CERAMIC PHONO CARTRIDGES Pre-Amp

[Fantastic]

A ceramic pickup is a basically a capacitance and so if you don't load it with a very high impedance ( in Mega Ohms) it will have less bass. Tube input preamps are ideal for this. But you do have FET input opamps that can also be used.
My memory from a long time ago is that for this application a tube input sounds best. However I only recall seeing input impedances of around 1 Meg Ohm. You can't arbitrarily increase the input resistor of a Tube stage. Typically for small signal tubes like the ECC series you could go up to about 2.2 Meg Ohms. Of course with NFB the equivalent input Z can be made much higher.

Here you will find an opamp based one with 10Meg input impedance. However I'd bet a tube stage would sound better ! Not sure about modern FET input opamps. You will have to try them out.

Preamp Stage For Ceramic Phono Cartridge Or Violin Pickups | EEWeb Community

also check:
http://www.lencoheaven.net/forum/index.php?topic=12092.15

Read this also:
http://www.lencoheaven.net/forum/index.php?topic=12524.0

and this:
Sonotone Phonograph Cartridge History

Needles:
Phono Ceramic Cartridges by Astatic, Arista, Electro Voice & Pfanstiehl

Enjoy!

 

[Hiten]

Since stereo cartridges were developed to make them compatible with mono recordings, vertical movement of stylus determines the stereo content. If Rumble noise is out of phase, it would be logical to conclude it is due to uneven vertical movement of stylus in two channels. Some rumble sources like bearing noise, uneven belt or idler, various vibrations, transformer (if any) or any other low frequency noises which are in phase in both channel would need to be attenuated by electronic or by passive means.
Regards.

 

[IndianEars]

Guys, if you want to know / appreciate just How effective a Mono-bass Rumble cancellation filter is, Simply hit the Mono switch on your existing Pre amp or amp.

The Rumble will simply disappear.

Also if you dont hear the rumble, look at the Woofer before and after the Mono switch!

 

[IndianEars]

I think this is a great idea, especially since it is to be used for 78s. Have a queries, can you suggest a schematic idea incorporating this philosophy?

RUMBLE_FILTER - Filter_Circuit - Basic_Circuit - Circuit Diagram - SeekIC.com

Used when rumble from cheaper turntable or record extends above 100 Hz, causing disconcerting out-of-phase loud-speaker signals, Circuit is based on fact that human ear is not sensitive to directional information below about 400 Hz, making it permissible to remove stereo (L – R) signal at low...

www.seekic.com

 

[IndianEars]

Since stereo cartridges were developed to make them compatible with mono recordings, vertical movement of stylus determines the stereo content. If Rumble noise is out of phase, it would be logical to conclude it is due to uneven vertical movement of stylus in two channels. Some rumble sources like bearing noise, uneven belt or idler, various vibrations, transformer (if any) or any other low frequency noises which are in phase in both channel would need to be attenuated by electronic or by passive means.
Regards.

Many Pre amps have a Mono switch.

To quickly appreciate the efficacy of Rumble Cancellation via creating a Mono Bass, simply press the mono Button and listen ... or even look at your LF driver's cone flutter disappear...

 

[IndianEars]

A ceramic pickup is a basically a capacitance and so if you don't load it with a very high impedance ( in Mega Ohms) it will have less bass. Tube input preamps are ideal for this. But you do have FET input opamps that can also be used.

My memory from a long time ago is that for this application a tube input sounds best. However I only recall seeing input impedances of around 1 Meg Ohm. You can't arbitrarily increase the input resistor of a Tube stage. Typically for small signal tubes like the ECC series you could go up to about 2.2 Meg Ohms.

Very Nice Post, Fantastic.

There is an easy way to work around the limitations of Input Impedance of a tube amplification stage used with a ceramic cartridge.

A Ceramic cartridge (loaded by 2.2 Meg Ohms +) provides a relatively high output voltage of 300 mV to 500 mV.

This high Voltage can be used .... indirectly ... to create a much higher load on the ceramic cartridge.

As an example, consider that the input impedance of yr phono stage is 1 Meg Ohms. Insert 4 Megs ( 1Meg x 4 Nos) Series resistors between the Cartridge & the Input of the ceramic phono stage.

The effective impedance seen by the ceramic cartridge will be 5 Meg Ohms !

The Ceramic Phono stage will receive only 1/4 th the cartridge output voltage
ie 300 mV/4 = 75 mV
or 500mV/4 = 125 mV...
still plenty for the ceramic phono stage....

 

[reubensm]

feedback for this circuit, from the FM who started this thread - https://www.hifivision.com/threads/ceramic-phonostage-build.48499/page-6#post-608158