George J
Herefordshire member
Dear marshamp,
I have been using mono for about five years from digital via firstly a Naim DAC V1 and for the last three years with an Audiolab MDAC.
The digital source for the MDAC is a Mac mini running iTunes [uncompressed AIFF files from CDs] and the MAC offers a satisfactory method of combining the two channels of stereo to mono [Accessibility preferences -> Audio -> Play stereo audio as mono] at the digital stage prior to conversion to analogue. Obviously the mono emerges at the MDAC as dual mono [ie. both output RCA sockets are the same mono signal], and what I do is feed one of these to the Quad II Forty and the other to the input of a headphone amp, so as to give a dummy load to the the MDAC on the redundant channel.
The issue of mono compatibility [in a stereo recording] is important to consider. Most classical recordings - being recordings of natural un-amplified instruments actually recorded in ensemble in a real hall - are mono compatible. The point is about phase coherence between the two stereo channels. For non-compatible recordings the conversion process can produce a comb-filter effect that really is odd. However for the tiny number that I have which don't convert to mono well, I can listen to the left channel alone of the stereo ... This works well enough, albeit that the information in the right channel is lost and the right side of the orchestra will be further back in the balance ... Not ideal, but fortunately for me most of these non-compatible [with mono summing] recordings were made in the 1970s [in the short lived era of ultra multichannel recordings and a huge number of spot microphones] at a time when none of my favourite musicians were active in the studios.
Obviously the Troughline being a completely mono tuner, it is a question of a single channel source feeding a single channel amplifier and speaker. Very simple approach.
A sidelight on stereo recording in the 1950s and 1960s is that the recordings were most often issued in mono pressings as well as stereo. More recent recordings from the 1980s onward tend to be true compatible stereo as the fashion for a simple microphone array came back into favour.
I hope that helps a little.
With best wishes, George
PS: I don't use any further digital signal processing. Just AIFF and combined at the digital stage to dual mono - most classical recording is well enough done to work well without the need for manipulation of the EQ beyond what is issued on the CD.
I have been using mono for about five years from digital via firstly a Naim DAC V1 and for the last three years with an Audiolab MDAC.
The digital source for the MDAC is a Mac mini running iTunes [uncompressed AIFF files from CDs] and the MAC offers a satisfactory method of combining the two channels of stereo to mono [Accessibility preferences -> Audio -> Play stereo audio as mono] at the digital stage prior to conversion to analogue. Obviously the mono emerges at the MDAC as dual mono [ie. both output RCA sockets are the same mono signal], and what I do is feed one of these to the Quad II Forty and the other to the input of a headphone amp, so as to give a dummy load to the the MDAC on the redundant channel.
The issue of mono compatibility [in a stereo recording] is important to consider. Most classical recordings - being recordings of natural un-amplified instruments actually recorded in ensemble in a real hall - are mono compatible. The point is about phase coherence between the two stereo channels. For non-compatible recordings the conversion process can produce a comb-filter effect that really is odd. However for the tiny number that I have which don't convert to mono well, I can listen to the left channel alone of the stereo ... This works well enough, albeit that the information in the right channel is lost and the right side of the orchestra will be further back in the balance ... Not ideal, but fortunately for me most of these non-compatible [with mono summing] recordings were made in the 1970s [in the short lived era of ultra multichannel recordings and a huge number of spot microphones] at a time when none of my favourite musicians were active in the studios.
Obviously the Troughline being a completely mono tuner, it is a question of a single channel source feeding a single channel amplifier and speaker. Very simple approach.
A sidelight on stereo recording in the 1950s and 1960s is that the recordings were most often issued in mono pressings as well as stereo. More recent recordings from the 1980s onward tend to be true compatible stereo as the fashion for a simple microphone array came back into favour.
I hope that helps a little.
With best wishes, George
PS: I don't use any further digital signal processing. Just AIFF and combined at the digital stage to dual mono - most classical recording is well enough done to work well without the need for manipulation of the EQ beyond what is issued on the CD.
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