Vandy sub owners-crossovers for 2WQ


Given a amplifier with 50k input impedence and Vandersteen's recommendation that the filter be set at the next lowest value ( according to the WX-2 box )which is 33K, my question is: If the amplifier is an actual 50K input (as is the case with FET transistors used in the input circuitry)why would you want to set it below the 50K? The instructions say set it for the input impedence---very confusing)If you want a 80hz high pass wouldn't anything but a 50K alter this? Also, does anyone have the formula for computing capacitor value for various input impedences to achieve a 6db high pass @ 80hz? Thanks
bigtee

Showing 2 responses by maxgain

Bigtee. This very issue has caused me alot of anguish. AVISO! CAUTION! WARNING! DO NOT CONTACT RICHARD ABOUT THIS!! Scott is only trying to be helpful with the suggestion of calling Richard but I have done the very thing he is suggesting and I regret it! Richard came unglued!
My dealer told me that I should experiment until I found the setting on the box I liked best once the woofer was fully broken in. I setteled on the 100k setting finding it to sound best to my ear in my system(which happened to be the input value of my amp). I then went back to the dealer to order the x-2 fixed filters and told him this information. The dealer then said "The procedure is to order the next value down.", in this case the 75K X-2 fixed filters. ($125 a pair I might add)I went along with this since I figured, he is the dealer and must know something about this that I don't. I got the 75k x-2 filters and they did sound better than the "box"(WX-2), but I beleive it had more to do with eliminating the sound of the WX-2 and the colorations of the second set of cables. I started to question the "next value down" thing after another dealer had made it quite clear to a friend of mine that had a very similar(same brand of amp with the same input value) system that the way to go is with the 100k X-2. I have had several other dealers tell me since that it "usually" works best with the filters or the setting on the box that match the input of the amp. My dealer later told me when I asked him about the logic of buying the next value down as he had suggested, that he had never said that to me, and that I was one of those guys that always worries about his system(he already has my $$$$$). My dealer doesn't know his ass from his elbow! I just bought a set of 100k X-2's (used) and they sound great in my system! The 75k's are for sale here on Agon if anyone needs a pair. The whole point is that "one setting below" is ONLY a starting point. Use the setting or the fixed filter value that sounds best in YOUR system.
Richard can't understand that many people are confused by the way the manual is written, including his own dealers. I told him a friend of mine also had some confusion about it and he suggested that my friend was a "moron". Well Bigtee you and I are both "morons". DON'T CALL RICHARD! It seems that phone calls anoy him, but it seems to me he would figure out that there needs to be some imrovement or clarification in the way the procedure is explained, and then he may not have to talk to us "morons"!
Don't worry about what the sensitivity setting on the back of the woofer reads. Sounds like you have it about right with the impedence matching and the woofer level adjusted to suite your room.
After you get it dialed in get the fixed X-2 filters in the value you liked best to get rid of the WX-2 like I have or buy some model 5 filters like Sdcampbell uses.
You might try listening to a test disc like the one Stereophile produced with bass warble tones just to give you a reference point for level.Pop and Rock Recordings vary wildly these days as to the amount of bass, so use the best acoustic bass recording you have for the final level and setting evaluation. I like a Bobo Stenson Trio disc, titled "War Orphans" on ECM, track 2. You will still find recordings that sound "heavy" after you are done, I think it is the recordings and probably not your rig.
I'm going to try an ASC bass accelerator sub stand for mine, which should give me even more clarity and punch in the lows. ASC Tube traps would be next but I don't have it in the budget. Make sure that you have good isolation under all your electronics ecpecially the source components. Vibrapods are a good start or a Bright Star Air Mass or Big Rock would be even better. It will clean up everything and give you real athority in the bass. Two 2Wq's are going to move air like crazy and make real isolation critical especially if you run tube amps and pre amps.