Denon DP-35F and the Denon DL-103 Cartridge

Dear hifi enthusiasts,
I joined this forum recently because I dusted off my audio kit after ten years of barely using it. Much to my surprise everything still worked fine. I was again captivated by the sound of my LP's and decided that I did not want to risk damaging them using the 30 year old Denon DL-301 that saw a lot of use in the past.

So I discussed my options with my local hifi specialist. He adviced me to buy a Rega RP-3 with an Ortofon MC Bronze. A combination that will set me back around € 1300. Too much for me since I have no clue at this moment in time if I am going to use a new turntable enough to justify the investment.

So I decided to only buy a new cartridge in my current Denon DP-35f turntable. The requirement for the cartridge being: good sound, maximum € 400, low output MC (because my Naim Nait 3 has an MC phono stage) and matching both my current Denon turntable as well as having a future upgrade path. After a lot of investigation I decided to go for an experiment: I am going to fit a Denon DL-103 into my DP-35f!

The intention of this post is to document the findings from this experiment for the rest of the world. I want to do that because there is a lot of discussion on the net on the DL-103. They say it sounds great but needs a 'heavy' tone arm because of its 'very low' compliance and a 'special' phono stage due to its 'lower than average' output. I read a lot about cartridges, tonearms and turntables in general and the DL-103 in particular. From that I am not sure that all I read is consistent with the facts as they are and conventional wisdom. So that is why I want to share my findings with the rest of the world while trying to be as objective as possible.

Let me start with the as-is situation and the basics:
My Denon DP-35f turntable has a Denon DL-301 (Mk. 1) cartridge. This is mounted 30 years ago by my dealer, extensively used, regularly cleaned but alignment wise never looked at since. The tonearm fitted with the turntable is an electronically controlled 'servotracer' arm with electronic damping. I have not been able to find any information on its effective mass but assume it is a low mass arm (<10 gr, maybe even <8 gr). The arm height cannot be changed. This limits the cartridge choice and is one of the reason's for choosing the DL-103. The DL-301 has a rated compliance of 13 (at 100 Hz) and a mass of 4,5 gr.. It is currently mounted with a small shim plate. The cartridge-headshell combination currently weighs 10 gr.. In a direct comparison with my Arcam CD player of equal price the turntable was sounding far better on all aspects playing the same music material. This was to my ears but also to the ears of my friend with high end hifi at home.

The DL-103 has a rated compliance of 5 (at 100 Hz) and a mass of 9 gr.. One of the (multiple) criteria for a good cartridge-tonearm match is the resonance frequency for the particular combination. Conventional wisdom has it that the resonance frequency of the cartridge-tonearm combination should be between 8 and 14 Hz. A more conservative view on the limits has it that the resonance frequency should be between 9 and 11 Hz. For a certain cartridge-tonearm combination the actual resonance frequency can be determined with a test record.
It can also be reliably predicted with this formula: rf = 159 / sqrt ((eff. mass + cart weight + fastener weight) * (compliance)). This formula has the effective tonearm mass as one of its arguments. And for me that is an unknown since Denon did not specify it.
Another unknown is the DL-103's exact cartridge compliance. The above formula's compliance argument needs a compliance value at 10 Hz but Denon only specifies it at 100 Hz. A rule of thumb is that the compliance value at 10 Hz is 1.5 to 2 times the compliance value at 100 Hz. This means that the DL-103 compliance at 10 Hz may be 7.5 to 10. But as this is a rule of thumb we cannot be sure until we measured it (using a mounted cartridge and a test record).
To be able to reliably predict the match between my DP-35f and the DL-103 (on resonance frequency) we first need to know the effective arm mass. And since I suspect that the arm mass is low and cartridge compliance lower than average this may mean that the new combination will not have its resonance frequency between the desired limits.

So the first step in my quest for a new cartridge is to check the cartridge alignment of my current cartridge and play a test record with it to determine its current, actual resonance frequency. From that I can then calculate the effective arm mass for my DP-35f with DL-301. Once I know that, I can calculate the total effective arm mass for the DP-35f with DL-103 (the DL-103 is heavier than the DL-301 and will therefore increase the total effective arm mass) and make some calculations on the predicted resonance frequency. This will allow me to (tentatively) predict the cartridge-tonearm match before buying the DL-103 cartridge.

And that is what I will do in the next few weeks. I will share my results once I have them. In the meantime all comments, feedback and (constructive) criticism as well as questions are most welcome. I am looking forward to a nice, engaging and rewarding journey together with you.