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.
And here is my report out on the checks I wanted to do before taking any next steps..

First the alignment:
I used the two point alignment aid supplied with the Hifi News and Record Review test record.
The current DL-301 cartridge seems to be aligned perfectly on each point. Azimuth (as far as I can see) is also fine.

Secondly test results from the record tracks:
S1B1: OK
S1B2: OK, a slight emphasis on the right channel
S1B3: OK, a slight emphasis on the right channel
S1B4: OK
S1B5: OK
S1B6: OK, no buzz
S1B7: OK, no buzz
S1B8: Not OK; Buzz in the right channel
S1B9: Not OK; Load buzzin the right channel

S2B1: OK, no buzz
S2B2: ~10 Hz
S2B3: ~10 Hz
S2B4: OK
S2B5: Not done since my amp cannot go mono
S2B6: OK; a little rumble @ 100 Hz with a very high(!) volume
S2B7: OK
S2B8: Not OK; A little buzz in the right channel.

A few notes with the test:
determining the resonance frequency was very hard. I could not see any of the 'excitement' or 'wobble' that the test record manual predecited. It was also very hard, soundwise to determine the resonance frequency. After a lot of repeating I decided on 10 Hz. But it was not very obvious at all.

I do not know how to interpret the results for S1B8. I guess a little buzz in one channel in this test is ok. I cannot do anything with anti skating on the DP-35F anyway.
But there seems to be a slight systemic error in the setup since the right channel is often either slightly emphasized or breaking down first.

Then effective arm mass:
I measured the following:
Resonance Frequency: 10 Hz
Headshell weight with cartridge, shim plate and nuts and bolts: 10 gr
Cartridge compliance: 13
Applying the above formula brings me to an effective arm mass of 9,5 gr.

Then, finally, the calculated resonance frequency for the DL-103:
Arm mass: 9,5 gr
Headshell weight (essentially adding the weight difference between DL-301 and DL-103): 12,5 gr
Compliance: 5
Applying the above formula brings me to a resonance frequency of: 15,2 Hz.

This is over the high limit of what is normally considered to be OK.

A hard conclusion is difficult as there are a few points where a measuring error could greatly influence the end results. That aside I have a few thoughts:
1) Apparently the damping in the arm is very good since it was so hard to determine the resonance frequency. This may play a positive role in reducing the resonances of the mounted cartridge.
2) Adding a little weight to the headshell brings down the (calculated) resonance frequency into (almost) the desired limits.
The combination of #1 and #2 may make the DL-103 cartridge work in the DP-35F.
As an addendum to my last post a few things:

Firstly I had the idea of recording the resonance tracks of the test record to see if I could see anything around the resonance frequency. So I connected my laptop to the amp and recorded the track using Audacity.
The idea was certainly nice but the result a bit disappointing in that I was not able to recognize a clear difference in the signal at any frequency (the test record instructions said the 1 kHz signal would be wobbling at the resonance frequency; my idea was that this should be visible. But no). The best I could see is that the signal gets more stable below 9 Hz with a 'wobbling' change from more unstable from 22 Hz - 10 Hz to more stable around 8 Hz and below. Not sure what to think about that though... In any case: it reinforces my impression that for my current setup the resonances are not very manifest and may be damped pretty good...

Secondly I decided to record all the tracks of the test record in the same way using the Audacity software. In this way I can compare them later on. Just to be sure..

In the meantime the DL-103 is underway....
Yesterday I received the DL-103. After removing the gem from its box it becomes immediately apparent that the cartridge is heavier and bigger as my DL-301. It looks simple and it has no stylus protector as my DL-301 has.

I mounted the cartridge in the headshell. I used the small shim plate that was used with my DL-301 between the headshell and the cart and mounted a small 2 gr weight plate on the top of the headshell to increase the effective arm mass. Total headshell weight increased from 10 gr to 17 gr.. This will most likely have a multiplied effect on the effective arm mass since the effective arm mass is calculated as mass x length. I aligned the cart using the two point alignment protractor supplied with the HNRR test record. I set the tracking force and Q-damping to 2.5 gr. Azimuth and antiskate settings are not available on my TT so I need not adjust anything on these.

Using these settings I played the test record with below results:
S1B1: OK
S1B2: OK
S1B3: OK
S1B4: OK
S1B5: OK
S1B6: A little buzz in the right channel
S1B7: A little buzz in the right channel
S1B8: A bit more buzz in the right channel
S1B9: Very severe buzzing in the right channel to the extend that sound in the left channel disappeared.

S2B1: Very little buzz
S2B2: Resonances between 15 and 11 Hz. On average ~13 Hz.
S2B3: Resonances between 10 and 14 Hz. On average ~12 Hz.
S2B4: Very little buzz
S2B5: Not done since my amp cannot go mono
S2B6: OK; much more rumble as with the DL-301!
S2B7: OK
S2B8: A little buzz
These results are a little worse compared with the DL-301.

Then I played a few records.
What is immediately apparent is the delightful sound. Really beautiful and much better than my old DL-301 (that was worn!).
Not only is the sound beautiful, the soundstage is very wide (beyond the speakers L/R) and deep. Instrument placement and holography are only so-so and a bit muddled. Details are amazingly clear. Tonal balance is nice but bass is a bit rough and uncontrolled. I will revisit this later on as the cart has to first break in.

Something else that became apparent is that there is a slight emphasis on the right channel. That was already the case with the DL-301 but seems to be a little bit more with the DL-103.

It seems that the compliance thing with my (light) arm is actually not a problem (with the mounted additional weight) since the resonance is within the desired limits. That is better as I expected!
The cart needs additional tweaking though and additional investigation on the channel emphasis is needed.
I'd suggest increasing tracking force to 2.6 grams-sound will become more focused and controlled. More like real music less like hi-fi. That's based on spending a lot of time with the 103R.

Around the 15-20 hour mark is pretty magical, at least with the R. Up to that point the cartridge will sound a bit thin and steely. The bass becomes thunderous at around the 15-20 hour mark and the cartridge smooths out considerably. It will improve subtly into the 50 hour mark but my experience with 2 103R's is that the 15-20 hour mark is very significant.