If you add a supertweeter, it should have a lowpassfilter on the FR, otherwise you have two speakers in the same passband with phase issues and so as result. So i surely would add an inductor on the FR to make that filter (if not more parts).
Adding a super tweeter to FR, I see three ways to do this
1/ Just treat FR strictly as a midbass and add
tweeter somewhere around 3.5/4khz
2/ cross higher up, make more use of FR but with possible C2C issues
3/ have FR crossoverless and live with beaming, the supertweet having little contribution and only above 10khz possibly in an Omni arrangement
1/ Just treat FR strictly as a midbass and add
tweeter somewhere around 3.5/4khz
2/ cross higher up, make more use of FR but with possible C2C issues
3/ have FR crossoverless and live with beaming, the supertweet having little contribution and only above 10khz possibly in an Omni arrangement
How most people i know do it is use the supertweeter at about 7 to 12kHz with a single cap as filter for the tweeter and an inductor on the FR (so a 1st order filter). But mostly on fullrange drivers that don't go up a lot (Lowter DX4 that cut of at 13Khz as example). C2C is not fully right, that is true, but if the tweeter mebrane and the FR membrane are aligned (the sound is still very coherent and no obvious phase issues are heared, even if the tweeter (like the fostex supertweeters that are used a lot for this) is laying on top of the cabinet.
Here is my experience with supertweeter vs. fullrange:
My fullranges are Alpair 7.3; Seas 6.5" & Seas 8". They are DSP controlled through a MiniDSP 2x4HD. I have several amplifiers so I can switch quickly, and I compared directly against my Spendor SP1/2R2, which have a supertweeter. And I find that:
All my FRs have more natural and better treble quality than the Spendor´s supertweeter.
FRs need a Fast/WAW to maintain high quality treble at louder listening levels
The passive filter in the Spendor create unfortunate phase rotation. In addition, we loose the "point source" concept at the worst possible high frequencies. In sum, this create unfortunate timing issues. It is quite easy to spot this through REW measurements.
My fullranges are Alpair 7.3; Seas 6.5" & Seas 8". They are DSP controlled through a MiniDSP 2x4HD. I have several amplifiers so I can switch quickly, and I compared directly against my Spendor SP1/2R2, which have a supertweeter. And I find that:
All my FRs have more natural and better treble quality than the Spendor´s supertweeter.
FRs need a Fast/WAW to maintain high quality treble at louder listening levels
The passive filter in the Spendor create unfortunate phase rotation. In addition, we loose the "point source" concept at the worst possible high frequencies. In sum, this create unfortunate timing issues. It is quite easy to spot this through REW measurements.
Hello, I tried this approach with a Jordan JX92S full range supplemented by a xt19 tweeter (not exactly a super tweeter, but the idea was to get more sparkle).
After a lot of experimentation and several months of listening, I ended up going for a classic 2 way crossover. The issue with the “parallel” approach was getting the phase aligned over a wide frequency overlap.
After a lot of experimentation and several months of listening, I ended up going for a classic 2 way crossover. The issue with the “parallel” approach was getting the phase aligned over a wide frequency overlap.
If one employs a 1st order Series XO between the FR and the super tweet at any frequency of choice most, if not all phase issues will be go and the system will be seamless, very coherent and very musical.
Worth trying, very easy to implement, but remember No Zobels or any other correction circuits. They'll destroy the magic.
Worth trying, very easy to implement, but remember No Zobels or any other correction circuits. They'll destroy the magic.
Change in frequency response off-axis. Even with a series crossover, the issue is not resolved because it can’t help with acoustic phase differences.
If the full-range has a well-controlled acoustic response in the overlap, it might be ok. The Jordan suffers resonant peaks, which no doubt cause rapid phase change. Other drivers may be better behaved. But I suspect it is a common problem.
If the full-range has a well-controlled acoustic response in the overlap, it might be ok. The Jordan suffers resonant peaks, which no doubt cause rapid phase change. Other drivers may be better behaved. But I suspect it is a common problem.