|
Cardas Frequency Sweep and Burn-In Record
The "Sweeper", in addition to the standard tones, includes relative and absolute polarity checks, vocal channel identification and frequency sweeps that ultrasonically clean the cartridge stylus and degauss the entire system. And, locked, pink noise grooves that repeat endlessly, blank plateaus, even a sync label to check platter speed. All on a 180 gram pressing with a smiling Stan cover.
General Suggestions for Use by George Cardas The Cardas Frequency Sweep and Burn-In Record is a set of tools that audiophiles have requested over the years. The benefits and uses of the "Sweeper" vary because turn tables and systems differ, as does the knowledge and tools of the end user.
The most important tools on this record are the Side 1 Frequency Sweeps. These are the degaussing tracks 2a, 2b and 2c. Simply play one of these tracks through your system at a low, normal level and it will degauss the cartridge and the rest of the system, plus clean the stylus ultrasonically. When played, the tracks progress from low frequencies at a high relative amplitude, to high frequencies (35 k+ if played at 45 rpm) at a low level. This is a complete degaussing process and an ultrasonic cleaning of the stylus at the same time. You may hear clicks and pops in the high frequency section after use. This is caused by the accumulation of junk which has fallen off the stylus during ultrasonic cleaning. Clean the record to remove the debris. This is the most efficient and cheapest way I know to degauss your cartridge and system. Basically, it makes a flux buster obsolete.
How often you use the Frequency sweeps is something you have to determine for yourself. The build up of residual stress in a system, is system dependent. Some parts require more frequent degaussing than others. For instance, permeable parts require more frequent degaussing than non permeable parts. An iron core cartridge will need more attention than ruby cored cartridge. Speakers with cored inductors acquire more stress than those with air core inductors. There should be an audible difference after you play the Frequency Sweeps. I run the sweeper at least once a week, it really works!
The sweeps are also useful as room tuning tools for setting up wall and ceiling treatments. Room reflection points, as well as other anomalies in the system, cause the image to shift with rising frequency. Simply sit in the hot spot and play the sweep at a low level. The image should be centered and stable in a well focused room. You can ignore changes in volume which are caused by comb filtering. Hard reflection points in the room can cause a shifting in focus, so padding these points will help stabilize the image. Hold a piece of foam rubber at arms length and block the sound from suspected reflecting points. When you think you have located the trouble spots, cover them with suitable damping materials.
An interesting speaker set-up trick is to listen to the low frequency, out of phase tones while sitting in the listening position. The note should cancel completely if speakers are positioned symmetrically. Try both tones and pick the one that works best for your room. Playing this tone while in the null point, at the hot spot, may also allow you to pick out strange noises and rattles in the system. Sorting out the exact cause of these anomalies is up to you.
|