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mikeyb
17-09-2016, 14:18
I've just received my Zu back from repair at Zu in Utah and was setting it up again and thought I'd try and get it right this time by using a calculator to work out the correct mass that the cartridge should have in relation to my Mission 774 arm.

Standard figures are:

Cartridge weight 14g
Arm effective mass 5.5g
Cartridge Compliance is 5 cu (5 x 10 –6 cm / dyne)

Now I've bodged up extra weight on the cartridge AND the counterweight and it sounds pretty good, so it must be right, right [emoji6]

I used a figure I worked out using a formula I found on the net, but I'm wondering if someone can tell me what THEY think the weight of the cartridge should be to get the figure to fall within the 8-12hz range that's supposed to be ideal.

I'll then know if my calculation is correct lol.

I'm not telling you what I have it at in case I'm found to be a complete numpty [emoji5]

PS: Photos to follow once I'm proven wrong lol

karma67
17-09-2016, 14:27
a lot i would have thought!
have you looked here?
http://www.vinylengine.com/cartridge_resonance_evaluator.php?eff_mass=5.5&submit=Submit

mikeyb
17-09-2016, 14:37
a lot i would have thought!
have you looked here?
http://www.vinylengine.com/cartridge_resonance_evaluator.php?eff_mass=5.5&submit=Submit
Lol funnily enough I have it set at a 'lot' just now, I weighed it and just wondered if I'd calculated correctly.

I tried looking at the vinylengine version but it just confused me, ( actually that's not true, it's the Denon compliance figures that confuses me with the 10hz 100hz thing ) I found a formula to try and that's what I used.

Although I think I still need to add a few grams yet to be 100%

karma67
17-09-2016, 15:24
lol thats why i posted the same thread a while back for my cartridge,all that dyne bollocks goes right over my head!
my thread is here, http://theartofsound.net/forum/showthread.php?46353-cartridge-resonance-frequency

if you have no luck shoot the members who helped me a pm :)

helma
17-09-2016, 15:27
I have no idea what the actual compliance @*10Hz is for the DL-103 and I've never owned one, but my guess is it'll be somewhere around 10, say 8-12. Assuming that, the minimum would probably be around 15-20g (tonearm/headshell + cartridge combined) and you could go as high as 40g or even more, depending what the compliance actually is.

Some cartridges / combos might prefer the res. freq on the low (or high) side for best sound quality, and perhaps the DL-103 is one of those judging from all the comments it needs some mass to shine.

mikeyb
17-09-2016, 15:33
I have no idea what the actual compliance @*10Hz is for the DL-103 and I've never owned one, but my guess is it'll be somewhere around 10, say 8-12. Assuming that, the minimum would probably be around 15-20g (tonearm/headshell + cartridge combined) and you could go as high as 40g or even more, depending what the compliance actually is.

Some cartridges / combos might prefer the res. freq on the low (or high) side for best sound quality, and perhaps the DL-103 is one of those judging from all the comments it needs some mass to shine.
I think I read somewhere that you multiply the 5 by 1.8 which gives 9 so that might be right enough.

petrat
17-09-2016, 15:46
Ask Barry :D

.... which could become my standard response to a lot of questions on this forum :lol:

mikeyb
17-09-2016, 16:18
Ask Barry :D

.... which could become my standard response to a lot of questions on this forum [emoji38]
Could make it a Stickie lol

"Ask Barry"

[emoji39] [emoji1]

mac72
17-09-2016, 17:13
Assuming 9cu is correct to fall within 8-12Hz total weight of arm, headshell and cartridge is in range 19.5-44 gram , so there is massive room to play with .
103 loves high mass arms I would try to be well above 30g.

