I like to plan well ahead when approaching any project. My current dream is an all tube, all horn system with triamped mains and a sub.
The final speaker system would include a built in horn sub and main channels with 70Hz straight bass horn, mid horn (cone or compr possible), and compression tweeter horn.
My thoughts on amps for the system are as follows.
Sub: PP EL34 (probably pentode mode for max tight bass)
Main Woofer: PP EL34 (Possibly triode mode for favorable dist. spectrum)
Mid: SET or triode strapped pentode for open midrange)
Tweeter: PP ECL82 (high order harmonics rolled of by driver and ears)
My thinking is that the higher order HD of the PP tweeter amp would not be objectionable due to the low levels in this range and the natural roll off of the transformer, speaker and the ear. This would also result in an amp that could be used as a full range amp for use with my current speakers in the initial stages of the project. Given the limitations of my current speakers the ECL82 amp would not need to use a really hurky OPT since a low freq. rolloff at around 40Hz would be perfectly acceptable with the current speakers and absolutly a non-issue once it is put to use in the tweeter circuit. This should save some money on the iron for the first amp. This is also part of the reason for not making the tweeter amp a SE design which requires more expensive iron.
So the first amp to build would be the ECL82 PP. I thought that I might try a transformer phase splitter at the input of the amp (using a smaller CT input transformer rather than the larger traditional phase splitter after the driver stage). The amp would be symmetrical from input to output using two tubes per channel.
So what do you think? Would I be asking for noise trouble putting the phase splitter at the input? Is my selection of topologies sound?
mike
The final speaker system would include a built in horn sub and main channels with 70Hz straight bass horn, mid horn (cone or compr possible), and compression tweeter horn.
My thoughts on amps for the system are as follows.
Sub: PP EL34 (probably pentode mode for max tight bass)
Main Woofer: PP EL34 (Possibly triode mode for favorable dist. spectrum)
Mid: SET or triode strapped pentode for open midrange)
Tweeter: PP ECL82 (high order harmonics rolled of by driver and ears)
My thinking is that the higher order HD of the PP tweeter amp would not be objectionable due to the low levels in this range and the natural roll off of the transformer, speaker and the ear. This would also result in an amp that could be used as a full range amp for use with my current speakers in the initial stages of the project. Given the limitations of my current speakers the ECL82 amp would not need to use a really hurky OPT since a low freq. rolloff at around 40Hz would be perfectly acceptable with the current speakers and absolutly a non-issue once it is put to use in the tweeter circuit. This should save some money on the iron for the first amp. This is also part of the reason for not making the tweeter amp a SE design which requires more expensive iron.
So the first amp to build would be the ECL82 PP. I thought that I might try a transformer phase splitter at the input of the amp (using a smaller CT input transformer rather than the larger traditional phase splitter after the driver stage). The amp would be symmetrical from input to output using two tubes per channel.
So what do you think? Would I be asking for noise trouble putting the phase splitter at the input? Is my selection of topologies sound?
mike