Rerurn to Romy the Cat's Site


In the Forum: Melquiades Amplifier
In the Thread: Planning my DSET
Post Subject: Very commendable and noble jobPosted by Romy the Cat on: 3/2/2019
 anthony wrote:
Briefly, I tried altering some operating current on the valves and now have a better understanding of how DSET can be used to shape the sound.  It is one thing reading about it but another thing entirely when you turn a knob on the amp and a particular portion of the sound changes...such a powerful tool.
I am not sure I agree with it. I do not see in Milq a great ability to altering some operating points. The driver stage is set, you can drive 25% more or less current of voltage but I do not feel that it changes sound very drastically. The same is with output stage. It does change very slightly the damping of the output stage. Well, I need to admit that the ScanSpeak array are very sensitive to dumpling, I have written about it before. A normal speaker is not so sensitive to damping so much. What I disagree is that altering operation point is a way use DSET. If you say “charge of the OTP sections for each channel then I would say YES, this is how you charge the damping. Not the changing of operation points. The objective of operation point is to set the tube foe symmetrical clipping, nothing else\. It means that for a max power of operation against the very specific load the top at the bottom sinusoid much clip at the same time. The top is current and the bottom is voltage (or wise versa, I do not remember now), you need to make sure that when they clip it will be symmetrical. DSET should clip by transformer, not by driver tube. From all that was said it is understandable that there is not a lot of operation point flexibility in a well designed amp.
 anthony wrote:
Still Macondo is incomplete and there are sound issues around the bass and upperbass, but mids and highs are delightful.  I have performed some initial measurements towards room treatment for bass and the left Bass Cannon in its current position is flat to 18Hz in room, which is excellent, but I do have some work to do to get flatter in-room frequency response below about 150Hz, with some room modes from about 40Hz.  Some impromptu trapping made a good start towards this goal, so hopefully over coming months I will eventually have a suitable solution.

Flat to 18Hz is a bit too god to be true. Not that I do not feel that it will not go down to 18Hz, this is well expected, but to be flat from 100 to 18… I would not believe in such a luck. I do not say imposable as I have seen it. Do not waste you time on trapping and the reset of it. Finish you upperbass, connect the things and I will let you know what sweep you need to post to calibrate the things properly. Do not fight with you room. This is bridge to nowhere. You your room imperfection if you have them as you expressive tools and factor the imperfections into the Macnondo sound. As you done with upperbass I will teach you how to do it. Without the upperbass there is no need to listen the Macondo. With the rest you have doe a very commendable and noble job.

Rgs,
Romy the Cat

Rerurn to Romy the Cat's Site