mikeyb
17-09-2016, 19:15
Assuming 9cu is correct to fall within 8-12Hz total weight of arm, headshell and cartridge is in range 19.5-44 gram , so there is massive room to play with .
103 loves high mass arms I would try to be well above 30g.
mmmmmmm interesting 😉

mac72
17-09-2016, 20:40
mmmmmmm interesting ��

Resonance freq is calculated from following formula:
f = 1000 /(2 * π * √ (M * C)) where:

if you derive M from it , as follow:
√(M * C) =1000/2*f*π
√(M * C) =159.155/f
M * C = (159.155/f)sqr

you end up with :
M = (159.155/f)sqr/C

to achieve 8Hz you need :
M = (159.155/8)sqr/9
M= 43.976 g

for 12 Hz:
M = (159.155/12)sqr/9
M = 19.545 g

karma67
17-09-2016, 20:58
You might just as well written that in Arabic mate lol

Barry
17-09-2016, 21:04
The dynamic compliance of the Denon 103 is 5cu, measured at 100Hz. At 10Hz the compliance is multiplied by a factor of 1.5 - 2.0.

The total mass (mass of cartridge in the metal body + effective mass of the arm (including headshell (if used)) + say, 0.5g for the fixings) = 20g.

So taking the lower mutiplication factor, the calculated low frequency resonance is 13Hz, and taking the higher multiplication factor, the figure is 11.25Hz.

Neither figure should cause any problem.



I have a standard Denon 103 mounted in a Fidelity Research S/3 headshell and the total weight, including fixings, is 28.8g. I use it in an SME 3009 (non-improved) arm, and the calculated low frequency resonance lays between 8.75 and 10.1Hz.

mac72
17-09-2016, 21:12
You might just as well written that in Arabic mate lol

This online calculator is quite handy:
http://www.resfreq.com/resonancecalculator.html

mikeyb
17-09-2016, 22:59
Thanks for the brilliant and comprehensive replies, it looks like am no a dunderheed after all as I have it setup up at around 30g at the cartridge and I've added a 2nd counterweight to get it to balance, tracking set at 2.5g as per Zu's 103 manual and it all sounds really good.

Now don't laugh !

http://uploads.tapatalk-cdn.com/20160917/a142b2800a1a70f38e0db35c682e6c72.jpg

http://uploads.tapatalk-cdn.com/20160917/904cfea6a597e5b4c5bd49ecf9aa33e8.jpg

I might swap back in my MC25fl cartridge and set it up using the calculator too and see what difference it makes. Although I'll probably leave that until I get new tags on spare 774 arm.

Thanks for all your help and calculations.

Mike.

walpurgis
17-09-2016, 23:20
What the heck is going on with that 774?

I have my own ideas about mods, but I can't figure quite what you've been up to.

And. I reckon the MC25FL will see off the ZU.

karma67
18-09-2016, 05:20
christ! if you have to add that lot to get the cartridge to sound good then its gotta be the wrong cartridge for that arm??
get the mc25 on it,its a lovely cartridge.

mac72
18-09-2016, 08:42
christ! if you have to add that lot to get the cartridge to sound good then its gotta be the wrong cartridge for that arm??
get the mc25 on it,its a lovely cartridge.

Certainly not a best match but one could get one of this (3 or 8 gram):
http://www.ebay.co.uk/itm/ISOkinetik-CARTRIDGE-STABILISER-FOR-DENON-103-DL-103R-BRASS-/171258625981?hash=item27dfcf3fbd:m:mRUxnSyWl02Mf91 SNk6q1rw


and :
http://snvinyl.co.uk/EZ-Mount-Cartridge-Mounting-Screw-Set-The-EZ-Mount-system-allows-for-phono-cartridge-mounting-with

to add some weight to total mass.

mikeyb
18-09-2016, 13:31
I've switched back to my Ortofon MC25fl and using the same formulas I don't need any additional mass to have that running good. I have a spacer added to gain some height at the cartridge so I can get the arm dead level, this adds 3g to the cartridge and this gives a resonance figure of 8.5 or thereabouts so I'm assuming this is good. Certainly sounds great.

