MC and MM Resistor and Capacitor Loading

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Not really. Mechanical damping is used for cartridges. Extra electrical damping from a low load impedance might be unhelpful. Whether this is the case would depend on how tightly coupled the mechanical and electrical aspects are. In a speaker they are sufficiently coupled that one affects the other; I don't know about a cartridge but I would suspect the coupling is smaller as efficiency is less of an issue.
 
Nice link Vince !

I have to say...
...having recently read Morgan Jones's enlightening description of 'resistor production techniques' in his exellent book 'Valve Amplifiers'...
...my current 'anxiety dreams' all concern resistors, not parallel position switches.

Having dumped 'banana plugs' years ago...
...in favour of the superb 'Neutrik Speakon' connectors...
...I couldn't agree more about 'contact pressure', especially in the signal path.
( heavy currents here, of course )

Also as a user of the equally superb Audio Synthesis DIY built PA-138 stepped-attenuator...
...which has a number of switch-contacts in the signal-path...
...the anxiety level caused by this & the long-serving speaker-cables...
...remains firmly at the bottom of my list of 'system-worries'.
( system sounds good; ALWAYS room for improvement though; we think )

Si.
 
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Received the DL-110 early. Sounds good for the most part but on some passages where high frequency has a lot of energy, I get distortion. Adjusting VTA and over hang helped a little. When adjusting, the distortion moved from the left channel to the right channel and high freq distortion became a bit less evident. Not sure what the problem is, but I still need to try to install the provided cart plate for added weight. I just hope the cart is not defective.

I might also be using the wrong loading, which is what this thread is all about anyway! :)
Using the 150 ohms used by the 103R. The 110 requires 47k. I tried my old phono pre that has a MM 47k settting, but still had distortion.

The high output cart did not help the over all gain of my system (still have to crank the preamp volume past 2 o'clock), however there is a great deal more bass, and is as enjoyable as my CD player without the glare of digital. ;)
 
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About wire wound resistors: They come in two varieties, non-inductively wound, and ordinary inductively wound. Is there any problem with whatever inductance the resistor may have so that it would be desirable to specify non-inductive ones? This is mostly to satisfy my own curiosity on the subject?
BillG



Hi again Vince

I would try using a 5K pot. maybe just on 1 channel.
ZER0-in on the optimum sound.
Remove the pot.
Measure it.
Replace with a fixed resistor ( wire-wound, OF COURSE ! )

You may just hit a 'Sweet Spot' value of...
...eg. 1001.99 Ohms ( or something ! )

Cheers.

Si.
 
Hi Bill

Morgan Jones, in his exellent book 'Valve Amplifiers'...
...says the inductance of even low value WW resistors "is trivial".

A low-value 220R one, only had 0.2deg. phase shift from 100Hz to 100KHz.
All others tested, showed "no 'measurable' deviation" of phase.

A 1.2K one, had ( depending on example measured ) between 6 & 18uH...
...an 'Ayrton-Perry wound' 1.2K had 9uH inductance.

I was slightly concerned about this, but it seems there is no real-world issue, unless they are for RF amplifiers, of MHz etc. ranges.

Wanting to build a preamp ENTIRELY with wire-wounds, I feel safe to do so.
I don't have a 'Henry meter', & probably won't bother to get one either...
...although they are cheap enough & it MIGHT be interesting !!! Mmmm.

Morgan Jones quotes the NOISE of a metal-film resistor, as 0.1uV/V dropped across them...
...I think the build-up of resistor-noise, particularly in hi-gain low-level amps, such as phono's & mic-pre's could be quite significant; microphones ( which I sometimes make ) also.

I'm surprised people aren't using them.
OK...bit more expensive maybe...
...seems like the real reason might be, they aren't easy to 'stuff' PCB's with; p2p or custom boards only.

WW's FOREVER !!!

BOO JAH !!!

Cheers.

Si.
 
Hi DF96

I can't help wondering if WW's are rejected in comercial designs ( for obvious reasons ( NOT inductance ! )...
...and this 'filters down the chain', even to the DIY builder.

As Nelson Pass says about 'super-hot' class-A amps...
...not EASY for a manufacturer to readily ( & affordably ) deal with the size & heat issues.
For the DIYer, he says, this is entirely do-able.

Not that many 'audiophool' WW's available either...
...perhaps due to 'inductance paranoia' !

The 'audiophool' resistor market, seems to have mostly been cornered, by products offering :-
Old-school, Carbon-composite.
Non-magnetic construction.
Exotic materials ( still metal-film though ).
Precision products ( 0.1 - 0.01% even ).

The HUMUGOUSLY expensive industrial 'bulk-foils'...
...seem the only option, offering a potential 'noise-reduction'.

-----------------------

Hi Vince.

Morgan Jones's book is well worth getting, just for general concepts.
TEN PAGES, just on the subject of resistors alone !
Very readable.
Exellent diagrams, tables etc.
Probably, actualy proof-read the old-school way ( ie. accurately ! ).

If you never even pick up a valve, or even consider using them...
...the book is still a gold-mine of universal audio wisdom...
...with decent 'real world' explanations of the technical stuff.

How's the Denon sounding ?

Have a look around the Net to check what people are saying about loading.
1K ( ish ) some go for 2K ( ish ) as well, I think...
...does seem 'low' compared to Denon's recs., but seems people are liking this area.
Some are putting the 'load resistor' in plugs etc...
...so probably still have the 'standard' 47K resistor in their pre-amps still in place & in parallel with the 1K etc. they load with.

More sound reports on the DL-110 please Vince !!!

Cheers.

Si.
 
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