Sparrow-V (the Final Cut)

Sparrow-V

Although the Sparrow-II measures well, I find her too dull for my taste. I like my music to excite me, something that the Sparrow-II has a hard time doing. After listening for a day, it became unbearable.

I wondered whether it’s possible to breathe some life into the SB13PFC25-08. After mulling over it, I decided to give it one more try. This time round, I threw caution into the wind. Instead of going for pretty measurements as in the Sparrow-II, I voiced the speaker by ear.

After re-working the crossover, I hit the jackpot. The music jumps out. The speaker now sings.

I am proud to present the Sparrow-V, the final version in a long line of Sparrows. 

The following measurements were made after I tuned the Sparrow-V. 

Fig 1 – Blue plot=SB13PFC25-08 Low Pass • Red plot=BC25SC08-04 High Pass

This is the new High Pass and Low Pass networks of the Sparrow-V (Fig 1). At first glace, they look the same as the Sparrow-II but the sound is totally difference.

Fig 2 – Sparrow-V Passband

I am relieved that the passband (Fig 2) shows no cancellations. My tuning by ear seems fine so far.

Fig 3 – Sparrow-V Frequency Response

The Sparrow-V frequency response (Fig 3) looks almost the same as the Sparrow-II. Actually, it’s better. The treble depression in the Sparrow-II has largely vanished.

Fig 4 – Sparrow-V Null Response

The Null response (Fig 4) of the Sparrow-V differs from the Sparrow-II. It appears I’ve shifted the crossover down to 2kHz.

Fig 5 – Sparrow-V RAW Frequency Response

The plot in Fig 5 is the RAW response of the Sparrow-V. The Black plot below 500Hz includes reflections in my room. The bass loudness (100Hz to 60Hz) is about 5dB less than the midrange. This plot was made with the Sparrow-V in a Full Space (4 pi)  environment. In a smaller room or near a back wall, the bass will be louder.

Fig 6 – Sparrow-V Impedance

The Impedance of the Sparrow-V (Fig 6) is an improvement over the Sparrow-II. The lowest impedance is at 5Ω whereas it’s 3Ω in the Sparrow-II. The electrical phase is more linear as well.

The other plots like the Step Response, Waterfall, etc look similar to the Sparrow-II so there’s no point in posting them.

Summary

I am glad I decided to take the Sparrow-II one step further. The Sparrow-V is a speaker I can listen to. If you are not convinced, build the Sparrow-V and the Sparrow-II and do a blind AB test.

Everything fell into place in the Sparrow-V. The tempo, the clarity, the intimacy. Same drivers but two different design approach. One following the science, the other, the ear. This is where the art in audio comes in.

Unless otherwise stated, all measurements were made with the mic at 36 ins, tweeter axis. Impulse Window=5ms. No smoothing applied.