Cartridge choices for a low mass tonearm

[DENNYDOG]

While I've been working on getting my PL-61/ PA-1000 finished I have been trying to figure out what the best cartridge/ arm combination would be. I looked all over and couldn't find any published mass specs for the tonearm. It is low mass which means I would need a high compliance cartridge. Without knowing the exact mass I am at a loss here. I found some calculators but don't want to guess at the value of the arm to figure out the resonant frequency. I do have the original carbon fiber hs along with a magnesium hs from a PL-630 that I can use.

I am looking to spend around $300 on cartridge. I have already bought a new Denon DL-160 (based on all the reviews I have read)that I found at a very good price and couldn't pass it up. Now after a little research it looks like it might not be the best match compliance wise. I wanted to get an MC but from what I have found most are low compliance. Luckily this is probably the highest one I have seen at 14.

It looks like the Ortofon 2M bronze might be a better match with a compliance at 22. This cartridge is right at the max for what I would like to spend. This is a MM cartridge but that wouldn't bother me if it matches up better.

Any thoughts?

Thanks, Denny

 

[thedelihaus]

I run an Ortophon LM 30 on my low mass carbon armed ADC LMF-1. The OM 30 is supposedly nicer than the LM series, being a newer generation.

This arm also would work well with an ADC XLM and supposedly the Shure V15.


Are you going new exclusively?

 

[hakaplan]

Almost all s-arms are medium to high mass and the PA-1000 is no exception. Low mass arms are typically skinny straight arms. So a medium to low compliance cartridge is what you want ideally. Use tracking force as a guide--medium to high TF. Now many folks successfully use high compliance carts with s-arms, but if spending a lot of money I'd concentrate on something more ideal. So the Ortofon 2M Red or Blue would mate better. The DL-160 should be fine.

 

[ChairSpud]

The OM series being more compliant than the 2M might be a better match, you may want to look at the OM30.

Too bad about the Denon, they do sound very nice for the money. FWIW William Thaaker did tell me in an email that they are more compliant than their spec indicates.

Edit:
Dang you guys are fast!

 

[thedelihaus]

Denny, after taking a look, with your ar. I suspect the Denon to be a nice match.

 

[DENNYDOG]

Thanks guys. I was under the assumption that it was a low mass arm because of the carbon fiber. Howard told me the Denon would be fine in a couple PM's but wanted to see what others thought.

It would be nice to know or try and figure out what the mass actually is so I can plug in some numbers into the calculators. I did a search but found that just weighing the end of the tonearm without the weight on the arm doesn't give an accurate measurement. I guess Pioneer never published the specs as they didn't buy into the resonant frequency talk.

Anyone care to take a guess as to what the mass might be? :scratch2:

 

[thedelihaus]

Probably a medium/medium low mass arm- not low mass, not ultra low mass.

I have a medium/medium low mass arm and indeed the Denon is fantastic with it.

 

[DENNYDOG]

Probably a medium/medium low mass arm- not low mass, not ultra low mass.

I have a medium/medium low mass arm and indeed the Denon is fantastic with it.

Then it sounds like my search is over. It still would be nice to figure out the mass to see what the resonant frequency would be.

 

[ChairSpud]

A very nice looking arm and with a usable cartridge weight of 4 to 15G definitely in the medium mass category just as Howard said. Found these in an old thread in case you're interested.

 

[DENNYDOG]

Ok I did some number crunching concerning the arm and the Denon DL-160. I used the resonant frequency formula from the Analog Depot site. I don't know the exact weight of the fasteners so I used the same weight they did which shouldn't be too far off.

Cartridge weight: 4.8 grams
Fastener weight: .5 grams
Compliance: 14x10-6cm/dyne from the Needle Doctor

This is what I came up with listing the effective mass first followed by the resulting resonant frequency.

EM 8 grams/ RF= 11.65

EM 11 grams/ RF= 10.5

EM 15 grams/ RF= 9.43

EM 18 grams/ RF= 8.8

EM 20 grams/ RF= 8.4

EM 22 grams/ RF= 8.13

I would think the arm would fall somewhere in between the weights listed. It says the ideal frequency range is 8 to 12 hz. From what I can tell the Denon should be an excellent match.

 

[hakaplan]

If 14CU is an accurate compliance then yes, it would be fine according to the formula. Problem is that often compliance specs are for 100Hz rather than 10Hz. I'm dubious about these numbers and hence the results when plugging them into the formula. But putting all that aside, the DL-160 should still be fine.

The carbon fiber shaves perhaps a gram or so off the mass so it's not going to be earth shattering in that respect.

A quick and dirty arm mass measurement:

You need a digital pocket scale, cheap on ebay or harbor freight. Remove all weights from the tonearm. Keep the cartridge and headshell mounted, but remove the stylus. Place the scale weight surface even with a record on the platter. Place the arm on the scale so the front of the cartridge is on the weighing surface. Note the readout. Subtract the weight of the cartridge (without stylus) from that reading and that's your arm mass, give or take a gram. And that's close enough. Remember that arm mass includes the headshell, so that using lighter headshells will lower arm mass and enable you to use higher compliance cartridges. This is why I recommend against heavy, fancy headshells like the Sumiko, and prefer cheap, light headshells like the generic, vintage grid design.

 

[DENNYDOG]

If 14CU is an accurate compliance then yes, it would be fine according to the formula. Problem is that often compliance specs are for 100Hz rather than 10Hz. I'm dubious about these numbers and hence the results when plugging them into the formula.

How do you really know for sure what Hz the manufacture is stating the compliance for? To tell you the truth I'm not even sure which one the formula should use. The 100Hz or 10Hz. If that is the case (and you really don't know for sure) why do they even publish the compliance spec if they don't state where it is measured at?

I thought I was getting a handle on this and another monkey wrench is thrown in. :tears: I'm not blaming you Howard. You have been a great help but it shows once again that a lot of the specs manufacturers list are worthless unless they are measured and interpreted the same way.