Phono Amp Spec’s

[No Regrets]

Hello

Can someone please help me understand the following…

*Maximum Input Voltage
64dB = 5.7mV
70dB = 2.9mV
34dB = 180mV
40dB = 90mV

I would be using a Benz Micro Ruby ZH moving coil cartridge with this phono amp.
It’s output is rated at .7mV@3.54cm/sec which I believes equates to .998mV @ 5cm/sec.

1. Am I understanding this correctly, that my roughly 1mV cartridge would be fine going into this 64dB MC input?

2. Is there a way to know what the dB overload margin would be with 1mV @1khz as well as the low, mid, and high frequencies going into this 64dB MC input?

Secondly,
As you can see, I’m concerned about over driving/clipping the phono amp.

* Input sensitivity
64dB = 1.26mV
70dB = .63mV
34dB = 40mV
40dB = 20mV

1. Can you please help me understand how the input sensitivity of 1.26mV for the 64dB MC input relates to my Benz Ruby ZH with a roughly 1mV output.

What exactly should this mean to me?

After suffering 5 major strokes, my memory of many things have been lost. So, if anyone could please help me better understand how the above spec’s would affect me, I would truly appreciate it.

Best wishes,
Don

 

[SVS]

The numbers you provided indicate that the nominal output voltage of your preamp is 2 V, and the voltage at which clipping begins is 9 V. Your preamp will withstand an overload of 13 dB.
This is not much, but you can safely use your cartridge, especially if your LPs are not of poor quality.

 

[No Regrets]

Hello and thank you so much for your reply.

An overload margin of 13dB doesn't sound very reassuring to me.
My record collection is in pretty much all Near Mint condition.
I have normally read that you should strive for at least 20 dB of overload margin.
Should I be concerned that I would be overdriving/clipping the phono amp with only 13db of headroom?

I truly appreciate you trying to help me.

In case it is helpful, the phono amp that is under consideration is the Accuphase C-47. Here is a link to it's specification page that might show more information that might be helpful.

https://www.accuphase.com/cat/c-47_e.pdf

My plan was to use my Benz Ruby ZH that has roughly a 1mV output and 38 Ohm internal impedance.
The Accuphase does not use any step up transformers, it's just all gain from Jfets I believe.

I was hoping to use my 1mV cartridge into the 64dB gain MC input. However, my fear is that I will not have enough overload headroom.

I've been using my cartridge into my all tube phono amp that provides me with 62dB of gain without the use of any step up's or Jfets, etc and it has played beautifully. It sounds alive, and full bodied and has not been clipping my linestage or power amp.

When I use my 1mV cartridge with my other phono amps that have anywhere between 40 to 54dB, it tends to sound anemic and lifeless.

Do you or anyone have any additional thoughts?

Thank you and best wishes to you,
Don

 

[SVS]

Hi Don.

13 dB is the gain margin at 1.26 mV, for your 1 mV. this margin will be 15 dB.

If your LPs are in good condition, then they do not click when playing and you do not need 20 dB.

I looked at the review of your preamp, the electrolytic capacitors of its power supply have a maximum voltage of 25 V. Most likely, the supply voltage there is +/- 15 V, so it cannot provide a large overload capacity. For tube preamps with their supply voltage of several hundred Volts, this is not a problem.

You write about the sensitivity of the cartridge .1 mV. In this case, you have nothing to worry about at all. For it, the overload capacity is 35 dB.

Hello from Ukraine
Serhii.

 

[Salectric]

The Ruby ZH is sort of in no-man’s land. Its 0.7-1.0 mv output is low for a typical MM stage but rather high for most SUTs. I faced a somewhat similar situation years ago when I had a Glider M (0.8mv). Running the Glider directly into my MM input with 40db gain was just as you described—-rather anemic, lacking dynamics and energy. I ended up using a 1:10 SUT which restored dynamics and overall just sounded better. In your case, with the Ruby ZH having a rather high 38 ohm output impedance, maybe a 1:5 would be ideal.

 

[No Regrets]

You write about the sensitivity of the cartridge .1 mV. In this case, you have nothing to worry about at all. For it, the overload capacity is 35 dB.

Hello Serhii, Thank you for your reply... it is truly very much appreciated

I am so sorry, I see that I have mistyped earlier in some spots, stating that my cartridge had an output of .1mV (it actually is 1mV@5cm/sec).
I was typing using my iPhone at times and that doesn't work out for me all of the time with my big fingers . Please accept my most sincere apologies.
I don't know what the sensitivity of my cartridge is.
I do know that the output of my cartridge is roughly 1mV@5cm/sec.
I am very truly sorry for the confusion that I have just caused.
So, in light of my mis-typing, I would imagine that the overload capacity of 35dB is no longer an accurate number?

