Kirmuss Audio KA-RC-1 Ultimate Ultrasonic Vinyl Restoration System

It Works With Time and Patience

Equipment report
Record-cleaning machines
Kirmuss Audio KA-RC-1 Ultimate Ultrasonic Vinyl Restoration System

The owner’s manual warns against keeping water in the ultrasonic washer tank overnight. The unit has to be drained and cleaned at the end of the day after each restoration session. The process includes draining the water from the tank, wiping the tank with the 70% isopropyl alcohol-damped Rabbit cloth, removing the felt assemblies from the record washer slots, rinsing them with a light mist of distilled water, patting them dry with the Rabbit cloth, and then letting them air dry before reinserting them into the record washer assembly. The user must also rinse the underside of the record washer assembly and use the Rabbit cloth to dry it. The water may be drained from the unit and returned to the original containers, but must be used within one day (or a maximum of 15 records) to prevent fungus from growing in it. 


The KA-RC-1 system is unlike other record cleaners. There are many steps and decisions to be made in the groove restoration process that require user engagement during the hands-on process. Several 12" records were given the Kirmuss restoration treatment. In all but one case, the 4-to-5 five-minute process was used—only one 2-LP used record boxset required the 5-to-6 two-minute cycles. 

One of the notes in the KA-RC-1 owner’s manual informs the user to quit using the unit after 35 minutes of nonstop operation to allow a 10 minute cool-down (the top cover is removed for this cool-down). In one instance, on an autumn day, the temperature monitor moved to the high temperature mode during a multiple LP cleaning session. When this occurred, the temperature inside the room was near 76 degrees. The cool-down process listed in the owner’s manual requires removing the top cover and letting the water temperature decrease until the monitor bar shows an acceptable color. This is said to take 10–15 minutes. The cool-down on this autumn day required a little more time than specified—closer to 20 minutes. After that cool-down, the restoration process continued without further issue. 

Because of the ultrasonic cavitation heats the water, the parts of the records immersed in the water will thermally expand as they do with other cleaning units (this is normal thermodynamics), while the portion of the record in the air will want to retract to normal. The result is a slight bit of expansion and retraction visible during the cleaning process as a mild warp. When the record is removed and reaches room temperature, it returns to its normal state.

When compared to other methods used to clean records, the KA-RC-1 system yielded results that ranged from no sonic changes to a more open sound. In one case, an album of Mahler’s Fifth produced a much more spacious sound with excellent instrumental timbre. The entire soundstage was more clearly audible to the point of near-supernatural reproduction of instrument placement. However, this same performance lost a noticeable amount of initial transient information. Moreover, upon removal of the album from the turntable, the cartridge contained a healthy amount of white crud pulled from the grooves. The KA-RC-1 owner’s manual points out that when this happens, the record needs to go through another cleaning process. This LP met the criteria for completing the first round of the two-minute cycles. Even though this record didn’t produce any toothpaste material during the second round of 5-to-6 two-minute cycles, the entire process was applied a second time. Upon playing the record, the white crud showed up again. Instead of doing a third set of two-minute cycles, the album was subjected to a single five-minute final cycle without any of the anti-bacterial/anti-static solution added. After this replay there was zero white crud from the grooves. In addition, the initial transient information missing prior to the final extended five-minute ultrasonic wash was restored. Subjectively, it appears the final cycle needs to be longer than two minutes when that cleaning cycle is used. Perhaps the manufacturer can shed some light on this observation. It should be noted, that this was specific only to the multiple two-minute cycle process. Finally, note that the stylus profile used to play the restored records (line-contact) falls into the high-precision category (along with micro-ridge, microline, and Shibata) that provides more intimate contact with the groove walls.

At an affordable price of $970 for a restoration system that incorporates ultrasonic cleaning, the KA-RC-1 gave expected audible results when a record was “cleaned.” The process worked with some reservations. The first reservation (the accumulation of toothpaste-like goop on the stylus) was lessened with a longer final five-minute ultrasonic cleaning cycle after the multiple two-minute processes. The second reservation is allocating the time it takes to complete the restoration process along with the necessary preparation and cleanup. For those of us with busy schedules, a dedicated day may be required to utilize (and maximize) the KA-RC-1 restoration process when cleaning multiple records. With each record requiring several minutes to process (only two 12" records can be ultrasonically cleaned at one time—three 12" records with the model made for Upscale Audio), inclusive of the initial 5-minute start cycle to polishing finish, a certain level dedication is required to use the Kirmuss. If you can devote the time and energy needed to get the best of this restoration process, you should seek out a demo and give the KA-RC-1 vinyl restoration system a try. It works, if you have the time and patience to use it properly.

Specs & Pricing

Type: Ultrasonic record cleaning system
Dimensions: 21.3" x 13.3" x 10.9"
Weight: 21.6 lbs.
Price: $970

51 West 84th Ave., Suite 301
Denver, Colorado 80260
(303) 263-6353