Hey box lovers & MOD freaks!!!
As you may know, I am always chomping at the bit to improve the sound of the small number of grails in my collection. I recently paid a hefty sum for a rare, WX-1 & had the entire slider board swapped out because of a bad Extended bass controller IC. Decent man for you sold it to me without a complete disclosure but overall, a decent unit. If CDn funds weren't so flat against the US dollar, it would have been easier to but you have to strike while the iron is hot or miss out....
The speakers & passives are in great shape & sounds very good. In fact Toshiba did a great job designing the speakers but I want to save the skins & keep them fresh so I decided to go with a dual woofer setup to replace the exisiting drivers & keep them wrapped in plastic to preserve their condition while pumping the jams through some modern cans....
Here's a pic of the proposed setup using some extremely good 6.5" sub-woofers that only require 0.16 cu ft sealed enclosures to reach 50Hz. These will be coupled with 2 4.5" Pioneer Woofers, both 4 OHMS in series to create an 8 OHM load to each amp channel.....
The real problem for this MOD is that the back wave from the larger woofer is interacting with the smaller 4.5" woofer & creating a nasty peak in the upper mid-bass region & muddy bass all over the place except the very bottom octave which sounds OK. This is predictable & no surprise during my initial listening tests. My experiment today is to create a sealed chamber around the 4.5" woofers, using a couple of round plastic food storage containers similar to a margarine tub...This will isolate the smaller woofer from the larger one while converting the 4.5" drivers into midbass/mid woofers & damping their bottom end response, passively, by air-loading.
To briefly explain, if you take a small woofer & create a sealed enclosure around the basket, with a small amount of air inside, it acts to dampen the lower frequencies & increasing impedance in the lower octaves by pneumatic resistance instead of using a crossover to change electrical resistance/inductance...
Pics coming soon.....
As you may know, I am always chomping at the bit to improve the sound of the small number of grails in my collection. I recently paid a hefty sum for a rare, WX-1 & had the entire slider board swapped out because of a bad Extended bass controller IC. Decent man for you sold it to me without a complete disclosure but overall, a decent unit. If CDn funds weren't so flat against the US dollar, it would have been easier to but you have to strike while the iron is hot or miss out....
The speakers & passives are in great shape & sounds very good. In fact Toshiba did a great job designing the speakers but I want to save the skins & keep them fresh so I decided to go with a dual woofer setup to replace the exisiting drivers & keep them wrapped in plastic to preserve their condition while pumping the jams through some modern cans....
Here's a pic of the proposed setup using some extremely good 6.5" sub-woofers that only require 0.16 cu ft sealed enclosures to reach 50Hz. These will be coupled with 2 4.5" Pioneer Woofers, both 4 OHMS in series to create an 8 OHM load to each amp channel.....
The real problem for this MOD is that the back wave from the larger woofer is interacting with the smaller 4.5" woofer & creating a nasty peak in the upper mid-bass region & muddy bass all over the place except the very bottom octave which sounds OK. This is predictable & no surprise during my initial listening tests. My experiment today is to create a sealed chamber around the 4.5" woofers, using a couple of round plastic food storage containers similar to a margarine tub...This will isolate the smaller woofer from the larger one while converting the 4.5" drivers into midbass/mid woofers & damping their bottom end response, passively, by air-loading.
To briefly explain, if you take a small woofer & create a sealed enclosure around the basket, with a small amount of air inside, it acts to dampen the lower frequencies & increasing impedance in the lower octaves by pneumatic resistance instead of using a crossover to change electrical resistance/inductance...
Pics coming soon.....
