Reply with quote #31
Originally Posted by
Kelvin Tyler Bob, In general, the sound of the 300B PP and my take of the 300B DC SE are quite similar. Both give a good sense of presence with the extra power of the PP giving noticeably more dynamism. With my Fostex FE166en single driver speakers the mid-range is pleasantly strong. The higher registers are quite markedly 'beamed', so orientation of the speakers is important and can, indeed, act as an effective 'tone' control. My musical taste precludes excessive, thumping bass, but I do like it to be sharply defined. The 300B PP gives that. I can hardly claim that my modest, space limited, speaker set-up is in any way optimum, but others do comment on the pleasant integration of the music it provides. Personally, I am more than happy with the performance of the 300B PP. I would be very interested to hear the opinions of other folk who have constructed this amplifier. Kelvin What about scratch build, is it possible or really depending on the chassis?
Reply with quote #32
Do we have any further reports on th the 300b pp?
Reply with quote #33
Reply with quote #34
Originally Posted by
Kelvin Tyler I am in complete agreement with many of the sentiments expressed in Sailor's last post. In no way can I claim to be a 'newbie' as I have lived and breathed electronics for most of my professional life. Until about a year ago my only experience with the OTL audio field was within the area of headphone amplifiers. Then, out of curiosity, I picked up a copy of 'Tubes and Circuits' and was immediately intrigued. I decided to build the SOB amp described there and was captivated by the results that it gave with quite modest speakers. My practiced eye recognized sound engineering in this design and this amp still gives me much enjoyment. I have had no stability problems of any kind with this design. No DC offset drift or shorting tubes. At first I was a bit sceptical about the 300B SE. What's this? Four 300B tubes for one watt? Then, as I have previously mentioned, and having some 300B tubes not doing much, I built my DC version of this amp. I then understood what all the fuss was about; outstanding sonics. The performance of this design quickly dismissed all my initial reservations. I have closely studied several of BR's designs with a critical eye and what do I find? Always sound engineering principles, thoughtfully applied, often with great ingenuity and innovation. Apparently simple circuits usually contain subtle features. For me, he has squeezed just about as much performance as is possible out of these designs, consistent with economic constraints. Of course, all engineering involves compromises, but, to my mind, Bruce has made the right calls. At the end of the day, performance and listening pleasure is what counts. Don't get me wrong. I think experimentation is very important and I have been inspired to do much myself, often with pleasing results. It's just that I feel that Bruce has not left much scope for major improvements and we are likely to run into a 'diminishing returns' scenario quite quickly. I am no hero worshiper. I simply try to speak as I find. I don't think you will find any better value than with TS products. No 'snake-oil' and no odour of 'horse manure'. I am sitting here looking at a load of Edcor and Hammond transformers weighing many pounds, and even a stereo 211 design I built a while back with its 1200V power supply and thinking, 'What can I do with these...?'. Great fun this DIY audio! Kelvin