In-Room Response

While a Gated Frequency Response Sweep is imperative in tuning speakers, it does not take into account room reflections.

For a more realistic perspective of how speakers interact in a room, a Real Time Analyzer Sweep with Pink Noise is a far better option.

Figure 41 is the RTA plot of one of the speaker in my listening room. Room is deliberately left untreated to simulate a normal room.

Resolution of plot is 100 Bands from 20Hz to 20,000Hz. This is a much finer resolution than a conventional 31-Band display.

(Figure 41) 100 Bands RTA Sweep - 1 Meter, 2.83V
Overall, I must admit I am more than satisfied with the results. Sensitivity is about 81dB. Frequency Response is 20Hz-20,000Hz and more importantly, at +/-1dB in the critical regions. With this level of precision, the speaker is very close to that of a Reference Monitor.

The Moment of Truth

Time for some music. Speakers are 3 Feet away from the rear and side walls, 6 Feet apart, toed in. Listening distance is 8 Feet. No subwoofer, no EQ.

First off the blocks is Vivaldi's Four Seasons, followed by Mozart, Chopin and Strauss. For such a small speaker, I did not expect it to be delicate and yet forceful. When the passages were soft, the speakers were emotive. When it went loud, there was authority. For something more taxing, I had Hilary Hahn playing Bach. The violins passed with flying colors. Now I can sit back and enjoy Heifetz.

For female vocals, Nana Mouskouri had the honors. "Only Love" is capable of revealing peakiness in the mids. I was relieved that the speakers managed this track. Next in line is one of my favorites, Amanda McBroom's "Fool for Love" from her Midnight Matinee album. Her voice not only cuts right through the mix but had just the right amount of presence. Sarah Brightman's duet with Cliff Richard in "Only You" was comforting. It's inspirational to see Cliff Richard still has it. And there's "Don't Cry For Me Argentina". Almost brought tears.

On to Andrea Bocelli's "Amapola". He soared through the scales effortlessly. Tony Bennett's "An American Classic" was a shocking revelation. If I am not mistaken, no sweetening was done on all vocals. Very bold, and very rare nowadays. With this album, you can truly appreciate how great an artist he is. I was hard pressed to identify who those other famous singers are. Simply unbelievable. I highly recommend this album. Together with Dean Martin's "That's Amore" and Frank Sinatra's "My Way", these "institutions" are shining examples in the true art of singing.

Now on with some rock. Eagles' "Hell Freezes Over" is noted for some overly aggressive "sssshhhhhh". I am glad to say that the dreaded sibilance emphasis is nonexistence. Sibilance is reproduced when it is in the recording but it sounds natural. Cymbals are delicate, not metallic at all. Bass is tight and dynamic. No boomyness and howling from standing waves. More importantly, it doesn't bleed over to the vocals.


The Cost of Performance

Are these speakers worth it? Discounting the cost of the enclosures, the Vifas and crossover components alone total to approximately $500 a pair. For this amount, one can get a lot of bang nowadays. If loudness is what you are after, these speakers are not for you. Neither will it deliver thunderous bass.

However, if you are seeking refinement, these speakers are worth some serious consideration. For this level of performance, it will cost much more than $500 in the shops.

(Figure 42)

High Pass Network

C1 = 10uF/400V Solen
C2 = 20uF/400V Solen
C3 = 4uF/400V Solen
L1 = 0.4mH 18 awg Air Core
L2 = 1.8mH 18 awg Air Core
L3 = 0.13mH 18 awg Air Core

L4 = 0.56mH 18 awg Air Core
R1 = 9 ohms/10 watts
R2 = 10 ohms/10 watts
R3 = 2.2 ohms/10 watts
R4 = 15 ohms/10 watts

Low Pass Network

C4 = 82uF/400V Solen
C5 = 20uF/400V Solen
C6 = 5.1uF/400V Solen
C7 = 33uF/400V Solen
L5 = 1.3mH 18 awg Air Core
L6 = 1.5mH 18 awg Air Core
L7 = 0.8mH 18 awg Air Core
R5 = 2.4 ohms/10 watts
R6 = 8.2 ohms/10 watts



Material = 3/4 inch MDF

Width = 9 1/2 inches
Height= 15 1/4 inches
Depth = 11 3/4 inches

Port Diameter = 1 1/2 inches
Port Length = 3 inches

Box Vol = 0.64 cu ft (18 Liters)
Box Tuning = 40Hz

(Figure 42) Final High Pass & Low Pass Network

Vifa PL27TG-35-06

Vifa PL18WO-09-08

At this time of writing, the above Vifa Premium Line drivers are still available at:
Parts Express

Speaker City


60 Downes Street | Calais | ME 04619 | USA