A question about digital dynamic range, line levels and volume control....

GregH2 · 6th February 2010, 09:30 AM

Hello all,

I have a question about how to get the best sound out of my system, but firstly let me outline my setup. I primarily use itunes as my music library, with lossless audio. Using itunes I stream audio to an apple airport express, the digital output of which is connected to my Benchmark DAC-1. The DAC then feeds my gainclone.

Now, I have two ways of controlling the volume. I can either set the volume on the DAC to a fixed level and alter the volume digitally in itunes before streaming to the airport, or set the itunes volume to a fixed level and alter the volume using the analog DAC volume knob. My question is, which method is best? This may seem like a silly question, but I suspect (with complete ignorance regarding how D/A conversion works), that using a lower volume setting in itunes provides the DAC with a digital signal of lower dynamic range, an unfavourable scenario. In this case the analogue volume control would be preferable. Is this understanding correct, or does the volume in itunes have nothing whatsoever to do with the bandwidth of the signal provided to the DAC?

I would prefer to use the volume control in itunes as there are no mechanical parts to wear out and it is more convenient. However, I suspect that it is better to set the volume on the analogue side. I _think_ my listening tests have verified this.

What are your thoughts? I appreciate your comments.

Regards,

Greg.

sakis · 6th February 2010, 09:39 AM

its a reasonable question and in a few words the second way is better that will provide a better S/N ratio but this is also depenting on the input impedance of your amplifier and the resistance of the analog potentiometer

again in a few words if the input impedance of your amplifier is above 22K ( or 50K that would be the optimum ) and the potentiometer you have is 100K then yes this is the best combination from all

regards sakis

( carefull listening of your favourite tune will prove the above right ...use your favourite tune and trust your ears )

GregH2 · 7th February 2010, 03:35 AM

OK, great. Thanks for your reply. That is what I suspected.

Greg.

6th February 2010, 09:30 AM	#1
GregH2 diyAudio Member Join Date: Oct 2009	A question about digital dynamic range, line levels and volume control.... Hello all, I have a question about how to get the best sound out of my system, but firstly let me outline my setup. I primarily use itunes as my music library, with lossless audio. Using itunes I stream audio to an apple airport express, the digital output of which is connected to my Benchmark DAC-1. The DAC then feeds my gainclone. Now, I have two ways of controlling the volume. I can either set the volume on the DAC to a fixed level and alter the volume digitally in itunes before streaming to the airport, or set the itunes volume to a fixed level and alter the volume using the analog DAC volume knob. My question is, which method is best? This may seem like a silly question, but I suspect (with complete ignorance regarding how D/A conversion works), that using a lower volume setting in itunes provides the DAC with a digital signal of lower dynamic range, an unfavourable scenario. In this case the analogue volume control would be preferable. Is this understanding correct, or does the volume in itunes have nothing whatsoever to do with the bandwidth of the signal provided to the DAC? I would prefer to use the volume control in itunes as there are no mechanical parts to wear out and it is more convenient. However, I suspect that it is better to set the volume on the analogue side. I _think_ my listening tests have verified this. What are your thoughts? I appreciate your comments. Regards, Greg.

6th February 2010, 09:39 AM	#2
sakis diyAudio Member Join Date: Jan 2006 Location: nea makri athens greece	its a reasonable question and in a few words the second way is better that will provide a better S/N ratio but this is also depenting on the input impedance of your amplifier and the resistance of the analog potentiometer again in a few words if the input impedance of your amplifier is above 22K ( or 50K that would be the optimum ) and the potentiometer you have is 100K then yes this is the best combination from all regards sakis ( carefull listening of your favourite tune will prove the above right ...use your favourite tune and trust your ears ) __________________ SERVICE ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr

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
digital volume control	aardvarkash10	Tubes / Valves	11	10th December 2008 02:41 PM
lesser of two evils, high level -> line level, digital volume control	mazurek	Solid State	3	19th November 2006 12:25 AM
Quantization Levels and Dynamic Range	percy	Digital Source	29	22nd May 2006 06:11 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

7th February 2010, 03:35 AM	#3
GregH2 diyAudio Member Join Date: Oct 2009	OK, great. Thanks for your reply. That is what I suspected. Greg.

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