Philips GP390 Ceramic cartridge NOS 1970s

[Audioflyer]

Hello Sharif.

How are you? I hope fine!

Very interesting this review about Philips GP390 cartridge! Yesterday I installed a NOS Philips GP380, that has that same specifications of GP390 but built on P-mount body.
I’m very impressed about the GP380, it’s very, very detailed even installed on a simple and automatic table like my Philips GA160. I think that this fun table but I know that it has many mechanical limitations but, I don’t know the magic that the GP380 does, it sounds very very good!
The only issue is the Bass is a little lean. I read your post about the EQ Box Bass Boost and I’m very interested on this box.
I do not have much skill with electronics, but I will try to build one, if you can help me with a doubt, I will be very grateful.
To have a good result as you mentioned, which brand of components should I buy to try build the circuit?
Many thanks per your attention.

Attachment 17923

Best regards from Brazil.

Flavio.

C1 33nF Polypropylene capacitor
C2 C3 1.0uF Polypropylene capacitor

All the resistor are 0.25 watt 1% metal film or smd 1206 or 0603 thin film series.

I hope that helps.

Sharif.

[Audioflyer]

From memory,a ceramic cartridge, input on an amplifier needs to have a very high impedance, otherwise bass is curtailed.

Just had a quick search found this:

http://www.keith-snook.info/wireless...ualisation.pdf

It's not you standard ceramic cartridge it was design to be used with a MM riaa stage.

The information that I've found out about it, is that it has output of about 8mV across the ceramic elements.
This then feed a resistor network built into the cartridge to give an output of (1 kHz): 1mV/cm/s

I've seen the Wireless-World 1971 article, the adjust for the ceramic cartidge is done using the tone balance network on the preamp's input.

Sharif.

[jmrecchia]

Hello Sharif.

Many thanks per your attention! I will buy the components and try to build the EQ Box.

Best regards from Brazil.

Flavio
jmrecchia@gmail.com

C1 33nF Polypropylene capacitor
C2 C3 1.0uF Polypropylene capacitor

All the resistor are 0.25 watt 1% metal film or smd 1206 or 0603 thin film series.

I hope that helps.

Sharif.

[Duemaas]

I don't know if any of you have been looking at the stylus in a micriscope or a magnifying glass?
The stylus isn't a bonded stylus, but a nude diamond in gem stone quality.(It's also so big it could be used as gem stone.)
I could also read it in the brochure, that came with the NOS cartridge, I bought for £11.

Regards Jakob

[Duemaas]

Audioflyer, you said the stylus on Philips GP390 couldn't be changed.
According to the brochure it isn't true, the replacement stylus number is 4822 251 30009. I suppose
you have to carefully unscrew the on under the cantilever to change it.

Best regards Jakob.

[Mike2000]

The instructions for replacing the stylus are available on vinylengine https://www.vinylengine.com/library/...s/gp-233.shtml

Whilst listed under GP233, this is the same stylus used by the GP380 & GP390

[Audioflyer]

I manage to find a genuine replacement stylus for the GP390 which comes with a tool to hold the ceramic elements in place while you remove the stylus.

I've since spoken to ESCC about removing the stylus and their advice was not to try and remove it, as the ceramic elements are bonded to stylus and due to the age of the cartridge it would be easily damaged.

One of my current GP390 is with ESCC having a paratrace stylus fitted so I'm looking forward to hearing it hopefully it will be back by next week!

I'll be taking a GP390 with or without the paratrace stylus to the Scalford show and if you never heard how good a ceramic cartridge sounds you should come and have a listen.

Sharif.

[narabdela]

If you never heard how good a ceramic cartridge sounds come and have a listen.

Sharif.

I'd second that. Prepare to be amazed at how good this supposedly redundant technology sounds.

[Mike2000]

One of my current GP390 is with ESCC having a paratrace stylus fitted so I'm looking forward to hearing it hopefully it will be back by next week!

I'll be taking a GP390 with or without the paratrace stylus to the Scalford show and if you never heard how good a ceramic cartridge sounds you should come and have a listen.

Sharif.

I hope you have the GP390 paratrace at Scalford - that is something I would like hear!

[Audioflyer]

My Philips GP 390 finally arrived back from 'Expert Stylus Cartridge Company' this is now the first ceramic cartridge which has a para-trace stylus fitted.

I had hope to take this to Scalford Hall Wigwam show, I'm not sure what to expect but I do have high hopes for it.

Sharif.