Goodmans Axiom 301 Speakers
Close to what the Axiom 150 mkII would look like new.
Goodmans Axion 150 mkII, 16 ohms. Assembling the speaker again is tricky business as the magnet gap is very narrow, 1 millimeter. I've tried setting up a two-way system with the Axiom bass and Wharfedale Super 3 tweeter with a point of crossover around 5-6 kHz and got a reasonably flat response. The sound wasn't bad at all. Goodmans goodmans industories ltd. 1952（昭和27年） axiom 80 24cmフルレンジスピーカーユニット ￥26,500 神格化された 異端の名作。 このユニットを真っ先に目をつけ、自家用としたのは、 弱冠22歳の瀬川.
The whizzer cones were removed from the drivers.
The whizzer cones are made from some heavily impregnated rigid paper
and a fabric dust cap was glued to the throat to protect the voice coil.
Measurements
TS-data after restoration of surrounds and recentering of voice coils. Now, a BL factor of 20 is not an everyday sight and these drivers are extremely sensitive. Calculated 97 dB/1W/1m. And measurements confirm this. |
Original Goodmans data.
Two things from the above LspCAD modelling: The Speaker Unit Editor is a great feature allowing you to check your measurements by cross calculation. As can be seen there's a good correlation between data. My Tannoy test cabs will serve as initial cabs for these drivers and a decent alignment can be a achieved giving a good response down to 50 Hz. 150 liter would take the response down to 40 Hz, but these drivers will be tried in an open baffle construction. Preliminary 'test' can be seen below. |
Left: The impedance curves tell a lot about driver performance. As can seen, the Fs of the restored drivers are fairly good, but compliance of suspensions are not exactly the same, one driver having a more narrow impedance peak compared to the other. All the ripples on the graph reveal suspensions not working properly, but it's been seen worse, much worse. |
Frequency response of two drivers in test cabs, quite nice.
Reading normalised for 2.8V at 1 meter distance.
Sensitivity = 96-97 dB/2.8 V.
The following three graphs were made in LspCAD just to get an idea of how easy - or difficult - the Axioms would be in more conventional applications. Above modelling for a potential two-way system with a point of crossover around 2.5 kHz. I've tried setting up a two-way system with the Axiom bass and Wharfedale Super 3 tweeter with a point of crossover around 5-6 kHz and got a reasonably flat response. The sound wasn't bad at all. Having some 550 cm^2 cone area for midrange is special and the transient capability of these drivers is phenomenal.
Above modelling a point of crossover around 800 Hz. A fairly smooth decline of the Axiom response is seen.
The minor notch at 2 kHz can easily be handled by by-passing L1011 with an RC circuit.
Goodmans Axiom 301 Speaker System
Simulation of a 3-way system with the Fostex FE126E for mid and
Wharfedale Super 3 for treble. Doesn't look bad at all.
Here's my open baffle test made from whatever I had at hand in my workshop.
Taking the Axioms down to floor level and getting decent room-gain is special.
The bass may not go deep, but you have the feeling of extension all the way down.
Running the Axioms full-range and playing Nils Lofgren/Acoustic Live is chocking.
You get a feeling of having never heard the dynamics of the recording before this.
Goodmans Axiom 301 Speakers
So much on the Axiom 150 mkII drivers.
Goodmans Axiom 301 Speaker Problems
Goodmans Axiom 301 Speaker Review
Go to: OB7, Axiom 150 mkII in open baffle experiment.