Akarakrit Uamkruea, blogger and audio gear maker who passionate in vacuum tube, audio & music.
Producing electronics projects since high school. Seriously upgrade and modify vintage audio equipment for “Real Sound” concept.
He is a co-founder of Soundaries, all audio solution provider.
Experienced and lively explore the listening rooms & audio shops in Japan as his most favorite to do.

Thursday, December 24, 2015

Sony Playstation SCPH-5501 as a Superb Sound CD Player Part 2

Continue from my post on last week about introduction and mainboard modification.

http://mellowgroovy.blogspot.com/2015/12/sony-playstation-scph-5501-001.html

Today I just complete assembling PS1 back after finish modify

power supply board and analog output stage.



For power supply board, I've replace all original electrolytic capacitors

with low ESR capacitors and change all diodes to ultrafast recovery diodes too.


Decoupling all electrolytic capacitors with WIMA film capacitors.


Inspiration that brought me to do this, it was article in Jeff Day's blog

about using Sony Playstation in his main system.


And after read more in his blog, I really want to hear the sound of Arizona capacitors.

http://jeffsplace.me/wordpress/?p=7528

So the sound of Playstation with combination of Arizona capacitor will be marvelous too.

I've select 0.47uF C50309 Blue Cactus version and made T-Network that attenuate

from 20k Ohms (for get high pass filter below 20 Hz)

to 600 Ohms (for match with my preamplifier).

Gain just reduce about 22 dB but can allow me to use this capacitor. That's my intention.



From using bigger capacitors in mainboard, I use nuts and washers to made a spacers on PCB.


So after assemble, enclosures will not join together but it's not a problem.


Sound of this CD player is smooth, refine, more natural and good tonal balance.

I think combination of non-oversampling DAC and Arizona capacitor are support together.

Worth a try to make and get natural sounding CD player like this.

Next step is find a wood base and ac power cord to make more stability. Cheer!!!

Thursday, December 17, 2015

Sony Playstation SCPH-5501 as a Superb Sound CD Player Part 1

DSD files or other music format are all around us for today, easy to use and good sound

But CD player with non-oversampling DAC still remind me for "Real Sound".

I already have non-oversampling DAC with TDA1541A S1,

really nice sound in my main audio system.

After read some topics in an internet, I've found many people use Sony Playstation

as a CD player and get benefit from non-oversampling DAC inside. 

So I need another compact CD player to use for living room and choose PS1.

Many website and DIYer favor PS1 with SCPH-100x series 

because it already has RCA connectors and prompt to use without any modification.

But SCPH-5xxx series can find frequently and I do not want to use opamp stage inside,

so SCPH-5xxx series is easier to modify except it has less information than 100x series.

From both websites below, I've got many ideas to apply with 5xxx series.




After remove top cover and laser unit.


Original power supply.


Many electrolytic capacitors that need to remove and replace.




Previous owner change coupling capacitors for audio output stage. :)


Mainboard before modify.


And mainboard after modify.





Bring audio signal from DAC chip with WE wires to external coupling capacitors.


Next step are modify power supply board, install coupling capacitor and RCA connectors. 
Cheers !!!

Wednesday, December 2, 2015

Inside Marantz Model 7 Preamplifier Before Modification

Marantz model 7 still the one of best preamplifiers in golden era of analog recording.

Smart functional design from phono equalizer to last stage.

Marantz used finest components at that time,

made model 7 sound very good and familiar with music lover.

This unit has serial number 7-21777, it use Sprague Orange Drop capacitors

more than another Model 7 that I ever seen from Google. ;)

This might be repaired some points from the past and still promptly use.

But I need to replace components in signal path, power supply

and tuning some component's value to make Model 7 has more natural sound.

These photos below are current status before modification.

Will compare shot by shot again with improvement list and result.



















Tuesday, November 24, 2015

Prepare Deck for Reel Tape Playback with "Tape Head" Feature in Vintage Preamplifier

Many top class vintage preamplifiers almost have "Tape Head" amplifier

with NAB equalization to use for commercial reel tape and cassette tape.

But some owners of those preamplifiers used to test or taste.

I will get some vintage preamplifiers to renovate and modify,

so I want to hear a sound of tapes from them too.  


I already have Technics RS-1700, 4 track reel to reel tape player and recorder.

But I kept it for a long time and some parts need to replace for promptly use.


Just order this service kit from ebay.

This set have 4 x brake pads, 2 x rubber belts for counter, 2 x bearing balls for tension arms.


First open back cover and remove capstan motor.



See 2 counter belts inside.



Remove reversing roller for take old counter belt out.


With new tighter belt.


Current tension rollers with corrosion. ;)



New rollers in their positions.


These brake pads are "must" need to replace.


Already remove and clean.


Use rubber adhesive glue for this job, match with vinyl and leather.


Replace with new pads.


Modify connectors to get direct signal from tape playback head.


Need to check and calibrate other points before using.