decided to mate the M5a with Vifa's elderly 1"
aluminum dome tweeter, the D25AG35-06. Though outdated,
it still commands a large following due to its bewitching
highs. The D25AG35 is demanding. An LCR (Series Notch
Filter) must be used to further damped the tweeter's
resonance. Neglect that and it will irritate, especially
when crossed low.
a more forward vocal projection, I crossed the D25AG35
at 2,500Hz with a slope of 18dB/octave. The Violet
Plot on the right is the unsmoothed, Gated Summed
Response of the tweeter with the M5a. I'm not overly
concerned with the peak at 4,000Hz. Even with a gated
measurement, I believe the cause of uneveness in the
tweeter's response is from room reflections.
final plots are the Frequency Response and Impedance
of the Robin. The all important critical midrange
region is smooth. No peaks. No valleys. Overall impedance
is friendly. Generally 8 ohms from bass to the mids,
dropping down to 4 ohms at 3,000Hz. Nothing that any
competent amplifier cannot handle.
all that's said and done, how does it sound? First
off the blocks was Strauss. Violins are not strained.
Cymbals don't sound like glass shattering. Just the
right amount of Oomph in the lows. Promising, so far.
was next. "Loved by You" in her latest album
"Perfectly Clear", is particularly demanding
on the crossover. This track is far better than a
warble tone generator. Jewel's heart wrenching rendition
came through without any edginess.
a brighter note, Mindi Abair followed. This girl is
outstanding. She can hold her own with the best in
the business. Her sax is precise and commanding. Lastly,
Armik's guitar came on for transients. The attack
in the strings was fast and crisp. The mellowness
one expects from an acoustic guitar was faithfully
reproduced. Most important of all was the upper bass
ability to keep pace with the speed of his guitar.
This is where the "Symmetric Motor Drive"
technology shines. Its in the articulation in the
summary, I'm exceeding pleased with the Robin. For
this level of quality, a pair of bookshelf would easily
cost more than $1,000 retail.
> Robin | Robin-II | Robin-IIa
Bass Reflex Bookshelf
D25AG35-06 1" Aluminum Dome Tweeter
M5a 5" Metal Cone Midwoofer
Low Pass (12dB/oct)
High Pass (18dB/oct)
(1 watt / 1 meter)
Internal Dimensions (WHD)
7" x 12-1/2" x 9"