I think with the Zu Denon being more suited to higher mass arms that it will be sold off and I'll try and buy something else as a spare 😉

struth
18-09-2016, 14:06
http://www.ebay.co.uk/itm/Shure-M55E-Stereo-Moving-Magnet-Cartridge-with-Genuine-Stylus-and-Guard-/252541598898?hash=item3acca6fcb2:g:bGMAAOSwTA9X2wt 4

Barry
18-09-2016, 19:45
http://www.ebay.co.uk/itm/Shure-M55E-Stereo-Moving-Magnet-Cartridge-with-Genuine-Stylus-and-Guard-/252541598898?hash=item3acca6fcb2:g:bGMAAOSwTA9X2wt 4

Lovely - a brown-bodied M55E with white lettering, just like the one I used to have. :) But the current bid is £51 with seven days to go, so it will go for a lot more than I feel it's worth.

Barry
18-09-2016, 19:54
christ! if you have to add that lot to get the cartridge to sound good then its gotta be the wrong cartridge for that arm??
get the mc25 on it,its a lovely cartridge.

I regard both the Denon 103C and the Ortofon MC25FL as my 'everyday' cartridges. And as good though they are, I've recently been auditioning an Ortofon MC200 'Concorde' cartridge - and I have to say it wipes the floor with the other two 'nails'.

mikeyb
18-09-2016, 22:04
I regard both the Denon 103C and the Ortofon MC25FL as my 'everyday' cartridges. And as good though they are, I've recently been auditioning an Ortofon MC200 'Concorde' cartridge - and I have to say it wipes the floor with the other two 'nails'.

I'll check it out [emoji6]

mikeyb
18-09-2016, 22:06
I regard both the Denon 103C and the Ortofon MC25FL as my 'everyday' cartridges. And as good though they are, I've recently been auditioning an Ortofon MC200 'Concorde' cartridge - and I have to say it wipes the floor with the other two 'nails'.

Doh! [emoji15] [emoji1]

struth
18-09-2016, 22:16
I regard both the Denon 103C and the Ortofon MC25FL as my 'everyday' cartridges. And as good though they are, I've recently been auditioning an Ortofon MC200 'Concorde' cartridge - and I have to say it wipes the floor with the other two 'nails'.

Ive seen the price :mental: and its concolde I think

walpurgis
18-09-2016, 22:25
I've recently been auditioning an Ortofon MC200 'Concorde' cartridge - and I have to say it wipes the floor with the other two 'nails'.

I'm aware of the MC2000, but not the MC200. I Don't know that one Barry. What's the score with it?

Barry
19-09-2016, 12:00
Doh! [emoji15] [emoji1]

It's early days with this one, and with time I'm sure I'll come to a more 'measured' opinion. Let's just say I'm pulling out record after record to see how they play with the new nail - something I haven't done since I reinstalled a Decca Mk. VI after a gap of ten years.


I'll still be keeping my Denons though - I'm an incorrigible cartridge swapper!

Barry
19-09-2016, 12:27
I'm aware of the MC2000, but not the MC200. I Don't know that one Barry. What's the score with it?

https://sp.yimg.com/ib/th?id=OIP.Ma5c1fbd3a497d3dc62393819120db685o0&pid=15.1

https://tse1.mm.bing.net/th?id=OIP.M5e0a5e8d4bfb1366edced91ced1b528co0&pid=15.1&P=0&w=300&h=300


This is a moving-coil cartridge from Ortofon, with integral headshell which plugs directly into any arm with an EIA bayonet connector. It was the first to use the ‘Concorde’ shaped body. As far as I know it wasn’t in production for long - I don’t know why, perhaps there was insufficient interest, or maybe buyers didn’t like it: Hi-Fi Choice gave it an indifferent review in their omnibus cartridge review series.

It weighs 16.5g, has a fine line stylus, a dynamic compliance of 13cu, a low coil resistance of 3 Ohm and a very low output of 90uV (at 5 cm/s).

Bought about a year ago from Switzerland, but I have only just got around to using it. Mounted in an SME 3009 (improved) arm, the calculated low frequency resonance is 10.5Hz, and I’m getting secure tracking at 1.6g with a bias setting of 1.5g.

Early days yet, but I’m delighted with the delicacy and poise this cartridge displays.

mac72
19-09-2016, 18:05
There was 1/2" headshell mounted version as well:
http://www.ortofon.com/media/15191/ortofon_mc_100_mc_200_p003.pdf

few could be found on E-bay (from Japan) , prices £300-£750