Fisher AD-Z1 CD player / Transport

Fisher AD-Z1

May 2009

This is a really special player.
This company was (I think, I may be wrong) the upper market brand of Sanyo. A Lexus so to speak.
The picture of the player send  the shiver up  my spine: WOW ! I want it!
Unfortunately - ebay worldwide haz zero Fisher players.
So - first conclusion - it is RARE.

After seeing it in reality at friend's, I was even more excited: it looks like a bolid, it is massive, heavy, with very thick wooden cheeks, golden ornaments and letters, shiny LEDS etc. It is the culmination of end-of-eighthties High End. Like Sony CDP-557 ESD, Grundig CD-9009, Kenwood DP-8010, etc.

The owner had a request to improve it as a transport, ignoring the dac.
OK, challenge taken.






Above: My all time favourite keypad ! Ideal !









Whats inside Fisher AD-Z1 ???




First - the good things:
The looks : 9/10
The button ergonomy: 10/10 !!!
The display : 8/10 (too small fonts)
Functions: 10/10
Drawer operation - FAST - reading - FAST = 10/10

Inside - the player makes first impression that there is less stuff than expected. There is just 2 PCB's and a transformer and a mechanism.
The mechanism and laser are both from Sanyo. Very interesting. Ir resembles Sony Kss151A - with magnetic rails tracking, big laser pickup, and large clamping arm. It is a pity the whole mechanism is fully plastic, unlike Sony's kss190A. And I know sanyo mechanisms and lasers are good (Shigaraki, CEC). So this may be an interesting transport.
Transformer is not too small, but only one.






This is a very nice laser pickup, but if it fails - god forbid - the owner will be in deep you know what. It is very rare and probably no more New Old Stock supplies.


The upper green PCB is a DAC - dual mono PCM58 from Burr Brown. A nice DAC but from middle class. It is not an aristocrat of DAC kingdom, worth big effort of lampization. So it is good idea to make it a transport. The DAC board can be unplugged and removed - it does NOT affect CD operation and transport SP-DIF output.



The green PC has positively a high end look and feel.

The DAC board is different than the rest of electronics - I would say - it was better made, by a better engineed with higher budget.


The green dac consumed all the premium parts of this player. Nothing was left for the lower brown board with digital part. It is like in the Titanic. Upper deck takes all the lifeboats.


After removal of the DAC PCB - what we are left with is a grown PCB with all digital circuitry.

And here my problem begins. This pcb looks really cheap and simple. No more premium parts, no neat arrangements, nothing special. This is just a cheap mediocre CD player PCB, which belongs in upper low class of players. Something like Yamaha 480.
The disproportion between the budget spent on the external look and internal engineering is HUGE. Waaay out of balance.
Obviously this series of Fischer gear (with CD, tape deck, amp, tuner) was made for  the nuveau-riche segment , not for audiophiles.




Arrow point to:
big black heatsink for ONE regulator 7805. Yes! All player - motor, laser, display, demodulator, digital filters, servo, microprocessor - ALL of them share one common supply regulator. Horror usually associated with 50 Euro players. How could they do it ?

The X sign indicates the elements of S/PDIF output which I eliminated by bypassing them. The 3 chips and the switch and Toslink - all had to go.

I installed new RCA in the hole left by the removed Toslink transmitter.

The task - Killer Transport

The stock trace looks VERY GOOD. I am surprized. It is better than most. It already sounds better than most players, including the heavy Marantz champions.

So after some tweaking - it may be even great, who knows.


Above trace is stock. After my clean up - it improved but very slightly. I have no photo.


Looking at the schematics - I see the digital S/PDIF signal going from the source - Yamaha chip - to the output - via 3 other chips, a switch and a transformer.

My plan:
1. To find the s/pdif source.
2. To install new  RCA socket for s/pdif
3. To upgrade power capacitor to the chip which producxes the s/pdif signal
4. to bypass all circuitry between s/pdif source and the output RCA.
5. To install superclock.

Later, we may decide to add a power sixpack  just like in Fikus Transport 1,0 and feed EVERY chip and function from separate regulator.



This is the key chip Yamaha YM3613C  - the one which forms biphase output called S/PDIF (digital output to DAC)
Bingo ! I found the perfect trace on leg 7th.




The small red arrow points to the pin number one which is +5V power input. The new OSCON will be sitting on that input. There is only that green ceramic there so I bent it slightly and soldered the oscon SEPC series as a bypass of this green ceramic cap. Minus leg of the oscon - closer to DAC.


Blue wire takes directly the digital signal to the RCA. Yellow wire catches the nearest ground point on the PCB. There is no more galvanic insulation of the s/pdif. It is direct.

The Yamaha makes a hell of a signal - very clean indeed. It was too high though - 5 Vpp. So I added a parallel resistor of 75 Ohms which took the signal down to below 1V. After the load of the DAC 75 Ohms again, the signal will be a perfect 0,5 Vpp as should be.


s/pdif in fisher CD

New RCA with 75 ohms in parallel. Later the resistor was cut to be short and neat.

CLOCK


I installed a Polish made clock MRelektronik from Lubin with OMIG 5ppm resonator and own power supply and own transformer. The clock is 16,9 Meg like all Japan players.

On the below photo you see the quartz which I removed and two caps and one resistor. The new clock has its output directly connected to leg 3 of the chip74HCU04.




The result:

1. The player WORKS. Without the DAC  board, witthout s/pdif forming chips (de-forming)  3 of them succesfuly omitted.
2. The sound is slightly better. It is not a night and day difference but every aspect is a little bit better. Well worth trying.
After my mod of SP/DIF bypass - the DAC would not play anymore - so beware - if you do this - no more analog outputs.
On the other hand - this DAC board can be recycled and used as standalone DAC with good own supply.

 

 
Parts for this project