John Krutke escribió:Vifa DQ25SC16 additional test results...
Frequency response, 0,15,30 degrees horizontal off axis
Frequency response, 0,15,30 degrees vertical off axis
Harmonic distortion (new November 2009 test)
Harmonic distortion +10dB
First up, I wanted to see if it matters which way the oblong phase shield on the DQ25 is oriented. Nope, doesn't matter, barely any difference if it's mounted horizontal or vertical. Next up, I wanted to show folks how it behaves at higher levels, particularly in comparison to the small dimple dome above. The DQ25 is one of the best neo domes out there in anywhere near 4 times it's price range. While it has no rear chamber, the voice coil former ventilates the small volume under the surround to the larger volume under the dome. This keeps it clean and allows a bit higher output for a non-chambered tweeter. The +10 dB HD sweep still looks excellent. However, I'd like you to note how and where the tall odd order harmonics increase at higher levels, particularly the F5. Then compare this to the same thing for the SB Acoustics SB29RDCN shown above. This pretty much explains why I cross over higher in the multi-driver ZA5 designs that are expected to play louder. When doing system design, you have to think about how a driver's design limitations are going to affect things.
While the DQ25 is excellent, the SB Acoustics SB29RDCN will play cleaner lower in frequency at higher levels. Don't count on me redesigning the ZA5 to use the small dimple dome however. I work around the DQ25's limitations and thoroughly enjoy the pricing.
"Be conservative in what you do, be liberal in what you accept from others" (RFC 793) Jon Postel
Si queréis echaros unas risas, en esta publicación pitufa online se marcaron unos ABX a ciegas de cables eléctricos y por supuesto no encontraron diferencias; traduzco un párrafo:
"Usando el protocolo de prueba ABX a ciegas, no pudimos encontrar diferencias entre un repertorio de cables eléctricos genéricos y el Nordost Valhalla. Luego no podemos concluir que distintos cables elétricos suenen distinto durante una prueba ABX a ciegas. Pero tampoco podemos concluir que no hay diferencias. Simplemente no pudimos probar que las diferencias se puden detectar de forma estatisticamente significante mediante un protocolo ABX a ciegas."
