The other way is changing the components in the RIAA.
10 dB is a factor of aproxinately 3. So you have to lower the resistors by a factor of 3 and raise the value of the capacitors by a factor of 3. Gain in a transimpedance stage is :
Gm x R so lowering the resistors lowers the gain. When you lower the resistors you have to raise the capacitors acordingly or the time constants will be wrong.
Working on the emitter resistors influences Gm so raising the value of the emitter resistors lowers Gm proportionally.
10 dB is a factor of aproxinately 3. So you have to lower the resistors by a factor of 3 and raise the value of the capacitors by a factor of 3. Gain in a transimpedance stage is :
Gm x R so lowering the resistors lowers the gain. When you lower the resistors you have to raise the capacitors acordingly or the time constants will be wrong.
Working on the emitter resistors influences Gm so raising the value of the emitter resistors lowers Gm proportionally.
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In a feedback RIAA this is easier. Only one resistor. Not here.
I think the inline attenuation will work. Noise of the phono stage will be attenuated this way but you loose a bit of dynamic range. The best dynamic range you get when at maximum volume you do not get any overload. It is better to attenuate after a gain stage then before it.
I think the inline attenuation will work. Noise of the phono stage will be attenuated this way but you loose a bit of dynamic range. The best dynamic range you get when at maximum volume you do not get any overload. It is better to attenuate after a gain stage then before it.
I have been using version R2 for quite a while with no problems. Recently I have developed a hum in one channel. It is not a power supply problem. I have resoldered all the input and output signal wires. I have jiggles all the parts with no change to the hum. Any ideas would be greatly appreciated.
Regards,
Mas
Regards,
Mas
A worn out electrolytic ?
Can you measure PSU ripple with your DMM set to AC voltage?
If not then you can attach a capacitor in series with the probe and that isolates the DC component from the DMM and you then set the Vac scale starting at the highest and go down until you reach a sensible reading that is just inside the scale range.
The Vac needs to be multiplied by ~3 to arrive at a very rough approximation of the Vpp you would read on a scope.
Can you measure PSU ripple with your DMM set to AC voltage?
If not then you can attach a capacitor in series with the probe and that isolates the DC component from the DMM and you then set the Vac scale starting at the highest and go down until you reach a sensible reading that is just inside the scale range.
The Vac needs to be multiplied by ~3 to arrive at a very rough approximation of the Vpp you would read on a scope.
Hi, please take a look at the documents (link in my signature), I have used Dale RN65 resistors for the loading and a C&K rotary switch with silver contacts. Works very well.
Now, what should be a good loading IMHO depends on the cartridge and your preferences. There are people that say that the loading resistor should be 2...4 times the cartridge DC resistance, others like to use 47k for MC..... The "native" input impedance of the Paradise is around 10k, so higher load resistors will not change anything.
My recommendation would be to use a good test record (e.g. Dr. Feickert) and measure the frequency response of your setup, then tune the load resistance to linear response in the treble, and use this as a starting point for listening optimization. Just my two cents.....
have fun
alfred
Now, what should be a good loading IMHO depends on the cartridge and your preferences. There are people that say that the loading resistor should be 2...4 times the cartridge DC resistance, others like to use 47k for MC..... The "native" input impedance of the Paradise is around 10k, so higher load resistors will not change anything.
My recommendation would be to use a good test record (e.g. Dr. Feickert) and measure the frequency response of your setup, then tune the load resistance to linear response in the treble, and use this as a starting point for listening optimization. Just my two cents.....
have fun
alfred
Will this one work allright?
http://www.mouser.se/ProductDetail/...JDZNNSWJmylnlaMPozB5myi%2bzW0w66Q409NPoerPg==
http://www.mouser.se/ProductDetail/...JDZNNSWJmylnlaMPozB5myi%2bzW0w66Q409NPoerPg==