The new circuit of the DLH Super Buffer is in the Powerpoint file. For those who can not open it, here is the new schematic.
As you can see, the resistance of 390 ohms has been eliminated by the strategic relocation of the trimpot for the adjustment of bias. The number of components and the possibility of faults are reduced.
is this version valid only for super buffer or works for the gain version too? (with feedback resistors)
is it possible to vary the gain of the DLH to 3 or 6dB? will this impact sound?
Can I use BC337-40 instead of the BC550?
And BC559 instead of BC560?
If I understood correctly your statement:
It is highly recommended that the hFE value of the BC550 is not less than 50% of the hFE value of the BC560. If the hFE value of the BC550 exceeds the hFE value of the BC560, there is no problem
If hFE of bc560 is 400 the hFE of BC550 should be at least 200?
Can I use BC337-40 instead of the BC550?
And BC559 instead of BC560?
If I understood correctly your statement:
It is highly recommended that the hFE value of the BC550 is not less than 50% of the hFE value of the BC560. If the hFE value of the BC550 exceeds the hFE value of the BC560, there is no problem
If hFE of bc560 is 400 the hFE of BC550 should be at least 200?
I think there would be no major drawbacks in using the IRFP240 instead of the first suggested one. I think that there might even be some small advantage due to the lower capacitances involved. It is a matter of simulating it and analyzing what may happen. If something has to be modified, I think it should be very little of the original.
I believe that the DLH could achieve lower total distortions than the others mentioned and with little complex profiles.
Anyway, it is not the amplifier alone that accomplishes this very thing. Do not forget about the speakers and the listening environment, which make the biggest difference.
Changes in the values and position of the components for bias polarization in the DLH Super Buffer (DLH SB) can also be implemented in the DLH (with voltage gain).
It might be possible to increase the gain. Quite possibly, both Johnson's noise and total distortion will increase, too. It would be necessary to analyze if they are still acceptable.
About the changes in the transistors and the relationship between their hFE, I think it would be possible without major detriments in the final parameters of quality.
Thanks I do not have the equipment or knowledge to simulate it and analyze. I am better off then to look for IRFP150 then rather than use IRFP240.
Would it be possible to increase output power by raising the supply voltage and/or doubling the output devices?
How much would performance suffer from raising the supply voltage to say +/- 30V?
I tried to simulate the circuit in Multisim 13.0, but can’t get distortion analyses running (AC analyses is doing fine).
Peter
How much would performance suffer from raising the supply voltage to say +/- 30V?
I tried to simulate the circuit in Multisim 13.0, but can’t get distortion analyses running (AC analyses is doing fine).
Peter