Updated: 06-Sep-01 14:12
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#5


Building Tube amps without the right T&M Equipment becomes a dead end...

Yesterday evening, I finalized a facelift for the MU-stage of the GOLIDAV KR300BXLS amplifier. Well, who cares? Don't we facelift and tweak all the time in and around our amplifiers?? So what is so special, it must be mentioned in my column?? The point is, that in our beloved audio hobby a lot of people are tweaking and tossing and turning around like unguided missiles.... yes we do and I think this is becoming the problem. The goal has become the road. There are more possible tweaks, a man can do in his whole lifetime.  Seriously, I see so many VOODOO kind of sound improvements, that I some times get frustrated. I dear to bet, that all those people, putting silicon on top of electrolytes for damping, listening to the direction of interlinks, building batteries in the shield of the cable, using golden power cords, putting wooden caps on the tubes, interlinking their amps with cinch cables of 20.000 DM, making knots in the speaker cable (really true!), putting Riken Ohm resistors in series with the signal LED (ok, that is a joke) and so on and so on, that those people have not optimized their basic amplifier yet............ It is like washing your car for improved aerodynamic behavior, ignoring the fact that one of the four cylinders is not working.  So, done, I have said it, it is of my chest now, so let the reactions come all over me ! Prove me to be absolutely wrong !

Where was I? Oh yes, the GOLIDAV amp facelift. In the Tube Portal, you can read the whole article with, as usual, technical backgrounds. Basically the moral of the whole story is, that without the proper T&M equipment (in this case a FFT analyzer), I would never had the insight to change the design on a critical point. Now, my amp gives more output power, sound more relaxed/spatial and sound less colored when driven at maximum levels. The amplifier sounds BIGGER than it actually is. In the "old" days, I would have been completely satisfied with the amp and started listening to the influence of the color of the chassis; after all,  the signals looked good at the oscilloscope. By the way, how many DIY's do you know who have a function generator and oscilloscope ??? Every one should have these two pieces of equipment, unless you only want to built 1:1 from other people designs. That's fine, is certainly not unworthy or something, can also lead to good results, but than you will never have the opportunity to develop the design further and you are also doomed to not get the best results of it. After all, not every one is updating and publishing his designs, after a facelift or tweak has been done......... So you will never know what the latest status is. Unless you look for yourself.....  on the scoop !!

For those without scopes and stuff, I uploaded the revised design (revision 3) in the download area, so don't worry........

 

Happy Listening and Building !!!!

Doede Douma

 


IMPORTANT: The information provided on this page is intended as guide for DIY activities and therefore free to copy and or publish. If any one wishes to use any of the information from my WEB site, please make sure to refer and footnote to my URL Link as source! Doede Douma