Old Pa
Headphoneus Supremus
- Joined
- Dec 9, 2001
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Ah!’s Njoe Tjoeb CD players have now gone through several iterations. Basically, the Dutch makers take a production Magnavox CD player and then modify it with improved transformers, socketed solid state digital stage, tubed analog, and a variety of user selectable improvements like feet and power cords. Virtually everything can be changed and played with to the owner’s heart’s content. Upscaleaudio.com has posted the report of Neville Roberts, a Brit who has played extensively with these modifications. His report is recommended reading and will not be duplicated here.
My Super Njoe Tjoeb 4000 is tricked out with the improved power cord, de-coupling feet, tube “ribs”, optional 24/192 upsampler, etc., but its Magnavox case, made of lighter metal than most Band-Aid boxes, seemed a sonic limitation begging to be addressed. Mr. Roberts approached the problem with a thin self-adhesive sheet of asphalt-based automotive sound deadening material stuck on the inside of the upper lid and reported good result. I, of course, had to make more of a mountain out of this particular molehill.
Parts Express (.com) catalogues an assortment of automotive sound dampening products aimed at those who participate in car stereo competitions. I don’t know much about these contests, but competition generally improves the breed, and it’s nice to have someone else pay for the R&D. My $20 bought me a 10”x13” lightweight vinyl sound dampening sheet (#268-030) and a 20oz can of Cascade VB-1S Pro Quiet Damping spray (#268-250).
Originally, I had planned to stick the 10”x13” vinyl sheet up on the inside of the Njoe Tjoeb’s thin metal upper case and then slather it with the sound deadening spray. After a little cranial percolation upon receiving and examining the damping products and their instructions, my plans changed. Instead, I pressed the vinyl sheet to the bottom of the unit between the feet (fits perfectly and can be pressed onto the plastic connectors that extend from the inside of the case) While the lower case upon which the “works” are mounted is of heavier gauge than the top case, it, too, needed some sound and resonance damping.
The inside of the upper case was first cleaned and degreased for best adhesion of the Cascade sound damping spray. This was accomplished using common spray household cleaner followed by window cleaner followed by denatured alcohol. Surface prep always pays off.
It took some time to mask the inside of the upper case to prevent overspray from interfering with refitting the upper case on the lower case. The Cascade VB-1S instructions indicated the product was to be applied warm (70-75F) and kept warm during curing and that no more than 1/32” thickness should be applied per spray coat. Warming the product in a bucket of warm water (as per label recommendations) also produced some impressive spray pressures. I got splatter up to 18” from the work surface. In retrospect, I should have masked at least the outside sides of the case as well. As it was Cascade recommends toluene as a solvent and I substituted Hoppe’s No. 9 to clean up the overspray.
Two coats of the Cascade Pro Quiet were applied with two hours drying time in between coats. Final coat was dried for an hour inside the house and in the sun and then an hour in a 120F degree oven to accelerate from the recommended drying time of 24 hours at 65F. This produced a layer about 1/16” thick, dry and not sticky, but amazingly anti-resonant.
The combined sound-deadening treatments completely transformed the Njoe Tjoeb’s case. Not only was it much more solid feeling and the transport more muted in operation, but additional sonic clarity was immediately apparent, especially in the lower octaves. The project took about two hours across the course of a day and produced exactly the results I had desired. Highly recommended!
My Super Njoe Tjoeb 4000 is tricked out with the improved power cord, de-coupling feet, tube “ribs”, optional 24/192 upsampler, etc., but its Magnavox case, made of lighter metal than most Band-Aid boxes, seemed a sonic limitation begging to be addressed. Mr. Roberts approached the problem with a thin self-adhesive sheet of asphalt-based automotive sound deadening material stuck on the inside of the upper lid and reported good result. I, of course, had to make more of a mountain out of this particular molehill.
Parts Express (.com) catalogues an assortment of automotive sound dampening products aimed at those who participate in car stereo competitions. I don’t know much about these contests, but competition generally improves the breed, and it’s nice to have someone else pay for the R&D. My $20 bought me a 10”x13” lightweight vinyl sound dampening sheet (#268-030) and a 20oz can of Cascade VB-1S Pro Quiet Damping spray (#268-250).
Originally, I had planned to stick the 10”x13” vinyl sheet up on the inside of the Njoe Tjoeb’s thin metal upper case and then slather it with the sound deadening spray. After a little cranial percolation upon receiving and examining the damping products and their instructions, my plans changed. Instead, I pressed the vinyl sheet to the bottom of the unit between the feet (fits perfectly and can be pressed onto the plastic connectors that extend from the inside of the case) While the lower case upon which the “works” are mounted is of heavier gauge than the top case, it, too, needed some sound and resonance damping.
The inside of the upper case was first cleaned and degreased for best adhesion of the Cascade sound damping spray. This was accomplished using common spray household cleaner followed by window cleaner followed by denatured alcohol. Surface prep always pays off.
It took some time to mask the inside of the upper case to prevent overspray from interfering with refitting the upper case on the lower case. The Cascade VB-1S instructions indicated the product was to be applied warm (70-75F) and kept warm during curing and that no more than 1/32” thickness should be applied per spray coat. Warming the product in a bucket of warm water (as per label recommendations) also produced some impressive spray pressures. I got splatter up to 18” from the work surface. In retrospect, I should have masked at least the outside sides of the case as well. As it was Cascade recommends toluene as a solvent and I substituted Hoppe’s No. 9 to clean up the overspray.
Two coats of the Cascade Pro Quiet were applied with two hours drying time in between coats. Final coat was dried for an hour inside the house and in the sun and then an hour in a 120F degree oven to accelerate from the recommended drying time of 24 hours at 65F. This produced a layer about 1/16” thick, dry and not sticky, but amazingly anti-resonant.
The combined sound-deadening treatments completely transformed the Njoe Tjoeb’s case. Not only was it much more solid feeling and the transport more muted in operation, but additional sonic clarity was immediately apparent, especially in the lower octaves. The project took about two hours across the course of a day and produced exactly the results I had desired. Highly recommended!
