Ceramic Phonostage

[reubensm]

Dear all, after one of my old threads on a record changer restoration came up, I started receiving a few requests for details related to ceramic phonostages. Yes I have tried a few of these and found this one to be my favourite and the best of all. Here is the circuit just in case you are on the look out for it:



Assembly notes:

• Use only metal cap BC109s for enhanced performance
• Ensure wiring of both channels do not inter-cross if mounting both on the same bread board
• Watch out for dry solder
• If using a PSU, ensure suitable filtering and regulation for optimal results
• If mounting in a separate cabinet, prefer a metal box with suitable grounding, avoid grounding loops

An example of one which I built (image courtesy FM Record Player):



Performance notes: Why did I finally zero in on this circuit despite trying many others, with FETs, OP Amps, etc? The answer lies in the bass response and overall quality, especially when used with an idler driver turntable. Also the gain is not too high and hence, has worked well with all the NAD amplifiers that I've used it with. The cartridges that I've used with this phonostage are (1) EEI CS2000 and (2) Sonotone 8T.

If you want to avoid the trouble of having to build one, you can even try out a passive network but with some loss of gain. I have always preferred the active version. Here is an example of a passive eq circuit (courtesy: sonotone ceramic cartridge brochure). The circuit on the left is for a regular aux input and the circuit on the right is for connecting a ceramic cart to a magnetic cart input.

 

[reubensm]

Received a few queries enquiring about ceramic cartridges, specifically for playing old worn LPs, 45s and 78s so thought I'll share some info:

There are Chinese ceramic cartridges readily available (the red plastic types) and sound ok but I've never come down to trusting its stylus on my records. The HMV stereo ceramic carts available in India are nice and EEI CS2000 of course was perhaps the best sounding and most popular of the EEI stereo ceramics. Another good model is the EEI CS2040 stereo cartridge which was allegedly rebadged and sold by Garrard as the Garrard KS40 featuring in portable Garrard record players and changers of the late 1960s and 1970s. The HMV and EEI cartridges can be commonly found in old radio shops, with dealers of vintage radios and record players, on olx, etc.

There are unfortunately a few myths associated with ceramic cartridges, the most common ones being: (1) they damage records and (2) they produce very poor quality sound. It is very important to understand vinyl culture and the evolution of record playing equipment of those times, to understand where these myths came from. Firstly some of the first cartridge types for playing 78s used gramophone steel pins with very heavy tracking. When vinyl microgroove records came on the scene, it was common to find an advisory on the record cover alerting the user to use light weight pickups. Also there was little awareness about stylus wear, etc when it came to regular users. Most ceramic cartridge styli in those times in India were Sapphire based which meant less life and hence, it was common to come across users playing records with worn styli. There was also little awareness about VTF. I recollect from my child hood days, our aunt at this habit of placing a 50 paisa coin on the head-shell if "the record did not sound clear". A lot of records previously owned in India by users in this segment come with some degree of groove damage. Then there is the opinion about quality. If a ceramic cartridge requires a high impedance input with a suitable EQ for it to sound good. Many ignore this fact and hence end up with a screechy and harsh sounding ceramic cartridge.

From my experience, the Sonotone 8TA, 19T2, 21TR and 22TR are great sounding ceramic cartridge. If you are really interested in ceramics and hope to acquire a really good one, look out for one of these. NoS versions of these come up on eBay every now and then but prices have gone up these days. More info on Sonotone cartridges is available here.

But by far, the best stereo ceramic cart which i have come across is the Philips GP390 with diamond needle. These are not easy to find and I was lucky to be gifted one. There are some unique aspects to this one, firstly it has an inbuilt network, so is a low output cart and cannot be connected to an amplifier without a proper phono stage (even for testing purposes). Secondly the stylus consists of just the cantilever and diamond tip. Thus It is not easy to replace the stylus but if you can find one in good condition, this is the ceramic cartridge to have. But sound wise, it is by far the best. Here are some pictures:




Note: all pictures are stock photographs, the last 2 pictures are of the replacement stylus and inbuilt EQ network

So why use these after all. Per my experience, while playing older records I have noticed that ceramic cartridges with about 5-6 g VTS track well and tend to have better engagement with the record groove. As they are not mighty sensitive, I have noticed that surface noise, ticks and pops tend not to be over exaggerated. Also one can save the wear on the stylus of one's expensive cartridge collection and still enjoy old records. When used with a good phono preamp, they can be made to sound very listenable. The debate of Ceramic vs Magnetic (MM) can be summed up in one sentence perhaps - Ceramic, plays everything with a simple phonostage, loud and clear, with kicking bass but marginally little thin across the mid ranges, Magnetics are all rounders with better frequency response overall but heavily dependent on the record condition, tonearm tracking, phono stage and of course, the stylus itself.

An example of the cartridge in action:

Disclaimer: all opinions are based on the experiences of the author
Notes: Based on my experience, all ceramic cartridges do not sound that great when using simple passive load balancing. It is always preferable to use a single or two stage phono preamplifier with EQ.

 

[General_sound]

Entirely agree with you. I have used atleast three GP 390 on my Philips GA 242 and still have the carts with me. Sadly they are not functional. Philips made an outboard phono stage specifically for GP 390 with settings Mag-GP390-Flat. Somehow sounded good with old Bollywood LPs. Thanks for the memories,R.

 

[reubensm]

A good read on ceramic pickup equalization