Hi Juan, welcome.
You will get very many different recommendations to your post, so I will focus on answering your questions instead.I have listened to, and auditioned, the SCM 150, modified Klipschorns, and scores of JBLs including their big 3way (9900?), so I can offer anecdotal information.
1) & 6) Subjectively speaking the ATC sound is neutral, with very dynamic peaks, very "fast" sound, and very controlled and not overabundant bass & upper-bass frequencies. It is not harsh ("analytical") and it is detailed. They also can play loud enough to simulate real life conditions. Finally, they do not have a romantic, warm, etc, sound. They are fast and furious; subjectively speaking I don't find them fatiguing, I find them exciting and precise.
If I had a large space, which I do not, the 150 would be on my short-list. But then, so would the big Magico, the big Gamut, the big Vivid Audio...
2) My experience is that most ATC models are slightly bash-shy compared to the competition: it is not prominent and it does not go very low. OTOH, the bass you get is very clear & controlled. The 150 is a notable exception: it *DOES* produce bass and in high amplitudes!
Overall, the 150s are outstanding speakers which can fool you into thinking you are actually listening to a full Mahlerian orchestra live (or Led Zep live, etc)
3) Years ago I had the actives & later the passives for a short while at home.
Passive: I powered these with a 250W / channel Class A amplififier (i.e. a 1.2kW device). The result was good, I could drive them adequately, but more power would always be useful.
Given this, and if I did not already have power amps, Active would be my choice for practicality & price (top-quality amps capable of driving the 150 well are priced out of this world). The amps included in the active one were very decent and performed excellently.
4) You need a pre that is hyper detailed and, if possible, wide bandwidth: subjectively, such pres sound "fast" and the 150 are "fast" speakers (ie.e their drive units powerful magnets).
So, definitely solid-state unless you can afford a CAT SL1 extreme (tubes) or similar.
5) Spectral is an excellent choice, some of their older models are good and affordable. If you go passive: pre+amp from the likes of Spectral, or Soulution, etc do the job; for a very slightly "warmer" sound, Symphonic Line, BFA, MBL.. etc.... I am only mentioning the ones I'm familiar with, there are many others.
7) Definitely ATC for home use
8) I haven't listened to the Kendrick versions. They are, however, a totally different design, with wide dispersion characteristics, especially in the mids-highs.
9) I have listened to Klipschorns extensively in the past. Compared to the 150 they will sound thin but much more generous in the bass. They produce a huge sound, just like the 150, and they do not need huge amplification -- but they will NOT play well with "3 golden watts".Based on my experience, the Klipschorns, when set-up correctly and modded, are superior for home use to most JBLs (except for the 9900?, or the model below -- even there I'm not sure). Mind you, JBL is not Harman's brand primarily destined to home use; Revel is.
Anyway, a long post, hopefully useful to you. Good luck!
You will get very many different recommendations to your post, so I will focus on answering your questions instead.I have listened to, and auditioned, the SCM 150, modified Klipschorns, and scores of JBLs including their big 3way (9900?), so I can offer anecdotal information.
1) & 6) Subjectively speaking the ATC sound is neutral, with very dynamic peaks, very "fast" sound, and very controlled and not overabundant bass & upper-bass frequencies. It is not harsh ("analytical") and it is detailed. They also can play loud enough to simulate real life conditions. Finally, they do not have a romantic, warm, etc, sound. They are fast and furious; subjectively speaking I don't find them fatiguing, I find them exciting and precise.
If I had a large space, which I do not, the 150 would be on my short-list. But then, so would the big Magico, the big Gamut, the big Vivid Audio...
2) My experience is that most ATC models are slightly bash-shy compared to the competition: it is not prominent and it does not go very low. OTOH, the bass you get is very clear & controlled. The 150 is a notable exception: it *DOES* produce bass and in high amplitudes!
Overall, the 150s are outstanding speakers which can fool you into thinking you are actually listening to a full Mahlerian orchestra live (or Led Zep live, etc)
3) Years ago I had the actives & later the passives for a short while at home.
Passive: I powered these with a 250W / channel Class A amplififier (i.e. a 1.2kW device). The result was good, I could drive them adequately, but more power would always be useful.
Given this, and if I did not already have power amps, Active would be my choice for practicality & price (top-quality amps capable of driving the 150 well are priced out of this world). The amps included in the active one were very decent and performed excellently.
4) You need a pre that is hyper detailed and, if possible, wide bandwidth: subjectively, such pres sound "fast" and the 150 are "fast" speakers (ie.e their drive units powerful magnets).
So, definitely solid-state unless you can afford a CAT SL1 extreme (tubes) or similar.
5) Spectral is an excellent choice, some of their older models are good and affordable. If you go passive: pre+amp from the likes of Spectral, or Soulution, etc do the job; for a very slightly "warmer" sound, Symphonic Line, BFA, MBL.. etc.... I am only mentioning the ones I'm familiar with, there are many others.
7) Definitely ATC for home use
8) I haven't listened to the Kendrick versions. They are, however, a totally different design, with wide dispersion characteristics, especially in the mids-highs.
9) I have listened to Klipschorns extensively in the past. Compared to the 150 they will sound thin but much more generous in the bass. They produce a huge sound, just like the 150, and they do not need huge amplification -- but they will NOT play well with "3 golden watts".Based on my experience, the Klipschorns, when set-up correctly and modded, are superior for home use to most JBLs (except for the 9900?, or the model below -- even there I'm not sure). Mind you, JBL is not Harman's brand primarily destined to home use; Revel is.
Anyway, a long post, hopefully useful to you. Good luck!