Kana & Twl: can you post a link to the threads on Audiocircle that you are referring to ?
El: tubes are VERY much alive in high powered RF and in the music industry. Just ask a "rockin" guitar player. Sure, some of them use SS amps, but a huge portion still cling to and are drawn to the sound of a Marshall, Ampeg, Hi-Watt, Orange, Fender, Mesa-Boogie, etc.. tube head. Even some of the Peavey amps use tubes to great effect to obtain their specific gain characteristics and tonality.
Tubegroover: Low distortion can be achieved two ways. One is to build a very simple yet well designed wide-bandwidth circuit that is relatively stable into the intended type of load that will be used with it. This can be relatively costly as it is harder to keep a simpler circuit stable into various loads and do so while retaining wide-bandwidth. As such, it may require a lot of R&D prior to arriving at a suitable design.
The other method that is FAR more common is to build a pretty decent circuit and then try to correct any deficiencies in linearity with gobs of negative feedback.
The second method is a LOT cheaper than the first to build, design and market. As one might surmise, the cheaper one almost always sounds worse but is more stable over-all, hence the use of such approach by most mass production manufacturers. I think that Halcro tried to combine both approaches but probably used too much negative feedback in order to obtain phenomenally good measurements in specific areas. One could probably add a great deal of "musicality" to the Halcro by changing a few caps, etc.. internally. Just a guess though.
As a side note, I find that i like a lot of Nelson Pass' designed amps. The funny thing here is that they don't have "killer specs" in any specific area*. The distortion is surely not "ultra-low" nor are they phenomenally "fast" in terms of rise time or slew rate. As such, i think that Nelson tried to achieve the best of both worlds i.e. some of the more desirable sonic attributes of tubes with the better measurements and bass impact of SS. From what i can tell by the specs, he seems to have found a compromise between the two. The specs appear to fall somewhere between the two different types of products i.e. lower distortions and faster response than most tube circuits but higher distortions and slower responses than the "best" ( in terms of specs ) SS amps. Has anybody else ever taken note of this or shared these thoughts ? Sean
>
* Other than price : )
El: tubes are VERY much alive in high powered RF and in the music industry. Just ask a "rockin" guitar player. Sure, some of them use SS amps, but a huge portion still cling to and are drawn to the sound of a Marshall, Ampeg, Hi-Watt, Orange, Fender, Mesa-Boogie, etc.. tube head. Even some of the Peavey amps use tubes to great effect to obtain their specific gain characteristics and tonality.
Tubegroover: Low distortion can be achieved two ways. One is to build a very simple yet well designed wide-bandwidth circuit that is relatively stable into the intended type of load that will be used with it. This can be relatively costly as it is harder to keep a simpler circuit stable into various loads and do so while retaining wide-bandwidth. As such, it may require a lot of R&D prior to arriving at a suitable design.
The other method that is FAR more common is to build a pretty decent circuit and then try to correct any deficiencies in linearity with gobs of negative feedback.
The second method is a LOT cheaper than the first to build, design and market. As one might surmise, the cheaper one almost always sounds worse but is more stable over-all, hence the use of such approach by most mass production manufacturers. I think that Halcro tried to combine both approaches but probably used too much negative feedback in order to obtain phenomenally good measurements in specific areas. One could probably add a great deal of "musicality" to the Halcro by changing a few caps, etc.. internally. Just a guess though.
As a side note, I find that i like a lot of Nelson Pass' designed amps. The funny thing here is that they don't have "killer specs" in any specific area*. The distortion is surely not "ultra-low" nor are they phenomenally "fast" in terms of rise time or slew rate. As such, i think that Nelson tried to achieve the best of both worlds i.e. some of the more desirable sonic attributes of tubes with the better measurements and bass impact of SS. From what i can tell by the specs, he seems to have found a compromise between the two. The specs appear to fall somewhere between the two different types of products i.e. lower distortions and faster response than most tube circuits but higher distortions and slower responses than the "best" ( in terms of specs ) SS amps. Has anybody else ever taken note of this or shared these thoughts ? Sean
>
* Other than price : )