Is it all in your head?

Greetings everyone :-)
I was a bit confused with the way AIWA presented their Heads. Many times I saw different definitions like; HX Head, Amorphous Head, Narrow Gap Head, etc. Very confusing, so I have decided to solve this tech riddle and to share the results with anyone who is interested.  

The World of Personal Stereo Hi-End Heads

Tape heads are the main sound element in every tape deck or portable stereo. The head has to have the capability of reproducing a wide range of frequency responses in the sound spectrum. Then it is up to the amplifier to translate and reproduce the quality of the sound. A high-quality head needs to be durable enough to last a long lifespan of use.

Good Ferrite heads used to last a very long time, provided that you use high-quality tapes. Low-quality ferric oxide tapes are one of the most likely types to do damage. Ferrite is high permeability a ceramic material, not like an alloy, not unlike most other head materials. 

AKAI had their own special version of Ferrite heads which they called glass and crystal Ferrite. The housing of these heads was made out of glass, but they had Ferrite cores laminated into them.

AKAI's Super GX Head; Crystal & Glass Ferrite head

Permalloy heads were extremely soft and would develop groves pretty quickly. Most low-end decks almost always featured the plain Permalloy heads. Permalloy is an alloy that consists of roughly 79% nickel, and 21% iron.

Kenwood CP-G5 Standard Permalloy Head

Some decks like Nakamichi's "Crystal Permalloy" heads were surprisingly hard and lasted extremely well.

Nakamichi Dragon; Crystal Permalloy Head - hard combination

While most manufacturers used either Permalloy heads or some proprietary variation on Permalloy heads. These heads wear fairly quickly but can be easily resurfaced.

Aiwa's DX Head; Combination of Permalloy & Epoxy 

Sendust heads had great magnetic performance and were harder than most Permalloy heads, and generally lasted much longer than average. Sendust is a high permeability metallic Alloy made out of some ratio of Iron, Silicon, and Aluminum.

Pioneer CT-F800 Sendust Head (notice the groves on the head surface)

Amorphous Heads were the latest technology back in the 80's they are supposed to wear slower and last longer than any other type of head. Also, they have clearer highs and greater dynamic range than other head types. Many of the head manufacturers switched to amorphous heads.

Amorphous heads usually last longer than Sendust heads, and that means much longer than any Permalloy. Amorphous materials are supposed to be harder than are similarly composed crystalline materials too.  Laser amorphous heads were cut with laser precision, for better surface contact with the tapes. Without the laser, it is extremely difficult to cut an amorphous material with precise accuracy.

The exception to that is the famous AKAI GX heads that were made from X'tal & Glass combination. According to AKAI, they should last just about forever, and they don't groove like straight Ferrite and Permalloy heads. Therefore AKAI gave a 15 years warranty just for the head itself.

Akai's GX Head; Crystal & Glass illustration

The Golden Years of AIWA

As the leader in Personal Headphone Stereo, AIWA introduced In March 1989 their first Amorphous Head followed Panasonic's AX Amorphous Head RX-S40, RX-S41, and RX-S45 (1984) and then the FG Amorphous Head (1989). Also Sony's WM-D6C (1984) and later on WM-DC2 (1985).

Panasonic's RX-S40; AX Amorphous Head

There are 3 versions of Aiwa's Hi-End Heads and they are only found on IC Logic Control units.

1. Amorphous Head.

2. Narrow Gap Head.

3. HX Head - Hyper eXtended Bass Head.

Amorphous Head "PX303A (PX30, PX900) features an amorphous head, often found only in audiophile cassette decks, for a remarkable improvement in playback fidelity. Amorphous alloy displays exceptionally high maximum magnetic flux density, outstanding signal linearity, and minimal noise generation. Add to this a remarkable hardness for extra durability and you have one of the finest heads available". (From Aiwa catalog 1989)

HX Head "The HX head featured in the HS-PL303A uses a slightly peaked contact surface to achieve greater signal linearity, particularly in low bass frequencies, for clearer, more accurate signal reproduction". (From Aiwa catalog 1989)

The Legendary PX303 was the first AIWA portable stereo to have the triple features combination head; Amorphous-HX-Narrow Gap Head. Later Amorphous Heads were just plain Amorphous or a combination of Amorphous & HX heads. The last one AIWA developed and upgraded to a better version of V1.0 which was a Narrow Gap Heads.

    AIWA's PX303 Amorphous-HX-Narrow Gap Head

At Later years AIWA manufactured a combination of different heads in selected models like:

• Amorphous Head found only on JX707, RX70, and PX1000.
• Narrow Gap Head found on the PX20, JX505, JL505 PX303, PL303, PL55 (V1.0), and TP38.
• Combo: Amorphous - HX Heads Found on JX3000, JX2000, PX303, PX505, PL50, RL50, and RX50.
• HX Head was found only on PL303, WR707, PL777, PL707, P705, and P505MkII.

Aiwa HS-PL707/HS-PL70

AIWA Introduces the Bi-Azimuth Head Alignment System

When Sanyo introduces the first Bi-azimuth in 1987 they called it "Double Azimuth". It was the first approach to design double point pins azimuth as in their JJ series. (Series 4, 5, 6, and on)

Sanyo JJ-P100 Bi-Azimuth Head System

"In addition to the small, light, good pursuit of high sound quality. High fidelity plays with a double azimuth head. The playback head adopts a double azimuth head which reproduces the sound recorded on the tape faithfully. For the Headphone stereo, It is a small high-performance mechanism. We also pursued a total dynamic quality, such as extending the playback ability of the low range using aluminum for the voice coil" (Automatic translation from Sanyo's Japanese Catalog 1988)

Aiwa followed with their own simple concept of Bi-azimuth Head Alignment; "This new feature automatically compensates for head alignment inaccuracies which are common to auto-reverse tape drive systems with fixed heads. When the tape reverses direction, its position shifts slightly, causing a shift in azimuth, the relative angle of the tape to the head. In either tape direction, absolutely precise azimuth alignment is essential for optimum response, particularly in the high frequencies. To assure this, the Bi-azimuth Head Alignment automatically adjusts the head to the proper position relative to the tape in each direction. Bi-azimuth Head Alignment is found on selected higher-priced models" (From Aiwa catalog 1989)

Bi-Azimuth found only on JX303, JX30, JL30, RX30, TX303, RL30, PL303, PX303, JL50, JL505, F50, and TP38. Also found on early versions of JX505, JX50,  EX500, EX50, and JX2000. (For example, the old AIWA logo version JX2000/JX505 had Bi-Azimuth. on the new logo, the Bi-Azimuth is gone. See the attached photo's)

Sony also tried to get a different approach and invented the world's first portable stereo with a double heads design the WM-EX909/FX909 (1992) it was an expensive approach but it was leaving everyone else far behind with their plastic mounted heads and a poor degrading sound.

Sony's WM-EX909 Dual Head Concept

Even though Sony was the "inventor" of the Walkman they fall behind AIWA in many categories. Sony tried to compensate for that by acquiring AIWA in 1992 which led AIWA - the best personal stereo leader to their sad end. But no doubt, Sony Walkmans were built to last longer; this is still Sony's greatest advantage even nowadays.

Be Good :-)

TheLion

This article was first published on the old Stereo2Go Forum, June 2011

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