs that?
I see you bought a $2000 amplifier and slowly but surely are turning it into a $50 one by removing all useless components added by designer.
What was he thinking? 😱
Buffers are used to make sure if there's a low impedance needed for the next stage.
Hence output semi's in common emitter config to drive a loudspeakers.
The amplification of buffers is almost 1, but the 'wire'-quality'is not what is needed here.
Wires don't lower impedences.
Otherwise we can omit output semi's altogether.
Hence output semi's in common emitter config to drive a loudspeakers.
The amplification of buffers is almost 1, but the 'wire'-quality'is not what is needed here.
Wires don't lower impedences.
Otherwise we can omit output semi's altogether.
😀
Marketing tells us that op amps and capacitors are bad for sound.
Marketers always know more than product designers, right? Let's get our technical advice from audio magazines and ignore the dogma spewed by the design engineers.
The Op amps used have erased numbers by Classé. Here is the input stage of the amp.
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Yes, that's the same amp from your other post.
Do not omit the coupling caps; they're part of the ampdesign.
Depending on the source (pro/consumer) you can give it a try with the unbalanced input.
There's a divider of 1k/1k and some stry cap to make a (random) hf filter.
You could try to change that into a regular 100ohm/100p filter.
But don't blame me if the amp transforms into a nuclear meltdown.
There is more schematic between the posted pictures (+L -L ----> +VE -VE).
What's there dressing the signal and amp?
Do not omit the coupling caps; they're part of the ampdesign.
Depending on the source (pro/consumer) you can give it a try with the unbalanced input.
There's a divider of 1k/1k and some stry cap to make a (random) hf filter.
You could try to change that into a regular 100ohm/100p filter.
But don't blame me if the amp transforms into a nuclear meltdown.
There is more schematic between the posted pictures (+L -L ----> +VE -VE).
What's there dressing the signal and amp?
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