I looked at the review of your preamp, the electrolytic capacitors of its power supply have a maximum voltage of 25 V. Most likely, the supply voltage there is +/- 15 V, so it cannot provide a large overload capacity.

When you say above, that you looked at the review of my preamp... are you referring to the Accuphase C-47 phono amp that I am considering for purchase or are you talking about my vacuum tubed First Sound Presence Audio line stage that the Accuphase C-47 phono amp would be driving?

In case it might be helpful, here is a link to my vacuum tubed First Sound Presence Audio line stage: https://www.firstsoundaudio.com/technical

I appreciate having someone, like yourself, who knows how to decipher all of these technical details, helping me understand if the 64dB of gain from the Accuphase C-47 will be a good match for my 1mV cartridge.

Best wishes,
Don

 

[No Regrets]

I ended up using a 1:10 SUT which restored dynamics and overall just sounded better. In your case, with the Ruby ZH having a rather high 38 ohm output impedance, maybe a 1:5 would be ideal.

Hi!

I do have a very lovely sounding vintage Hirata Tango SUT that offers a 1:6.6 ratio; but I was hoping not to have to go that route. There are times when I get hum (and then other times when I do not). Probably sensitive with the placement. When it doesn't hum, it sounds amazing! I just don't want the added stress of whether or not it will hum and would rather just have a phono amp that will give 60-64dB of gain without having my 1mV cartridge overdrive it.

Best wishes,
Don

 

[SVS]

So, in light of my mis-typing, I would imagine that the overload capacity of 35dB is no longer an accurate number?

Yes, 35 dB is not our case.

 

[SVS]

When you say above, that you looked at the review of my preamp... are you referring to the Accuphase C-47 phono amp that I am considering for purchase or are you talking about my vacuum tubed First Sound Presence Audio line stage that the Accuphase C-47 phono amp would be driving?

I was referring to the RIAA preamp that you are asking about. I didn't know about your linear devices.

 

[SVS]

The Ruby ZH is sort of in no-man’s land. Its 0.7-1.0 mv output is low for a typical MM stage but rather high for most SUTs. I faced a somewhat similar situation years ago when I had a Glider M (0.8mv). Running the Glider directly into my MM input with 40db gain was just as you described—-rather anemic, lacking dynamics and energy. I ended up using a 1:10 SUT which restored dynamics and overall just sounded better. In your case, with the Ruby ZH having a rather high 38 ohm output impedance, maybe a 1:5 would be ideal.

Personally, I hear a deterioration in microdynamics when using MC transformers. Double conversion of signal energy from the cartridge (first from electric current to magnetic field, and then from magnetic field back to electric current) without loss is impossible, so problems with microdynamics occur.

Active MC signal amplifiers are used to eliminate this effect.

 

[hongkongfoufou]

Hello and thank you so much for your reply.

An overload margin of 13dB doesn't sound very reassuring to me.
My record collection is in pretty much all Near Mint condition.
I have normally read that you should strive for at least 20 dB of overload margin.
Should I be concerned that I would be overdriving/clipping the phono amp with only 13db of headroom?

I truly appreciate you trying to help me.

In case it is helpful, the phono amp that is under consideration is the Accuphase C-47. Here is a link to it's specification page that might show more information that might be helpful.

https://www.accuphase.com/cat/c-47_e.pdf

My plan was to use my Benz Ruby ZH that has roughly a 1mV output and 38 Ohm internal impedance.
The Accuphase does not use any step up transformers, it's just all gain from Jfets I believe.

I was hoping to use my .1mV cartridge into the 64dB gain MC input. However, my fear is that I will not have enough overload headroom.

I've been using my cartridge into my all tube phono amp that provides me with 62dB of gain without the use of any step up's or Jfets, etc and it has played beautifully. It sounds alive, and full bodied and has not been clipping my linestage or power amp.

When I use my .1mV cartridge with my other phono amps that have anywhere between 40 to 54dB, it tends to sound anemic and lifeless.

Do you or anyone have any additional thoughts?

Thank you and best wishes to you,
Don

Hello

I have the Accuphase C47.
I have connected a ZYX Ultimate 4D - 0.24 mV.
This is the cartridge I used.

ZYX Ultimate 4D-X MC Phono Cartridge

I don't need to use the option gain 70 dB.

