Vandersteen 4

The statement about doubling the noise floor with eagle 400s in my previous update is completely wrong. It will lower the noise floor by about 8 db according to specs:
http://www.eagle-audio.com/specs.htm

Now, I'd like to try some 400s. Recapped my current Eagle 2a with blackgates and put in IXYS hexfred diode bridge. Also squeezed in 280,000 uF of capacitance. All of these helped the sound/noise floor of the system a lot. Bridged 400s would be very interesting. Also recapped WX4, but limited blackgate, but did put in Schokty type diodes which was major change. Also upgraded ICs in WX4.

Meles---Did you do the work on your Eagle 2a yourself? I have a 2b, and have been thinking about having it upgraded.

neat to see somebody pushing to keep this speaker on an improvement path. Richard answers the phone.
I had 3 a sig but in a smaller room. Big SS mac poweramp had viselike grip on low end.
have you tried soundanchors on your 4's ?
probably need to modify the 3 a model or have custom made. ????
jim

Following this now. bdp24. Yes. I did the work myself. A definite no no for those not familiar with a soldering iron. I only use mine as a sub. If that is the case for you, then don't upgrade.

The one project that is not terrible on this amp would be upgrading the bridge rectifier as it is mounted on the chassis between big caps and transformer. The IXYS was very nice and $25 or so. A user could also replace the large capacitors too, but their is no guaranteed sonic upgrade, but these computer grade caps are becoming scarce so snap some up. The vintage blackgates that would work are crazy, crazy money and custom install and less capacitance. Not worth it. 

tomic601, 3A sig is very good, but 4 ohm speaker. I like tubes a lot so never seriously looked at them when upgrading from 2ce. The Vandersteen 4a comes with 4 spikes in the best. A MAJOR tweek for the 4a is to remove the back two spikes and put one small cone in the back. With the two front spikes you can still level, etc but the cone provides much more stable mating to floor. The 4a is twice as deep as a 3. Not aware of Sound anchors.

Upon consultation with experts, well in fact bridged amps do make the noise floor worse as originally stated. So STRONGLY do not recommend Eagle 400s for Vandy 4a. The improvement with diodes, ICs, and blackgates were substantially audible and improved the overall sound floor quite remarkably. Schottky diodes in the crossover made the system sound almost like it was driven only with tube amps (currently use 300b and 6b4g push pull amps for triamping 4a). Bridged amps would be a step in the wrong direction since they would worsten the noise floor. With any of these sub powered systems with active crossovers, sound floor/noise floor is weakened due to additional amplification stages and crossover electronics. Despite claims that noise floor (sound floor) is less important in the bass, these upgrades have shown me that it does matter greatly.