another cartridge loading question

[karma67]

my denon HA-500 head amp has, 24db and 32 db,into mm stage at 2.4mv/47kohms
my pre amp has a mc stage with 200 ohms/23db,100ohms/30db and 50ohms/34db

ive tried to get the denon 103m singing but it would seem from what ive read i need 65 to 70 db range.
its specs are 0.12mv output with 40ohms Output Impedance.

what options do i have before i give up and sell it.

cheers guys :)

[Barry]

The Denon 103M has an output voltage of 0.12mV. You need to raise this output voltage to about, say, 5mV to feed an MM input of an amplifier. You thus need a head amplifier or SUT to provide 32dB voltage gain.

Your cartridge has a coil impedance of 40Ohm, so ideally needs a load impedance of 400Ohm or greater. This excludes the use of an SUT, so I would compromise and use the 100 Ohm/30dB setting of your preamp MC stage. Not perfect, as the effective gain will be 27dB, giving an effective output of 2.7mV; but probably good enough.

Have you tried this option? Were you unhappy with the overall performance?

[karma67]

hi barry,yes i tried all the mc stage options,it sounds very bass shy in comparison to the 103SA i normally use,perhaps its just the nature of the beast?

if you read reviews on the 103M including rextons you'd think you'd have a killer cartridge,alas ive found the opposite,nice top end but thats about it which made me think it was down to it not being loaded correctly,oddly from what ive read online some say its similar to the dl-s1 which also has comments of being bass shy.

[Barry]

Sorry, the only Denon cartridge with which I have had any experience of is the standard DL103. I have two samples and wouldn't describe them as bass light at all.

What arm and headshell are you using?

[karma67]

The 103m is a different animal to the stock 103.
It has a boron cantilever, higher compliance and an elliptical tip.
I’ve tried it in my zeta 16g mass and Alphason hr100 11g, it sounded best in the Alphason but still not on par with the 103sa.

[phonomac]

The Denon HA-500 is a headamp, as you know, so you would use either the HA-500, or the MC input of your preamp.

Assuming you are using the Nakamichi CA-5 it looks as if the gain from MM in to preamp out is around 39dB, so using the internal MC section you would have 73, 69 and 62 dB as overall gain options, with the corresponding cartridge loads of 50, 100 and 200 ohms respectively.

With the HA-500 you will have 71 and 63 dB as overall gain options, with 100 ohm input impedance.

[Stryder5]

I had similar bass issues with a variety of cartridges, found that some cartridges like to be mounted tail down not parallel. Mounted like this the bass appears.

[karma67]

I’m using a Denon 103m Andrew into the mc stage in my Nakamichi ca-5 pre amp, to me it sounds best with the 100 ohms setting.
My every day cartridge is a Denon 103sa both are different than the stock 103 and 103 r.

It would seem that I’m ok with my loading options so I guess the two cartridges are just different and I’m used to hearing the 103sa which certainly does not lack in the bass region.

Thanks too Barry and Angus for taking the time to check out the specs and do the maths, it’s much appreciated :cool:

[karma67]

regarding the denon ha-500 head amp,i was just listing its specs for more options,its currently away at the moment being re capped and upgraded.
as you can probably tell i struggle with cartridge loading :scratch:

as ive said already i think its a case of being 2 different sounding cartridges and me being used to the 103sa,this happened before when i went from a decca,i just didnt know if my head amp or mc stage were suitable for the 103m being a very low output.

[karma67]

.

Assuming you are using the Nakamichi CA-5 it looks as if the gain from MM in to preamp out is around 39dB, so using the internal MC section you would have 73, 69 and 62 dB as overall gain options, with the corresponding cartridge loads of 50, 100 and 200 ohms respectively.

With the HA-500 you will have 71 and 63 dB as overall gain options, with 100 ohm input impedance.

ah ! with my lack of understanding i didnt realise you add the gain from the mm to pre amp out to the gain of the mc section.
cheers angus :cool: