How do we know if Integrated Amp with In-Built Phono Matches/Mismatches with MC Phono Cartridge?

[Spider27]

Hello,

 

I found that most of specs from HifiEngine for integrated amplifiers shows only Input Sensitivity and Signal to Noise ratio figures when phono cartridge specs show Output and Load Impedance figures.

 

For instance, well known cartridges such as Denon DL-103, DL-103R and Benz Micro MC Gold have specs as below;

 

Denon DL-103
Output voltage    0.3 mV
Frequency range    20 Hz - 45 kHz
Output impedance    40 ohms
Weight    8.5 g
Tracking - 2.5g

Load Impedance 100 ohms min.

 

Denon DL-103R
Output Voltage 0.25 mV
Output Impedance 14 ohms
Frequency Response 20 Hz to 45 kHz
Mass 8.5 g
Tracking - 2.5g
Load Impedance 100 ohms min.
(40 ohms when using a transformer)

 

Benz Micro MC GOLD
Output Voltage
3.54 cm/sec - 0.5
Stylus Shape - .3 X .7 mil
Internal Ohms - 20
Loading Range - >200
Weight - 5.7
Compliance - 15
Tracking - 1.7 - 2.0

 

And, typical Integrated amplifiers' specs show as below (from typical Denon and Pioneer Integrated amplifiers);

 

( Amp A )

Input sensitivity: 0.09mV (MC), 1.8mV (MM), 120mV (line)
Signal to noise ratio: 75dB (MC), 80dB (MM), 82dB (line)

Output: 120mV (line), 0.95V (Pre out)

 

( Amp B )

Input sensitivity: 0.2mV (MC), 2.5mV (MM), 150mV (line)
Signal to noise ratio: 76dB (MC), 94dB (MM), 110dB (line)
Output: 150mV (line)

 

( Amp C )

Input sensitivity: 0.37mV (MC), 2.5mV (MM), 320mV (line)
Signal to noise ratio: 74dB (MC), 89dB (MM), 105dB (line)
Output: 320mV (line), 1V (Pre out)
 

Is there a way to figure out if  the amp with built in phono may/may not match the specific cartridge with those information only?

 

Welcome any input and guidance on this. Thank you..

 

Edited August 3, 2021 by Spider27

[andyr]

4 minutes ago, Spider27 said:

Hello,

 

I found that most of specs from HifiEngine for integrated amplifiers shows only Input Sensitivity and Signal to Noise ratio figures when phono cartridge specs show Output and Load Impedance figures.

 

And, typical Integrated amplifiers' specs show as below (from typical Denon and Pioneer Integrated amplifiers);

 

( Amp A )

Input sensitivity: 0.09mV (MC), 1.8mV (MM), 120mV (line)
Signal to noise ratio: 75dB (MC), 80dB (MM), 82dB (line)

Output: 120mV (line), 0.95V (Pre out)

 

( Amp B )

Input sensitivity: 0.2mV (MC), 2.5mV (MM), 150mV (line)
Signal to noise ratio: 76dB (MC), 94dB (MM), 110dB (line)
Output: 150mV (line)

 

( Amp C )

Input sensitivity: 0.37mV (MC), 2.5mV (MM), 320mV (line)
Signal to noise ratio: 74dB (MC), 89dB (MM), 105dB (line)
Output: 320mV (line), 1V (Pre out)
 

Is there a way to figure out if  the amp with built in phono may/may not match the specific cartridge with those information only?

 

Welcome any input and guidance on this. Thank you.

 

Amp C (0.37mV) will accept LOMCs which have an output from 0.35 - 4mV quite happily - and will probably work fine with carts from 0.3 - 0.5mV.

 

Amp B (0.2mV) will accept LOMCs which have an output from 0.18 - 3mV quite happily - and will probably work fine with carts from 0.015 - 0.4mV.

 

Amp A (0.09mV) will accept LOMCs which have an output from 0.06 - 0.15mV quite happily - and will probably work fine with carts from 0.05 - 0.2mV.

 

However, a very important point is ... what load options to these integrated amps offer, in MC mode?

 

Andy

 

[Spider27]

15 minutes ago, andyr said:

 

Amp C (0.37mV) will accept LOMCs which have an output from 0.35 - 4mV quite happily - and will probably work fine with carts from 0.3 - 0.5mV.

 

Amp B (0.2mV) will accept LOMCs which have an output from 0.18 - 3mV quite happily - and will probably work fine with carts from 0.015 - 0.4mV.

 

Amp A (0.09mV) will accept LOMCs which have an output from 0.06 - 0.15mV quite happily - and will probably work fine with carts from 0.05 - 0.2mV.

 

However, a very important point is ... what load options to these integrated amps offer, in MC mode?

 

Andy

 

Thank you very much, Andy. I think that I got the rough idea what to check.

 

Have i understood correctly that Input sensitivity of amp is to match with phono output voltage as closely as possible?

 

And, may I ask why Denon DL-103 (DL-103R) output impedance is 40 ohm (14 ohm) but load impedance of amplifier needs to be 100 ohm or bigger?

Is it similar concept to pre-pwr amp impedance match (pwr amp input impedance to have at least 100 times bigger than pre amp output impedance) to achieve good damping factor?

 

Unfortunately, none of those integrated amps have any loading option. They just have MC Phono Input. (sigh).

[andyr]

1 minute ago, Spider27 said:

Thank you very much, Andy. I think that I got the rough idea what to check.

 

My pleasure, S27.  

 

1 minute ago, Spider27 said:

Have i understood correctly that Input sensitivity of amp is to match with phono output voltage as closely as possible?

 

Yeah, basically.  

 

The sensitivity figure is the signal level you need to feed it, to get the 'normal' output.  That being said ... the amp will be able to cope with an input signal which is a bit lower or a bit higher - just how much depends on:

• the gain which the preamp section of the integrated has, and
• the overload margin in the phono stage section.

 

1 minute ago, Spider27 said:

And, may I ask why Denon DL-103 (DL-103R) output impedance is 40 ohm (14 ohm) but load impedance of amplifier needs to be 100 ohm or bigger?

Is it similar concept to pre-pwr amp impedance match (pwr amp input impedance to have at least 100 times bigger than pre amp output impedance) to achieve good damping factor?

 

Exactly!    Except the pre-power impedance match is not generally thought of as "at least 100 times bigger" ... it should be more than 20x ... 50x is nice ... but 100x is perfect!  

 

In the case of the cart-phono stage match, my experience is that the load should be between 10x and 100x coil impedance.  So I would say you have picked up a major anomaly in Denon's cart specs:

• the optimal load for the DL-103 will be a lot higher than the optimal load for a DL103R
• and even for the DL-103R I would say that 100 ohms is too low!  To be fair, Denon says in both cases "a minimum of 100 ohms" - they say this because makers of phono stages often choose 100 ohms as the load they offer.  

 

1 minute ago, Spider27 said:

Unfortunately, none of those integrated amps have any loading option. They just have MC Phono Input. (sigh).

 

Which probably means they selected 100 ohms.  

 

Andy

 

[Spider27]

23 minutes ago, andyr said:

In the case of the cart-phono stage match, my experience is that the load should be between 10x and 100x coil impedance.  So I would say you have picked up a major anomaly in Denon's cart specs:

• the optimal load for the DL-103 will be a lot higher than the optimal load for a DL103R
• and even for the DL-103R I would say that 100 ohms is too low!  To be fair, Denon says in both cases "a minimum of 100 ohms" - they say this because makers of phono stages often choose 100 ohms as the load they offer.  

Andy

 

Awesome. Thank you, Andy.

 

If load needs to be 10x to 100x coil impedance, have I understood correctly that Denon DL-103 needs between 400~ 4K ohm load and DL-103R needs 140~1.4k ohm load?

[andyr]

54 minutes ago, Spider27 said:

 

Awesome. Thank you, Andy.

 

 

NP, Dennis.

 

54 minutes ago, Spider27 said:

 

If load needs to be 10x to 100x coil impedance, have I understood correctly that Denon DL-103 needs between 400~ 4K ohm load and DL-103R needs 140~1.4k ohm load?

 

 

That's what I would recommend - yes.  

 

Andy

 

[Spider27]

The Amp #1 is my own Accuphase E-203 which I enjoy using it. The other two amps are Denon vintage amps that I got spec details random internet search. I thought that Denon may be a good match with DL-103 since they are come from same company.

 

According to the info above, my own amp is the least ideal match with Denon DL-103 that I am trying to pair with. 

[andyr]

25 minutes ago, Spider27 said:

The Amp #1 is my own Accuphase E-203 which I enjoy using it.

 

According to the info above, my own amp is the least ideal match with Denon DL-103 that I am trying to pair with. 

That depends on what loading it offers for an MC cart!  

 

I was able to find a manual for the E-203 which said that MC load is - as I expected - 100 ohms.  But the manual says it has sufficient headroom not to be overloaded by the 0.3mV of the DL-103!  

 

However, it seems for MM, you can select either 47K or 100K input load.  So one option is to use the MM input on the E-203 but 'feed' this with a head amp.  (So the arm cable plugs into the head amp and the output of the head amp goes into the MM inputs on the E-203.)

 

You then apply loading on the head amp, to discover which value makes the DL-103 sound its best.

 

Normally, I would be able to lend you one, to try out ... but I've just sent it up to Tasebass, in Sydney, for a 'play'.  

 

Andy

 

 

 

Edited August 3, 2021 by andyr

[Spider27]

Just tried two sets of load plugs that i made last night. One pair with 300R and the other pair with 680R.

 

The difference is not very much and I personally prefer 680R load on MM Input with 47K. It sounds a bit more fuller with more bottom end. 

 

My amp has 3 Input Load setting on MM section. 100, 47K, 100K.

 

With 100 input load, sounds a bit muddy, 47K sounds right and 100K a bit more thin but hard to tell the difference between 47K and 100K.

[andyr]

1 hour ago, Spider27 said:

Just tried two sets of load plugs that i made last night. One pair with 300R and the other pair with 680R.

 

The difference is not very much and I personally prefer 680R load on MM Input with 47K.

 

Are you saying you:

• plugged your arm cable into the MM inputs on your Accuphase E-203 ... which has , selectable, 47K input loading or 100K input loading
• then you were able to select 60db gain (so your DL-103 was able to drive the amp)
• then you used your 300R and 680R load plugs to adjust the 47K default loading?

If so ... where did you plug in the 300/680R load plugs?

 

Andy

 

 

[Spider27]

3 minutes ago, andyr said:

 

Are you saying you:

• plugged your arm cable into the MM inputs on your Accuphase E-203 ... which has , selectable, 47K input loading or 100K input loading
• then you were able to select 60db gain (so your DL-103 was able to drive the amp)
• then you used your 300R and 680R load plugs to adjust the 47K default loading?

If so ... where did you plug in the 300/680R load plugs?

 

Andy

 

 

 

Hi Andy

 

I have used this phono plugs (refer attached photo).

 

Put phono RCA Plug In and Resistor Plug on top and out to E-203 MM Phono Input.

 

Not sure about gain. Is there a way to select different gain on E-203? I thought that it only has MM and MC input and MM has 3 Input Load Setting on the front faceplate (100, 47K, 100K)

 

 

[andyr]

13 minutes ago, Spider27 said:

 

Hi Andy

 

I have used this phono plugs (refer attached photo).

 

Put phono RCA Plug In and Resistor Plug on top and out to E-203 MM Phono Input.

 

 

 

Aah, right, you used some 'T' connectors.    Excellent!

 

Now you said before (with the 'T' connectors into the mm RCA inputs);

 

1 hour ago, Spider27 said:

With 100 input load, sounds a bit muddy, 47K sounds right and 100K a bit more thin but hard to tell the difference between 47K and 100K.

 

Yes, when you selected the 100R option on the MM input (using the 680R plugs) ... the resulting combined load would've been 87R.  So no wonder it sounded 'muddy'!

 

Selecting the 47K option would've given you a combined load of 670R - while the 100K option would've meant a combined load of 675R.  So not surprising you couldn't hear much difference!  

 

2 hours ago, Spider27 said:

Just tried two sets of load plugs that i made last night. One pair with 300R and the other pair with 680R.

 

The difference is not very much and I personally prefer 680R load on MM Input with 47K. It sounds a bit more fuller with more bottom end.

 

And I'm not surprised that the 680R plugs sounded better than the 330R plugs (using the 47K MM load option) - given the DL-103 has 40R coil impedance!  Perhaps you should try some more plugs with higher load values?   (Say, 1K, 2K2, 3K3 and 4K7.)

 

30 minutes ago, Spider27 said:

 

Not sure about gain. Is there a way to select different gain on E-203? I thought that it only has MM and MC input and MM has 3 Input Load Setting on the front faceplate (100, 47K, 100K)

 

 

I only mentioned 'gain' because I was surprised that you could feed the DL-103 into the MM input and still get some sound from your speakers!    Even so, with such a low input signal level ... I suggest your SQ would improve if the signal into the MM RCAs was, say, 6mV instead of 0.3mV.  At the very least, the noise floor heard from the spkrs, when the stylus wasn't touching the grooves, would be lower.

 

Andy

 

[Spider27]

14 minutes ago, andyr said:

And I'm not surprised that the 680R plugs sounded better than the 330R plugs (using the 47K MM load option) - given the DL-103 has 40R coil impedance!  Perhaps you should try some more plugs with higher load values?   (Say, 1K, 2K2, 3K3 and 4K7.)

 

I only mentioned 'gain' because I was surprised that you could feed the DL-103 into the MM input and still get some sound from your speakers!    Even so, with such a low input signal level ... I suggest your SQ would improve if the signal into the MM RCAs was, say, 6mV instead of 0.3mV.  At the very least, the noise floor heard from the spkrs, when the stylus wasn't touching the grooves, would be lower.

 

Andy

 

Thank you for those suggestions, Andy. I do have 1K and 4K7 resistors in my drawer so will try them too.

 

Re: gain, I am lost here... Not sure how to increase from 0.3mv to 6mV. Do I need some sort of active or passive SUT to increase the gain by 20x ?

 

My speakers are 94db sensitivity so do not need much power and I was listening with volume pot 8~9 o'clock position when I was using typical MM cart and now bumping up to 11 o'clock position with load plug & DL-103 cart which is loud enough and sounds good to me.  

[andyr]

Just now, Spider27 said:

Thank you for those suggestions, Andy. I do have 1K and 4K7 resistors in my drawer so will try them too.

 

  Please let us know how they go!  Don't forget you could also leave out any load plugs ... and see what 47K loading sound like.

 

Just now, Spider27 said:

Re: gain, I am lost here... Not sure how to increase from 0.3mv to 6mV. Do I need some sort of active or passive SUT to increase the gain by 20x?

 

Yes, you need an active head amp - which will lift the signal level by 20x, whilst still allowing you to have high loading.

 

(A 1:20 SUT would increase the signal level by 20x but would deliver a loading of 118R if you selected 47K on your Accuphase ... and 250 ohms if you selected 100K.)

 

Just now, Spider27 said:

My speakers are 94db sensitivity so do not need much power and I was listening with volume pot 8~9 o'clock position when I was using typical MM cart and now bumping up to 11 o'clock position with load plug & DL-103 cart which is loud enough and sounds good to me.  

 

Shows how good your Accuphase E-203 is!    Sure it will be loud enough but the higher the input signal level is ... the better the SNR is.

 

Andy

 

[Spider27]

Out of curiosity, I unplugged Load Plugs and straight to 47K MM input and it surprisingly sounds good, too. 

 

Comparing with load plug (680R) or without plug, there is more presence on mid-range without load plug and more output. I thought that MC cart cannot be run with MM phono Input. What's going on? 

 

With load plug in, less output so need to increase volume a bit and sound more balanced overall.

[andyr]

10 minutes ago, Spider27 said:

With load plug in, less output so need to increase volume a bit

 

Yes, that's just the maths of how the input signal is affected by the load that the cart's output coils 'see'.

 

11 minutes ago, Spider27 said:

Out of curiosity, I unplugged Load Plugs and straight to 47K MM input and it surprisingly sounds good, too. 

 

Interestingly (to me, anyway!), both VdH and Herr Lucaschek ("Mr Benz") recommend their carts be run with no loading - ie. 47K!

 

12 minutes ago, Spider27 said:

I thought that MC cart cannot be run with MM phono Input. What's going on? 

 

Yes it's a widely promulgated myth ... possibly originated by those who sell SUTs - given SUTs reduce the load impedance considerably?  

 

I have found that as you go up in load value ... you get more air in the soundstage ... but bass can become uncontrolled.  For instance, with my Benz LP, whilst there was lovely "air" ... the bass on my Bob Marley records was too floppy at 47K.  Reducing the load to 3K3 I found was the optimal combination of 'air' and firm bass.

 

20 minutes ago, Spider27 said:

Comparing with load plug (680R) or without plug, there is more presence on mid-range without load plug

 

Given you've heard how the DL-103 sounds @ 47K ... that's why you need to experiment with higher loads than 680R.  

 

With those 'T' connectors, your Accuphase E-203 has enough gain to be able to:

• cope with 0.3mV into MM
• and allow you to experiment with loading.

 

So you'll be able to work out which loading makes the DL-103 sound its best.  You may well find that 47K is the sound you like best with the DL-103!

 

Then, "the icing on the case" will be to use a head amp before the E-203, to increase the signal level, to improve the SNR.

 

Andy

 

[Spider27]

Just tried 4 different value load plugs such as 680R, 1K, 2K7 and 4K7. My personal preference is 1K and 2K7. 

 

680R sounds very smooth but lacks a bit detail. 4K7 has good details but a bit grainy and lose a bit of bottom end.

 

There is definitely difference between 1K and 2K7 and preference depends on what records or genre of music plays. I think that I would be happy with either but if I have to choose, I would go with 2K7 which offers good tonal balance for me.

 

[Spider27]

I will have to correct myst last comment. After further testing, 4K7 sounds better than others for me. 2K7 sounds smooth and likes it but 4K7 offer a bit more detail and yet maintain good balance. I may test 3K one to see if it is better match but happy with 4K7 loading.

 

Again, thank you for your tip and suggestions, @andyr