harmonic distortion L15RCY/P seas

[kyselym]

Hi
have somebody measured seas L15?

I would like to know how much of F3 harmonics is there between 1k-2kHz

something like this:
http://www.zaphaudio.com/6.5test/L18-HD.gif

I will be using it in 3way. What crossing point would you suggest? 2.5kHz? 2kHz? tweeters will be seas 27tbfcg.

ps. I'm waiting for drivers now.

[kyselym]

nobody measured L15? nobody can give any suggestion? I just need some direction. I will measured my samples of L15 on my own but this will happen somewhen in the start of summer

[sreten]

http://www.zaphaudio.com/audio-speaker12.html

Hi, not familiar with the L15 you mention, /sreten.

[kyselym]

hi I know of this zaph's design and crossover poits but I hoped that may be zaph will write something like: if I did this again I would set the crossover point lower (higher) for this reason. Or maybe others who worked with L15 would give me some suggestions or what to be careful about but thanks sreten

[Zaph]

Hi kyselym,

If I could do it again, I wouldn't change a thing. 2kHz works very well with that woofer. You could get away with 2.5kHz if you needed, but crossing over at 2Khz actually cuts the 5th harmonic a bit and puts the third harmonic clear off the radar. This is unlike my L18 design which doesn't cut much of the 5th harmonic, and while it's not that high in level, there is a mild tonality change as a result. I am happy with the L18 system as it makes my best choice of compromises, but the L15 design is a little cleaner in the lower treble. In fact, bass depth is similar to the L18 design but only with a much lower output potential.

I have L15 distortion measurements, but they were done before I standardized my testing and therefore don't have much meaning.

The 27TBFCG will swap into the 27TFFC design pretty easily with minor tweaking if you choose to use it. People have used the TDFC with good results also.

The L15 design is ancient, but I leave it up because it does sound good. The Silver Flute system on the other hand I will be taking down someday. Many people have built it and love it, but I feel I could have made better design choices. It will be replaced with something better soon.

Regards,
John

[kyselym]

Hi John,

Thank you very much for reply. 5th harmonic is the reason I asked because I didn't know how much of it will mess up too much. So it seems that 2khz will be fine as 27TBFCG should handle this without problem, am I right? If you would be so kind can you send me the measurements of L15? Till I will be able to measure it on my own, it will be a good start to see where are the rezonances are. I'm not going to compare with other speakres just to make better idea of cone behaviour of L15.

[Dave Bullet]

Hey Kyselym,

What bass driver are you planning to use?

I'm looking at the L15 and 27TBFCG in a 3 way also.... and to increase SAF am leaning towards the L26 (or where you going to do an 8" bass?)

Just curious....

The only concern I have about the L15 is sensitivity matching with a bass driver. The L15 isn't that efficient for mid use... and I don't want to have to pad down the L26 (although I haven't modeled it all yet - just a hunch).

David.

[kyselym]

hi Dave

I'm going to try L26, L22rn4x,2xL22rn4x and L21rnx. Low sensitivity of L15 also concerns me but someone on our local forum has done 3way with L26+L15 so I think there shouldn't be problem...

I will also try active and pasive version. But I still haven't started...no time

[Dave Bullet]

Hi Kyselym,

Did the L26/L15 design on your local forum have any measurements / modeling posted?

If so - I'd appreciate if you could post a link.

Thanks,
DAvid.

[kyselym]

Hi Dave

forum has been erased so there are only backups that are hard to search. But I remebered author of simulations and contacted him. This is simulation for L26/L15
http://pistole.unas.cz/seasy2.jpg
and this is project with L22/L12
http://diyfans.org/vase-petrh2.htm (in czech)
and crossover: http://diyfans.org/vase/petrh2-01.png

but its only simulation and the one with L22 is not measured but I think it will not sound bad(because of pistole's skills and knowledge) but may still need slight tweeks to get it perfect.

Marek