How much db gain is needed for 0.55mV output MC cartridge

Sunsun22 · 9th November 2009, 12:37 PM

I have had a phono amp which was very clear on DIP setting on cartridge output in mV. Recently, I changed to a new phono amp that only stays XX db gain on soldering a feedback resistor. My cartridge is 0.55mV output, how much db gain I needed? Thanks

richie00boy · 9th November 2009, 12:43 PM

What output voltage do you need?

Sunsun22 · 9th November 2009, 01:04 PM

I need 2.5V RMS for my preamp.

atarashi · 9th November 2009, 01:36 PM

Well, if you really need such a high output voltage, you would need 73dB Gain.
20*log(2.5/0.00055)

Michael

Sunsun22 · 9th November 2009, 01:51 PM

Actually I don't know. What is a normal voltage to drive a preamp?

PigletsDad · 9th November 2009, 02:29 PM

The difficulty with levels is because CD sources are rated by maximum output level (typically 2Vrms), while vinyl levels are at nominal values, corresponding to 5cm/s stylus velocity. Most cartridges can track much more than this; in the treble range some can do well over 50cm/s, corresponding to peaks that are 20dB above nominal.

In my system, 0.5V nominal output from the phono stage is a convenient value, but it obviously depends on the whole system. With 0.55mV source, this is close enough to 60dB of gain.

atarashi · 10th November 2009, 01:11 PM

What is the Gain of your Preamp?

But PigletsDad's guess with 60dB might be a good start...

peranders · 10th November 2009, 01:22 PM

Quote:

Originally Posted by Sunsun22

I have had a phono amp which was very clear on DIP setting on cartridge output in mV. Recently, I changed to a new phono amp that only stays XX db gain on soldering a feedback resistor. My cartridge is 0.55mV output, how much db gain I needed? Thanks

2.5 Vrms sounds much as output voltage. The best thing you could do is actually listen and adjust according to that.

SoNic_real_one · 10th November 2009, 01:32 PM

The analog "Line" input of the amplifiers is calibrated nominaly to 0dBu at 0.775mVrms. The "CD" analog input should be calibrated to +4dBu to admit a nominal 1.23Vrms.

9th November 2009, 12:37 PM	#1
Sunsun22 diyAudio Member Join Date: Jul 2004 Location: Hong Kong	How much db gain is needed for 0.55mV output MC cartridge I have had a phono amp which was very clear on DIP setting on cartridge output in mV. Recently, I changed to a new phono amp that only stays XX db gain on soldering a feedback resistor. My cartridge is 0.55mV output, how much db gain I needed? Thanks

9th November 2009, 12:43 PM	#2
richie00boy Did it Himself diyAudio Member Join Date: Nov 2003 Location: Gloucestershire, England, UK	What output voltage do you need? __________________ www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Increasing Low Signal Output cartridge using Nakamichi Dragon.	longaniza	Analogue Source	2	27th September 2007 02:23 PM
more gain needed -> how?	Danko	Tubes / Valves	26	18th January 2006 04:13 PM
WTB: defective low output MC cartridge	ghg	Swap Meet	0	28th July 2005 09:37 AM
HELP! High gain, low noise fet advice needed!	Lenin	Swap Meet	17	21st February 2002 01:08 PM
Help! High gain, low noise fet advice needed!	Lenin	Solid State	1	16th February 2002 02:53 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

9th November 2009, 01:04 PM	#3
Sunsun22 diyAudio Member Join Date: Jul 2004 Location: Hong Kong	I need 2.5V RMS for my preamp.

9th November 2009, 01:36 PM	#4
atarashi diyAudio Member Join Date: Jun 2005 Location: Vienna	Well, if you really need such a high output voltage, you would need 73dB Gain. 20*log(2.5/0.00055) Michael

9th November 2009, 01:51 PM	#5
Sunsun22 diyAudio Member Join Date: Jul 2004 Location: Hong Kong	Actually I don't know. What is a normal voltage to drive a preamp?

9th November 2009, 02:29 PM	#6
PigletsDad diyAudio Member Join Date: Jul 2007 Location: South Worcestershire	The difficulty with levels is because CD sources are rated by maximum output level (typically 2Vrms), while vinyl levels are at nominal values, corresponding to 5cm/s stylus velocity. Most cartridges can track much more than this; in the treble range some can do well over 50cm/s, corresponding to peaks that are 20dB above nominal. In my system, 0.5V nominal output from the phono stage is a convenient value, but it obviously depends on the whole system. With 0.55mV source, this is close enough to 60dB of gain.

10th November 2009, 01:11 PM	#7
atarashi diyAudio Member Join Date: Jun 2005 Location: Vienna	What is the Gain of your Preamp? But PigletsDad's guess with 60dB might be a good start...

10th November 2009, 01:32 PM	#9
SoNic_real_one diyAudio Member Join Date: Jan 2008 Location: Virginia	The analog "Line" input of the amplifiers is calibrated nominaly to 0dBu at 0.775mVrms. The "CD" analog input should be calibrated to +4dBu to admit a nominal 1.23Vrms.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)