Hi,
I also thought in the direction of 'dedicated' headshell as it seems to be almost impossible to change RC values in a practical way. Btw. does anyone know of 0603 or 0805 test sockets?
Other than that there is no reason for more complexity or less simplicity than with any other circuit.
jauu
Calvin
I also thought in the direction of 'dedicated' headshell as it seems to be almost impossible to change RC values in a practical way. Btw. does anyone know of 0603 or 0805 test sockets?
Other than that there is no reason for more complexity or less simplicity than with any other circuit.
jauu
Calvin
Calvin, the Yamaha satellite amp approach only used two output leads from the headshell; ground (JFET source) and hot (JFET drain). Therefore no tonearm modifications were required.
The earlier HA-2 integrated the JFETs into a dedicated headshell (which can be used with SME-type universal bayonet sockets), while the following HA-3 delivered the JFETs inside a molded block designed to be affixed on the underside of any headshell.
http://www.sk.aitai.ne.jp/~k-chihiro/img/image.jpg
If the external amplifier section is configured to have a low-impedance cascode input (either folded or telescopic), it isn't particularly difficult to put such a distributed amplifier design together.
(I'm not sure how accurate the external amplifier input is in the above schematic, but the general design concept is correct AFAIK.)
The earlier HA-2 integrated the JFETs into a dedicated headshell (which can be used with SME-type universal bayonet sockets), while the following HA-3 delivered the JFETs inside a molded block designed to be affixed on the underside of any headshell.
http://www.sk.aitai.ne.jp/~k-chihiro/img/image.jpg
If the external amplifier section is configured to have a low-impedance cascode input (either folded or telescopic), it isn't particularly difficult to put such a distributed amplifier design together.
(I'm not sure how accurate the external amplifier input is in the above schematic, but the general design concept is correct AFAIK.)
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it does not have to be in the arm, it can be in the plinth between the cart and output cable. the tiny wires in the arm present very low capacitance (10pf or less) that shuold move the resonance point to 40khz.
compatibility is lost as the turntable and cart would output 50mV or more at 1khz.
a JFET buffer may be OK if the noise is low enough.
compatibility is lost as the turntable and cart would output 50mV or more at 1khz.
a JFET buffer may be OK if the noise is low enough.
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Hello jcarr,
Just a respectful note, the SME headshell connector is not of the bayonet type. It is a helical cam acting on one or two pins.
Sincerely,
Ralf
The example billshurv showed to us in #5 appears to be the way to go. If you've got a TT by Dual, there even ain't no need for DIYing the arm, as their headshells are easily to remove.
But is there any demand at all, given that almost any MM cartridge can cope well with load capacitances up to 500 pF?
Best regards!
But is there any demand at all, given that almost any MM cartridge can cope well with load capacitances up to 500 pF?
Best regards!
As I said, if there's any issue with it at all. There's no problem to get the tonearm cabling capacitance down to 40 to 50 pF, and even some mediocre coaxial signal cable with a capacitance of 100 pF per metre (RG 58) is easily obtainable.
Out of interest: Where are your pics related to? Are there any schematics, PCB designs etc. available?
Best regards!
Out of interest: Where are your pics related to? Are there any schematics, PCB designs etc. available?
Best regards!
To reduce weight and extra wires, why not use metal tone arm wand as wires ? Probably in two or three longitudinal sections (Signal/power ground ?) joined by small plastic section ? OR like NAD Flat tonerarm PCB with Tracks ? OR some High output Phono cartridge with builtin response of bass boost adhering to RIAA specs and then top end can be passively attenuated ?
just for fun of doing things differently ofcourse.
just for fun of doing things differently ofcourse.
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Apparently you also end up with a giant 3.2MB PNG file as your header image when it should be a 30K jpeg.
How about this to see how much difference the wires make.
1) We record music (Short piece) sample with regular interconnect (or preamp at tonearm base)
then
2) we record music with preamp extremely as near as possible to the headshell (probably on the TT Deck and beginning of 1st track) and record short piece of same music
... and compare.
1) We record music (Short piece) sample with regular interconnect (or preamp at tonearm base)
then
2) we record music with preamp extremely as near as possible to the headshell (probably on the TT Deck and beginning of 1st track) and record short piece of same music
... and compare.
a low noise 2SC1815 buffer may work well powered from the motor supply.
I have been using a 1 Meg resistor from Iphone to the phono input with cartridge attached to measure frequency response of the whole system.
The low response is higher but I am only looking at 1khz > 21khz response
I have been using a 1 Meg resistor from Iphone to the phono input with cartridge attached to measure frequency response of the whole system.
The low response is higher but I am only looking at 1khz > 21khz response
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This would mean building a cylindrical tube from up to ten different strips that are glued together at their long edges? How stable and how stiff would that be?
Best regards!
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