Sunday Feb 18

I Remember Mono

I'm getting the odd impression that monaural sound has become cool.  I mean no disrespect toward the first 75 years or so of recorded sound.  Mono itself isn't odd.  Recent developments surrounding it are.

Certainly one of the oddest is the new Helikon mono phono cartridge--designed, priced, and promoted to attract the attention of the well-heeled audiophilia nervosa crowd.  I'm certain that it's well built and carefully designed, but ultimately its goal is to do for $2000 a marvelous job that could be done exceedingly well for about $2 in the form of a mono/stereo switch on a phono stage.  It's a rare manufacturer who is willing to take that simple, obvious, beneficial, and inexpensive step.  It's probably easier to sell an expensive mono cartridge than to promote an switch on a phono stage.  So we'll probably see more more mono cartridges with three and four figure price tags before we see the switches.

Happily, adding a stereo/mono switch to a phono stage is an easy do-it-yourself project.  Pick up a toggle switch at Radio Shack or other electronic parts outlet, drill an appropriate hole somewhere in the enclosure of the phono stage, and run jumpers from the Left and Right signal inputs to the switch so that they will connect together when you throw the toggle.

This will instantly clean up any extraneous "stereo" noise on your mono LPs, 45s, and 78s.  It will also instantly void any manufacturer's warranty.

Such a switch will, of course, work only for phono playback.  That's the most important place to have that function available, but being able to combine left and right channels can be useful on occasion for other inputs.  For instance, I've come upon a few CDs that were dubbed directly from mono LPs without paralleling the channels.  To listen those CDs properly, I switch to mono mode (yes, my control preamp has such a switch) and correct the mastering engineer's oversight.

Tuners may benefit from manual mono switching, too, like when automated stereo control doesn't revert to mono mode soon enough on a weak stereo signal.

To mono out the channels on a receiver, preamp, or amplifier on all inputs you can put a jumper across unit's left and right tape outputs.  You do that by simply plugging one end of a single audio cable into the left tape out jack and the other end into the right. [2009.12 UPDATE:  I recently tried this with an integrated amplifier that had two tape loops and a front panel selector switch with a multiplicity of monitoring, dubbing, recording, and playback options.  In this case the simple jumper cable expedient described above failed to combine the channels.  I worked out a fairly simple hardware "mono-izer" project which I'll pass along.]

It's a bit of a bother to do very often and you must always remember to remove the jumper for normal stereo listening.  So you might consider installing an external switch.  Wire it into the cable so you can break the left-to-right connection while leaving the cable in place. You could put the switch in a small project box to fancy it up a bit or just tape it to the cable.  This cable solution--with or without the convenience switch--will deal with all inputs.  Do the monoing this way and you would not need an additional mono switch for the phono input.

Remember:  Whatever mono method you use, be sure to put things back to stereo mode when you want to listen to stereo recordings or stereo FM.  And that brings up another odd mono matter.

In the past couple of years I've often thought I'd forgotten to switch the system back to stereo when listening to a new CD.  But when I walked over to the preamp to throw the switch, I'd find that it wasn't in mono mode at all.  The music had been recorded without much stereo information.

I confirmed this by using the switches on my preamp that let me listen to left channel only through both speakers or right channel only.  Switching between those would disclose practically no difference between the stereo channels.  In fact, running the gamut from Stereo to Mono to Left only to Right only often produces minimal changes in listening experience.

In the early days of stereo recording, the ability to separate channels was regularly used to excess.  Crazed engineers and producers would record hard left and hard right signals, leaving a hole in the middle of the soundstage.  These days crazed engineers and producers do nothing but fill that hole in the middle and ignore the fact that they have two discrete channels to work with.

And that makes me wonder.  With the arrival of SACD, DVD-Audio, and Blu-Ray we've been suddenly given a multiplicity of channels.  If we've forgotten how to use two, what are we going to do with four or six?