Hi
I've recently finished building a tube amplifier (10W pp class A, triode connected 7591's), but don't have any speakers to match its potential. So I thought I would have a go at designing something to suit.
What I had in mind was to modify a 60W Marantz integrated amp I have. I would use the pre-amp section, followed by a 24 dB/oct LR active crossover at ~250Hz, with the mid/high's going to the tube amp driving 2 Fostex FE126's per channel (wired in series, my vintage output transformers only have a choice of 3.75 or 15 ohm taps), and the bass going to the 60W amps in the Marantz, driving a single 10" driver per channel. I haven't decided on the bass driver yet.
I figure the Fostex drivers could be in a ~10L sealed box as bass response is not really an issue. Woofers would probably be in a vented box as I don't have a lot of power to burn in equalizing a sealed box or OB. I'm looking for decent in-room response down to 30-40 Hz. Very high SPL isn't really required, maybe about 105 dB max. My listening room is 4x5 metres.
I've built a few conventional speakers before and know enough to model the bass response, baffle diffraction etc.
Is the concept valid? And are there any similar projects that I could copy from? I'm particularly interested in any equalisation of the FE126's that might be required to smooth their response. I've seen Troels Gravesen's FE126/Fountek ribbon project, but I think I would have trouble in extracting the relevant portions of his crossover.
Any comments or suggestions would be appreciated. I realise the potential pitfalls in designing from scratch but I'm treating this as a learning exercise!
I've recently finished building a tube amplifier (10W pp class A, triode connected 7591's), but don't have any speakers to match its potential. So I thought I would have a go at designing something to suit.
What I had in mind was to modify a 60W Marantz integrated amp I have. I would use the pre-amp section, followed by a 24 dB/oct LR active crossover at ~250Hz, with the mid/high's going to the tube amp driving 2 Fostex FE126's per channel (wired in series, my vintage output transformers only have a choice of 3.75 or 15 ohm taps), and the bass going to the 60W amps in the Marantz, driving a single 10" driver per channel. I haven't decided on the bass driver yet.
I figure the Fostex drivers could be in a ~10L sealed box as bass response is not really an issue. Woofers would probably be in a vented box as I don't have a lot of power to burn in equalizing a sealed box or OB. I'm looking for decent in-room response down to 30-40 Hz. Very high SPL isn't really required, maybe about 105 dB max. My listening room is 4x5 metres.
I've built a few conventional speakers before and know enough to model the bass response, baffle diffraction etc.
Is the concept valid? And are there any similar projects that I could copy from? I'm particularly interested in any equalisation of the FE126's that might be required to smooth their response. I've seen Troels Gravesen's FE126/Fountek ribbon project, but I think I would have trouble in extracting the relevant portions of his crossover.
Any comments or suggestions would be appreciated. I realise the potential pitfalls in designing from scratch but I'm treating this as a learning exercise!