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Cartridge Reliability
http://www.dcaudiodiy.com/phpBB3/viewtopic.php?f=5&t=2397		 Page 1 of 2
Author:  SoundMods [ December 30th, 2024, 2:04 pm ]
Post subject:  Cartridge Reliability
Stereo cartridges pretty much rely on the life cycle of the stylus itself. A lot depends on clean records as dirt in the groves can and will act like “sandpaper” on the stylus accelerating the wear. The current opinion suggests that with clean records an elliptical stylus tracking at two gams or less should last about 1,000 to 2,000 hours play time before replacement becomes necessary. Line contact styli are known to last even beyond 2,000 hours with the belief they can even go to about 5,000 hours.

What about the rest of the cartridge? Moving coil, moving iron, and moving magnet? Unless damaged in some way by excessive input offset current from the phono stage “frying” a coil -- the cartridge should last a lifetime -or- that is if stylus replacement justifies keeping the cartridge in lieu of an upgrade.

Then there is the DS Audio optical cartridge. What with its internal electronics comprised of infrared LEDs and PIN Diode photocells – could that be the “Achilles heel” that can limit the cartridge’s life cycle?
As it turns out – NO. Current literature notes that the mean-time-before-failure (MTBF) of IR LEDs and PIN Diode photocells operated within their required operating parameters may typically run for up to 50,000-hours. So, one question that is asked; “Can I just leave my equalizer on continuously.?”

This came up because of the time it takes for the cartridge system to “come on song” with the best playback quality after turn-on. The answer is more along the lines of the equalizer build quality and whether or not the electrolytic capacitors the unit is built around are sized correctly in terms of ripple current and temperature ratings. Integrated circuits such as op-amps and IC regulators are a mixed bag because their reliability depend on the cleaning regimen before packaging during manufacturing.

Any minute quantity of photo-etching chemical left on the chip can cause premature failure from internal corrosion.
Author:  Guy [ December 31st, 2024, 6:11 pm ]
Post subject:  Re: Cartridge Reliability
That's an interesting review, SoundMods. There are a few things for me to consider!
Author:  SoundMods [ January 1st, 2025, 12:07 am ]
Post subject:  Re: Cartridge Reliability
Guy wrote:
That's an interesting review, SoundMods. There are a few things for me to consider!


The Devil is in the details. :evil:
Author:  Pelliott321 [ January 1st, 2025, 11:22 am ]
Post subject:  Re: Cartridge Reliability
What about the cantilever suspension. I thought that rubber? donut was susceptible to aging...getting had and brittle.
Author:  SoundMods [ January 1st, 2025, 11:55 am ]
Post subject:  Re: Cartridge Reliability
Pelliott321 wrote:
What about the cantilever suspension. I thought that rubber? donut was susceptible to aging...getting had and brittle.

Other than the early Grado moving-coil cartridges, I am not aware of any cartridge manufacturer using "real rubber" for their suspensions.

Materials such as Buna N -or- Neoprene -or- Silicone -or-other form of artificial elastomer is typically used that is not subject to chemical breakdown over time.
Author:  cport [ January 1st, 2025, 12:00 pm ]
Post subject:  Re: Cartridge Reliability
While this statement:

Quote:
Stereo cartridges pretty much rely on the life cycle of the stylus itself. A lot depends on clean records as dirt in the groves can and will act like “sandpaper” on the stylus accelerating the wear. The current opinion suggests that with clean records an elliptical stylus tracking at two gams or less should last about 1,000 to 2,000 hours play time before replacement becomes necessary. Line contact styli are known to last even beyond 2,000 hours with the belief they can even go to about 5,000 hours.


is 'true' (stylus "contact-point" wear is a factor in overall cartridge reliability) I think more attention needs to be paid to the role and aging of the elastomer [damper] in phono cartridges. The elastomer damper that is used in moving coils ( & MM + MI) is responsible for both the static and dynamic compliance of the cartridge and is involved in both the tracing of the groove walls (by providing enough restorative resistance to the stylus cantilever to bring it to the center again to be modulated) and the transduction, where it is what holds the coils in the area of maximum magnetic flux, with enough surface friction (via the tensioning wire) to prevent the coils from rotating. Material science has advanced in the last 40 years, but the elastomers used in cartridges are still (typically) butyl rubber derivatives, and are thus subject to oxidation-reduction and hardening - especially when exposed to alcohol - over time. To my mind, this elastomer element is the ultimate arbiter of a cartridge's “reliability.”