If you have questions about C47, I can try to answer you.

All cartriges here are tested with Accuphase C47.

Khumar cartrige tested during 7 days and more....

What is this cartridge ? MC Khumar Cartridge is made in India with the Stylus:NUDE shibata III from JAPAN. This cartridge cost around 2500 US$ or 2300 Euros. Who has developed this cartridge? Tariq Shafeeque. Who is Tariq Shafeeque ? Tariq Shafeeque a structural engineer by profession is...

www.whatsbestforum.com

Regards

 

[hongkongfoufou]

I use with the C47 :
- Audio-Technica ART-9
- Nagaoka MP-500
- ZYX 4D (0.24 mV)
I wait the cartridge Khumar. It wiil arrive today.

I don't need to use gain 70dB.

I never try cartridge with 0.1 mV, so I can't answer you. Sorry.

 

[hongkongfoufou]

I have found this :

The Benz Micro RUBY ZH (high output) cartridge featured a gorgeous Zebra wood body, and the Micro Ridge stylus providing enhanced trackability, resolution and groove integrity. The ZH at .7mV, is ideal for tube phono stages in the 50-60dB gain range.

Specifications​

• Output Voltage (3.54 Cm/sec): 0.7 mV
• Stylus Shape: Micro Ridge
• Stylus : 5 x 120µm
• Internal Ohms: 38
• Loading Range: >400 ohms
• Weight: 10.2 grams
• Compliance: 15cu
• Tracking: 1.8-2 grams


With the Accuphase C47, gain 70 dB, it is written 0.63 mV...

 

[SVS]

I have found this :

The Benz Micro RUBY ZH (high output) cartridge featured a gorgeous Zebra wood body, and the Micro Ridge stylus providing enhanced trackability, resolution and groove integrity. The ZH at .7mV, is ideal for tube phono stages in the 50-60dB gain range.

The key word is "tube." In our case, a solid-state device.

 

[hongkongfoufou]

The key word is "tube." In our case, a solid-state device.

Yes, I have seen that.
70 dB for the Accuphace C47...

 

[hongkongfoufou]

The Benz Micro Ruby-Z features a new zebrawood body, second only to ebony for its resonance characteristics, offering weight and definition in the bass, linearity in the midrange, and clarity in the high frequencies with natural musicality.

The Benz Micro Ruby-Z's new MicroRidge stylus is in place and offers improved tracking, resolution, and groove integrity. The generator is based on the Ruby square plate and is available in .35 mV and .7 mV outputs (Benz Micro Ruby-ZH). The low output of the Benz Micro Ruby-Z is best used with phono stages offering a gain of more than 60 dB, loaded with 400 ohms or more.

 

[No Regrets]

Yes, 35 dB is not our case.

So, because we are using a 1mV cartridge (instead of a .1mV which I had mis-typed earlier) does that mean we are back to having an overload margin 15dB?

 

[No Regrets]

If you have questions about C47, I can try to answer you.

Hello and thank you for your message!

I appreciate you giving me the additional data points regarding some of the cartridges that you have used with the C-47.
I will likely send you a private message asking you more about the C-47.

Thank you so much!
Don

 

[No Regrets]

I never try cartridge with 0.1 mV, so I can't answer you. Sorry.

Hello and thank you for your post!

Sadly, with some of my posts above I was typing them using my iPhone and mistakenly typed ".1mV" when I had actually meant to type "1mV" for the output of my cartridge, the Benz Ruby ZH.

I am truly sorry for the confusion that I have caused.. especially to Serhii who has been so kind to put in so much time and effort into sharing what the technical specifications might mean when using my cartridge.

Best wishes to you all,
Don

 

[No Regrets]

I have found this :

The Benz Micro RUBY ZH (high output) cartridge featured a gorgeous Zebra wood body, and the Micro Ridge stylus providing enhanced trackability, resolution and groove integrity. The ZH at .7mV, is ideal for tube phono stages in the 50-60dB gain range.

Specifications​

• Output Voltage (3.54 Cm/sec): 0.7 mV
• Stylus Shape: Micro Ridge
• Stylus : 5 x 120µm
• Internal Ohms: 38
• Loading Range: >400 ohms
• Weight: 10.2 grams
• Compliance: 15cu
• Tracking: 1.8-2 grams


With the Accuphase C47, gain 70 dB, it is written 0.63 mV...

Yes, this is my cartrdge
They list the output as .7mV@3.54cm/sec; which I believe equates to roughly 1mV@5cm/sec.
Thank you for posting this for me!

Best wishes,
Don