VIB 170 BP

Characteristics and sound properties

When developing the VIB 170 BP, the main objective was to create a fairly compact column speaker with an extremely deep bass output, which is capable of reproducing the deepest regions of the audible frequencyspectrum. A common bassreflex housing can reach this aim only partly. Therefore, a very rare type of cabinet has been realized, at least when looking at fullrange-loudspeakers: A double-sided ventilated bandpass. In this layout, a woofer which is mounted on an inner separation wall, is operating on two bassreflex-tuned volumes, a larger one and a smaller one. By means of a subtle tuning of the two cavities, a linear frequency response down to 35 Hz (-3 dB) could be obtained with a housing of only 75 liters. Not until then, the sound pressure level starts to drop rather quickly. The lower cut-off frequency (-10 dB) is located around 24 Hz. Some very large bassreflex speakers are capable of reaching similar cut-off frequencies, but the SPL already starts dropping at much higher frequencies. This is why those kinds of loudspeakers sound less voluminous and deep.
Due to the exceptionally high excursion limit of the TIW 200 XS - 8 Ohm, the maximum obtainable sound pressure level is already physically tangible and more than sufficient even for large listening rooms.

Another design feature of the VIB 170 BP is the wide frequency range of the AL 170 - 8 Ohm. By means of a sophisticated crossover set-up, we have been successful in taking advantage of the outstanding acoustical properties of the AL 170 - 8 Ohm from 100 Hz up to 8 kHz. Not until then, the established ceramic tweeter KE 25 SC - 8 Ohm takes over to render the uppermost 1-2 octaves. By this layout, the widest part of the audible spectrum is reproduced by only one driver, which helps acoustical imaging and leads to a strikingly precise stage arrangement.

So how does such a fancy build sound like? Like the best of both worlds: The spatial precision and dynamic of a good fullrange driver, paired with the brute bass power of the TIW 200 XS - 8 Ohm in the bandpass cabinetand the silky, delicate treble of the excellent ceramic calotte.
At the same time, the whole loudspeaker plays all of a piece and acts absolutely neutral in terms of tonality. Moreover, not a hint of the often-cited "sponginess" of the bandpass principle could be observed, far from it: the low tones sound firm and massive, fully grown, thus becoming to many a much larger boxes.

All around, the VIB 170 BP can be said to be a felicitous loudspeaker, which combines the advantages of a high class fullrange speaker, a multiple way box and a strong subwoofer in one slim cabinet.

TIP: The low frequency part of the VIB 170 BP, without the tweeter and the midwoofer, and without the crossover network, makes a superb subwoofer to complement even large home cinema systems, single- or pairwise.

Component parts list for 1 box

Tweeter
1 pc.
Midwoofer
AL 170- 8 Ohm
1 pc.
Woofer
1 pc.
Crossover
1 pc.
Terminal
1 pc.
Damping material
Lamb's wool
0,5 bags
Special wood screws
5 x 30 mm
15 pcs.
Special wood screws
4 x 25 mm
8 pcs.
Countersunk head screws
3,5 x 25 mm
4 pcs.
Cable
2 x 1,5 mm²
3 m

Technical Data

Rated power
120 W
Maximum power
200 W
Nominal impedance Z
4 Ohm
Übertragungsbereich (-10 dB)
25–25000 Hz
Mittlerer Schalldruckpegel
85 dB (2,83 V/1 m)
Trennfrequenz
100 Hz/7500 Hz
Gehäuseprinzip
doppelt ventilierter Bandpass / double sided ventilated bandpass
Net volume
75 l + 3,5 l
Außenmaß Höhe
1108 mm
Außenmaß Breite
238mm
Außenmaß Tiefe
408mm

Frequency- and impedance response

Press

Extract from Klang & Ton

“We would never have anticipated the quality of sound that we heard – amazingly three-dimensional mid-range sound, both tangible and direct, as one expects from very good full-rangespeakers. The tweeter was even more transparent than we have seen it perform in the past, thanks to the high separating frequency. And what part does material resonance play? This range certainly does not soundunpleasant or intrusive, probably because it fades away so quickly and is within a very narrow bandwidth. Vocal “s” sounds come across completely naturally and at a reasonable volume, but what you notice is that they are very energy-charged without being at all intrusive. This sound is, after all, being radiated by a large cone area rather than being generated by a comparatively tiny diaphragm. Dynamic attacks on guitar strings explode with sound while cymbals acquire real substance. This whole tapestry is founded on a carefully balanced lower frequency range and fantastically deep, taught bass. Up to now, we have never had the pleasure of hearing that from a bandpass cabinet. The drivers complement each other perfectly and the transitions are absolutely seamless. As we have often noticed with other systems based on full-range speakers, the three-dimensional soundstage is very accurate and clearly defined; the low-bass and broad-range treatment allow the listener to concentrate on the musicians. The icing on the cake is the highly surprising level accuracy: when a very large, powerful church organ floods the listening room with deep bass, it is enough to put one in awe. Okay, this does require a fair amount of amplifier power – with a 60 watt symasym amplifier, this Visaton speaker sounds great, but if you want to make it really shine, go for a good 200 watts and more.

Conclusion

The introductory initials of the VIB 170 BP could stand for “very interesting box”, which puts it in very good company if one looks back over its family tree: this VIB really deserves to be bear the title “very interesting”."