Greg Weaver

December 1997

with Greg Weaver

Part VI
A Fist Full of Freebies

This month I'm taking a break, well more like a sabbatical, from the software treatment route in an effort to bring to you some other things that will help you get a little closer to Musical Truth (See Todd Warnke’s excellent review of the Dunlavy SC-III). Don't worry, I'll be bringing you treatment’s San, Shi and Go (about using Dr. Goldman’s Miracle Record Cleaner, CD Clarifying, and the use of the CD Backlight, respectively) in future installments. This month though, I have a handful of freebies that I have been urged to share by some close friends who feel these are highly significant. The common factor for these particular tweeks is that they are all FREE!

FREEBIE NUMBER ONE - LISTEN AFTER 9:00 P.M. One of the major causes of irretrievable losses to your music system’s ability to resolve things like silence, quiet passages, staging, imaging, fine definition of timbre and harmonic structure, is the state, or the condition, of the power being delivered to your components from that socket on the wall.

Your electric utility company has a term for times of heavy demand on your local power supply grid. That term is Peak Usage. During peak usage times, excessive demands on power consumption by both industry and the residential sector cause drastic spikes, surges, disruptions and can even be responsible for voltage variations and fluctuations. In my area, peak usage times are daily from about 8:00 to 11:00 a.m. and then again from about 4:00 to 7:00 p.m. These are the times when people are typically using "heavy" appliances like their washing machines, dishwashers, cloths dryers which utilize large motors and/or heating elements. When the motors in these devices kick on, the resultant surges required to overcome momentum and start the induction motor turning causes uneven demands on the current. There is even a back flush of electro-motive force from the motor’s primary coil applied to your A/C line during these start ups which further complicate the issue. Most of you are aware that devices which have heating elements draw massive current. Just watch your lights dim when you first switch on a hair dryer or cloths iron. If a device incorporating a heating element also involves the use a motor, it compounds the issue yet further.

If you live in an industrial area, your peak times will probably be very different. In fact, the peak usage times vary widely from season to season. Spring and autumn offer typically lighter usage than summer and winter when air conditioners and heaters are in use. A call to you local utility company will provide you with the actual peak times for your area.

I wonder, have you ever noticed that your system sounded better late one evening when you played that new CD just before bedtime? If you did but ignored it, you were missing out on a great thing. Why do you think so many people use power-conditioning devices?

Such devices typically smooth out any spikes and dips and filter out the grunge common during heavy power demands and thereby help to regulate the A/C that your equipment sees. If you have ever thought such accessories to be simply "smoke and mirrors," you may now come to understand why they are so popular. They can typically provide you with the same conditions you have available from your outlets at say, 10:00 p.m., all day long. This is not a blanket recommendation for all devices which "condition" your A/C. Unfortunately, just like any other component, their usefulness varies from one to another, just as does the performance of other components. Listen before you buy.

Listening on Monday morning reveals a very different sounding system from the one you hear Wednesday night after the early news. So much so, it almost sounds like a different system. Typically your will find a better resolution of the quiet sections of recordings. Imaging and soundstaging become more focused and stable. Timbre is rendered more truthfully, as are the harmonics of the system. Give it a try. You just might find yourself making more time to listen later in the day.

You can take even more extreme measures to help "stabilize" your power whenever you choose to listen. I have installed a switch on my refrigerator for just such reason. That, and the fact that it is a mere dozen feet from my listening chair! I go so far as to shut off all my digital components, like my D to A converter and computer, during critical listening. I even turn off my heat or air conditioning to avoid unwanted fluctuations in the A/C delivery, as well as to remove extraneous background noises. Turning all these things off removes a form of "hash" from the over all sound of my system. These tactics are so effective that Pierre Sprey, the gifted engineer and founder of Mapleshade Productions, does the same things when he is making a recording. Nearly all of his recordings are made late night/early morning and all his appliances and computers are shut down during the process.

Listening late at night, after 10:30 p.m., is the common state of affairs at Casa Weaver, as that is when my significant other leaves for work (she works the overnight shift at a local nursing home). I typically kick-start the old reference system about 9:00 p.m. and start listening as she heads out the door at 10:30 p.m. Which brings us to ....

FREEBIE NUMBER TWO - TURN YOUR EQUIPMENT ON AN HOUR BEFORE YOU PLAN TO LISTEN. Electronic equipment, especially amplifiers, sound better after they have reached their normal operating temperature and had time to stabilize thermally. Since most amplifiers use some form of thermal bias tracking, the bias system does not stabilize until the thermal equilibrium is reached. Thermal equilibrium is dependent on the thermal mass of the amp, which is in turn determined by the amount of heat sink area and other solid mass used to dissipate the heat generated by the output devices. The larger the thermal mass, the longer the amp takes to warm up and stabilize. Current in the circuit is in a state of constant fluctuation until the bias settles.

Also, the output semiconductors or tubes change operating characteristics as they heat. In some amps, ones that do not use thermal tracking bias systems, the bias point is reached much faster. However, due to the thermal mass of the amp, it still requires time for the semiconductors or tubes to reach operating temperature. Once your system is stable, the sound is consistent and the best it can be. The results of this "warm up" time expresses itself as purer timbre, richer harmonics and more stable images. These effects are usually achieved within an hour.

Although I’ve been describing this attribute as specific to amplifiers, all electronics adhere to this physical law. So turn on your pre amp, CD player, tuner, cassette deck or whatever source and ancillary equipment you intend to use during your listening. Once again, listen and hear it for yourself.

FREEBIE NUMBER THREE - TURN ALL YOUR KNOBS ONCE A WEEK. Leaving your volume control, or any other control on your pre amp, receiver or amplifier for that matter, in the same position all the time contributes to the degradation of your system's sonic performance. It allows for oxidation to build up on the potentiometer's wipers. This creates a higher resistance to the small signal transfer at this point and results in restricted signal transfer. In sever cases, it can cause intermittent channel drop out and/or noisy performance. I’m sure you have run across an old receiver somewhere that crackles and pops as you turn the volume knob. This situation is easy to avoid. Just run all the control knobs full deflection once a week or so. The natural action the wiper takes on the tracks is not unlike sanding the contacts in an effort to keep them from oxidizing.

FREEBIE NUMBER FOUR - MAKE SURE YOUR SPEAKERS ARE SYMMETRICALLY PLACED AND LEVEL. After all the time you’ve taken to make sure the placement was just right, don’t forget to finish the job. Use a measuring tape to be sure both speakers are equally spaced from the rear and side walls. Be sure that you measure from the middle of the tweeter or woofer, not the back of the cabinet or, worse yet, the bottom corner of the cabinet (or the speaker stand with bookshelf speakers). Then apply the use of a small level, available at any home improvement or department store for just a few bucks, and LEVEL the speakers. You can use the leveling spikes provided with your floor standing speakers or speaker stands. If leveling spikes are not provided, use coins or washers to shim them back to true. Don’t use matchbooks or folded paper, as those items tend to change their thickness over time.

Take your measurements again to make sure the drivers are still equal distances from the rear and side walls, and then re-level them if necessary. This may sound a bit anal, but until you’ve done it, you won’t believe what it will do for the soundstaging and imaging properties of your system. I was about ready to give up on getting the famous magical soundstage from my eight-foot tall electrostatic panels many years ago when I noticed that the tops of the panels were leaning different directions. A closer examination revealed this to be so because they were not level. Even though the bases were perfectly placed, because my floor wasn’t perfectly level, the difference at the top of the panels was nearly three inches! Shimming and re-measuring took a good sounding system over that fabled hill into Nirvana.

...Greg Weaver
gregw@soundstage.com