I did not make my mind about it but I have some “concerns”. Using SS amps and hearing different SS amps I do not like their bass and the notion of a powerful enough DSET to be able to drive ULF in A1 was born. Sounds logical. However, recently I employed a vacuum tube crossover before my SS amp and it looks like addressed all my frustrations in SS sound. Listening the very same SS amp with bass colored by tube crossover I do not experience the typical sense of overly “pressed” bass and hard “room clipping”, quiche in opposite, the room sound very soft with bass being almost like a butterfly sits on your shoulder – very different from the sound of the same SS amp.
I certainly do not propose this as a universal solution for better bass but since I did get in my estimation a better bass then I would like to think what have I’ve done.
I did not test my tube crossover but I am sure if did then I would find it quite distorted. A sequence of 4 cathode followers with 12AX7 – it got to be brutal. If I use the same crossover as a line-level buffer (with no filters) then I am sure that I would not find it transparent enough. Furthermore I would be most likely bitching about bass. However, in case of multiamping and use the crossover only as low pass filter for ULF it look like the distortions that the crossovers create become virtues.
So, I wonder, is it anything in my finding about this way to use ULF worth to be capitalize in more global scale or it is just my erroneous perception have found a satisfaction in my private case? I do not have answer to it. But what I would like to do is to propose to someone who use powerful SS amps to drive bass and who have own dissatisfaction with some aspect of its quality to try to color that bass with passing it across a “weak tube” buffer. It is possible that harmonic distortions that small signal tubes do have very positive impact to whatever they impact.
I know that it sounds like foolishness but I do have two identical SS amps with two identical filters and after much contemplation decided to abandon the elegant and very clean amp with passive line filter and to employ very non-graceful solution with 4 active tubes staged before my SS amps. If somebody would do it I would very much criticize this approach. However, in my defense I do have my well recognized reasons. What I am doing not is sharing my reasons with you and proposing to confirm it with “second opinion”.
I do not feel that my employment of active filter is right thing to do system design-wise; even it gives subjectively better sound, closer to where I would like it to be. I would like to know if it possible to make it “properly”. The proper implementation in mind would be the use of powerful SS amp to drive ULF that will have the distortion pattern (or whatever is responsible for sonic subjective improvement while I use tube crossover) similar to what my current tube crossover + SS amp gives. My task is very limited – I do not need a full range SS amp. What I might be OK with is DSS a dedicated to bass only SS PP amp. It is highly possible that all that SS amps need to drive infra-bass is to have a few harmonic shaping stages in a signal pass. I did not know if anybody look into this but I do not mind if somebody do and let me know about the findings.
Romy the Cat
"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche