ADC QLM??
- Thread starter Yemm66
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John is of course correct. The 34 III and 36 III shared an 820-ohm body while the Mk II QLMs all had the same inductance as the XLM and VLM Mk II (~350mH) but lower resistance (~440 ohms vs. 620 ohms).
Nerd Note: the "QLM Mk I"s weren't QLMs at all, but Qs: Q32, Q36, Q321, Q361...
But what you have there is a stylusless Japan-made QLM 30 Mk III. I know this because of the distinctive way the terminal pins on the back emerge from holes in the terminal block.
The body is nearly identical electrically to the original XLM of 1972, and the stylus that came with it was the cheapest ADC/BSR ever made. Not that it was horrible, but you really wanted something a bit better to get an idea of what ADC was all about.
It will be difficult, though not impossible, to find a top-line original stylus for that body, should you even want to.
Nerd Note: the "QLM Mk I"s weren't QLMs at all, but Qs: Q32, Q36, Q321, Q361...
But what you have there is a stylusless Japan-made QLM 30 Mk III. I know this because of the distinctive way the terminal pins on the back emerge from holes in the terminal block.
The body is nearly identical electrically to the original XLM of 1972, and the stylus that came with it was the cheapest ADC/BSR ever made. Not that it was horrible, but you really wanted something a bit better to get an idea of what ADC was all about.
It will be difficult, though not impossible, to find a top-line original stylus for that body, should you even want to.
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Yemm66
Active Member
I measured the pins and got .422 and .431 ohms. Does that narrow it down any further?
Yemm66
Active Member
Hi John. Thanks for the info. I measured .422 and .431 ohms on the pins. Does that give you any further distinction?
John, you were correct in the essentials. The Mk III era showed the breaking away of the QLM 34 and 36 from the lesser QLMs-- measurements show that the 34 III and 36 III did indeed use the same 820-ohm body as the concurrent XLMs, VLMs and ZLMs.
By the way, Mk II-era QLMs do have resistance in the 440-ohm region, while the Mk II XLM and VLM were spec'd at 625 ohms. This difference has virtually zero effect on the sound.
The wellbeloved 4108-DET from tVOM [UPDATE: no longer made in Japan] ... I think most people would judge it to sound weak and bassless in a Mk I or II body (even though it's the treble that's been boosted, making the bass weak by comparison). I want to recommend it but can't. If our OP does want to get his ADC on, he would be well advised to seek out a Mk III body, which could be a QLM 34 or 36 Mk III; those tend to go cheap because people firmly believe QLM bodies make all styli sound QLMish, and say so loudly.
By the way, Mk II-era QLMs do have resistance in the 440-ohm region, while the Mk II XLM and VLM were spec'd at 625 ohms. This difference has virtually zero effect on the sound.
The wellbeloved 4108-DET from tVOM [UPDATE: no longer made in Japan] ... I think most people would judge it to sound weak and bassless in a Mk I or II body (even though it's the treble that's been boosted, making the bass weak by comparison). I want to recommend it but can't. If our OP does want to get his ADC on, he would be well advised to seek out a Mk III body, which could be a QLM 34 or 36 Mk III; those tend to go cheap because people firmly believe QLM bodies make all styli sound QLMish, and say so loudly.
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Only avoid the lower QLMs, anything below 33. They may be labeled "Mk III", but they don't use the high-inductance body used by the QLM 34 and 36 Mk IIIs, or, for that matter, the XLM Mk IIIs or the ZLM models-- the real Mk IIIs, at least in my mind.
Oh, and despite the name, the body for the "XLM Mk II Improved" is really a Mk III. Don't ask why [marketing].
If an "Integra" integrated-headshell model shows up and it fits your tonearm, don't reject it out of hand.
Oh, and despite the name, the body for the "XLM Mk II Improved" is really a Mk III. Don't ask why [marketing].
If an "Integra" integrated-headshell model shows up and it fits your tonearm, don't reject it out of hand.
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JimmyEJames
Super Member
I had ADC motor once and gave away with small clutch of other cartridges accumulated from various tables
Only marking was ADC and below that 10 no other letters suffixes nothing else
Was this mistake?
JJ
Only marking was ADC and below that 10 no other letters suffixes nothing else
Was this mistake?
JJ
You can try it on your 30 body, but it will sound better on a "real" Mk III body. By better I mean not only will the response curve be flatter, but the cartridge's output will increase as well. The 4108-DET John asked about earlier is also voiced for a "real" Mk III body.
Yemm66
Active Member
Thank you John!
High-inductance [inductance is abbreviated "L"] ADC body shopping tip: Often you simply have to know/guess which offerings are likely to include a high-L body. For example, there's a JVC headshell currently being auctioned with an ADC Series II cartridge. The Series series is all high-L, having appeared after the introduction of the model lineup headed by the ZLM and the XLM Mk III. There will be other auctions where the model name will at first be completely opaque. When you see something like this, best to ask here on AK what the heck it is.
Organdonorparts.com [now closed] sometimes has used ADC bodies (with iffy styli, so you're basically buying the body) for cheap. eBay seller vinyl_reclamation very often has used ADC bodies, though in both cases you may have to ask for a measurement.
Organdonorparts.com [now closed] sometimes has used ADC bodies (with iffy styli, so you're basically buying the body) for cheap. eBay seller vinyl_reclamation very often has used ADC bodies, though in both cases you may have to ask for a measurement.
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msg1975
Active Member
Someone has it for sale locally with a headshell for $40. I have a PSX-40 and love it (not even 100 hrs on it). So I thought this might be a great spare. Worth $40?[/QUOTE]
The problem with the older ADC bodies is the difficulty of finding the good older styli that will give a flat response curve in those bodies. The best would be the XLM Mk II (not Improved) or one of the better Integra styli (RXM-III or RXT-III or IV). If you're used to the nice flat response curve you're getting from your PSX-40 (a big favorite of mine and many others here on AK), you'll want something comparable, and a generic conical isn't likely to give it to you. $40? I'd pass.
