Active cross over - any advantages?

[promitheus]

I also believe you have to use your best amplifier on top.
A question came to mind after reading these posts.
What is important when tailer designing an amplifier for a tweeter?

 

[planet10]

What is important when tailer designing an amplifier for a tweeter?

You can limit the output at the low end -- even design the low frequency cutoff to be part of the active XO. If, like me, you are thinking about a SE tube amp, you don't have to concern yourself with the conundrum usually faced when designing a SET, a big enuff transformer to get deep into the bass means you are compromising the top end of the OPT. By only requiring tweeter frequencies the OPT can be optimized for HF.

dave

 

[jan.didden]

Julian Vereker always said that you wanted to use your highest quality amp on the top... and i tend to agree with him.
[snip]dave

Dave, is that really true? Since most ' quality' of the sound reproduction is determined by the crtical 200-4000 Hz band, shouldn't the mid-band get the best amp?

Jan Didden

 

[planet10]

is that really true? Since most ' quality' of the sound reproduction is determined by the crtical 200-4000 Hz band, shouldn't the mid-band get the best amp?

If you approach it logically it certainly would be... the only situation where i've been able to do an adequate compare was 2 NAIM 160s & a 250 with a set of Linn Isobariks... the system worked best with the 250 on top. Now i'm more into mating the amps with their range (or even more often since i'm usually XOing the T above 10k, just adding a passive single cap in series XO).

dave

 

[CeramicMan]

Unless you tailored the active crossover to match the passive while monitoring the response of the speakers they would sound different. It may be that you son preferred the active because they sounded better for reasons other than the fact that they were active.

The whole point of using active crossovers instead of passive ones is so you can do better things with them. Deliberately mimicking a passive crossover would just be silly.

However, it might provide a valuable insight into the audibility of things like: EM noise picked up by inductors, distortion from hysteresis effects with solid-core inductors, increased driver Qes (and Qts) due to the inductances and resistances, IM distortion and cross-talk due to mutual inductance... Increased volume settings to counteract passive attenuation....

CM

 

[Bill Fitzpatrick]

Unless you tailored the active crossover to match the passive while monitoring the response of the speakers they would sound different. It may be that you son preferred the active because they sounded better for reasons other than the fact that they were active.

The whole point of using active crossovers instead of passive ones is so you can do better things with them. Deliberately mimicking a passive crossover would just be silly.

CM

I agree but unless you deliberately mimic the passive you are listening to something more than active vs passive. No doubts the active offers additional possibilities for tailoring the response, narrow notches for example. My original comment at the beginning of this thread about active crossovers being of marginal value was made in reference to the mid/tweet crossover point. Your, and others, arguments in favor of active bear more toward the woof/mid area.