It is interesting to note that most “stylus retipping services” simply reuse the existing cantilever (cut short to the nib) and bond a new cantilever into the existing elastomer/coil base. Few (SoundSmith alone??) will tackle making a new coil and new elastomer bed for the cartridge.
Author:  SoundMods [ January 1st, 2025, 12:14 pm ]
Post subject:  Re: Cartridge Reliability
cport wrote:
While this statement:

Quote:
Stereo cartridges pretty much rely on the life cycle of the stylus itself. A lot depends on clean records as dirt in the groves can and will act like “sandpaper” on the stylus accelerating the wear. The current opinion suggests that with clean records an elliptical stylus tracking at two gams or less should last about 1,000 to 2,000 hours play time before replacement becomes necessary. Line contact styli are known to last even beyond 2,000 hours with the belief they can even go to about 5,000 hours.


is 'true' (stylus "contact-point" wear is a factor in overall cartridge reliability) I think more attention needs to be paid to the role and aging of the elastomer [damper] in phono cartridges. The elastomer damper that is used in moving coils ( & MM + MI) is responsible for both the static and dynamic compliance of the cartridge and is involved in both the tracing of the groove walls (by providing enough restorative resistance to the stylus cantilever to bring it to the center again to be modulated) and the transduction, where is holds the coils in the area of maximum magnetic flux, with enough surface friction (via the tensioning wire) to prevent the coils from rotating. Material science has advanced in the last 40 years, but the elastomers used in cartridges are still (typically) butyl rubber derivatives, and are thus subject to oxidation-reduction and hardening - especially when exposed to alcohol - over time. To my mind, this elastomer element is the ultimate arbiter of a cartridge's “reliability.”

It is interesting to note that most “stylus retipping services” simply reuse the existing cantilever (cut short to the nib) and bond a new cantilever into the existing elastomer/coil base. Few (SoundSmith alone??) will tackle making a new coil and new elastomer bed for the cartridge.

With a stereo cartridge suspension contained in a protected area (the cartridge body) inside a controlled environment (the average home) the elastomer expected useful life is well beyond the expected useful life as used for its original purpose in machinery or automobiles. My personal experience over 50-years + in this hobby supports that opinion.
Author:  cport [ January 2nd, 2025, 11:08 am ]
Post subject:  Re: Cartridge Reliability
Quote:
With a stereo cartridge suspension contained in a protected area (the cartridge body) inside a controlled environment (the average home) the elastomer expected useful life is well beyond the expected useful life as used for its original purpose in machinery or automobiles. My personal experience over 50-years + in this hobby supports that opinion.


Apologies, Walt - I had forgotten that this site is the forum of “declarative statements” (and no discussion -- much less general) where we need to just sit back and listen. But (for completeness) I think I will finish my thoughts and “rest” -- your personal experiences aside, the number of MC phono cartridges that do not have the “suspension contained in a protected area” is ‘staggering’ -- here are just a few pictures from lencoheaven that show 1.) Black butyl rubber is still a common elastomer 2.) The elastomer/damper is exposed -- if you add Sumiko, Lyra, Benz, and VDH to the numerous Japanese manufactures that make “open” suspensions, it is a pretty healthy number -- if the elastomer is black and slightly porous, it is likely a rubber derivative. Elastomers do age, and (as a result) change the compliance behavior over time (typically not for the better).

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Author:  SoundMods [ January 2nd, 2025, 11:43 am ]
Post subject:  Re: Cartridge Reliability
cport wrote:
Quote:
With a stereo cartridge suspension contained in a protected area (the cartridge body) inside a controlled environment (the average home) the elastomer expected useful life is well beyond the expected useful life as used for its original purpose in machinery or automobiles. My personal experience over 50-years + in this hobby supports that opinion.


Apologies, Walt - I had forgotten that this site is the forum of “declarative statements” (and no discussion -- much less general) where we need to just sit back and listen. But (for completeness) I think I will finish my thoughts and “rest” -- your personal experiences aside, the number of MC phono cartridges that do not have the “suspension contained in a protected area” is ‘staggering’ -- here are just a few pictures from lencoheaven that show 1.) Black butyl rubber is still a common elastomer 2.) The elastomer/damper is exposed -- if you add Sumiko, Lyra, Benz, and VDH to the numerous Japanese manufactures that make “open” suspensions, it is a pretty healthy number -- if the elastomer is black and slightly porous, it is likely a rubber derivative. Elastomers do age, and (as a result) change the compliance behavior over time (typically not for the better).

Yet -- I have never had a cartridge deteriorate like you claim or expect and I ever so often try an old cartridge that was relegated to second string to see how it sounds in the here and now.

One particularly -- the grand father to the Clearaudio design -- a patented Japanese cartridge -- Dianex 1000 (ca. 1978) -- that to this day is still a musical gem. For clarity -- by cartridge "protected area" it is an area that those materials typically used for suspensions are not exposed to an industrial environment where exposure to chemical processing, weather extremes, UV, or other issues that can impact documented expected useful life.

Those days are over for me -- I am forever addicted to DS Audio optical cartridges. Their suspension elastomer is blue in color -- silicon? neoprene? Who knows?

And why did you lead off your response with an adversarial snide comment? Really!? :twisted:


Author:  Stuart Polansky [ January 3rd, 2025, 4:38 pm ]
Post subject:  Re: Cartridge Reliability
This is all interesting, but the notion of paying $3000-$22,500 for a cartridge is just out of the question for many of us. While expensive equipment is the name of the game in hi-fi, and one can justify expenses for "durable" items like electronics, the reality is that cartridges do wear out, whether retipping or rebuilding is needed. I can appreciate spending tens of thousands for speakers or even for balls-to-the-wall electronics, that's a hard no for me anyway, as to cartridges.

If I have to give up on vinyl because one must have a $22,500 cartridge to really extract all the information from the grooves, then digital it is!

Stuart (the cheapster)
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