2016/07/25 created
2021/05/07 updated

The contents of this page were reprinted from the previous homepage of mine, 'Tonochi's Audio Room'. Some parts were edited.

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I have been developing my audio system Gaudi since 1974. In September 2015, it was completed at last, as the midrange amplifier MA-215 Arabesque was completed.
I determined the completion of Gaudi though it is a bit different from the original system design (the preamplifier and all the power amplifiers were tubed type), because all the amplifiers used in Gaudi are my works now and the sound quality (SQ) has reached at the level that I aimed at in the first place.

Another major difference is the digital player. I replaced the SACD/CD player, SONY SCD-555ES, with an HDD player, SONY HAP-Z1ES. I think optical discs like CD and SACD are old-fashioned now in all aspects such as SQ, usability and cost.

The configuration of Gaudi has turned to be as shown in the diagram below:
[Block diagram]

The power amplifier MA-215 Arabesque lives up to my expectation. It improved SQ of Gaudi further, and its musicality is so good.
However, I know Arabesque has some shortcomings to improve from the results of measurements and listening tests (for detailed information, see the page of Arabesque). It's a natural consequence because Arabesque is my first solid state power amplifier.

As for SQ of Gaudi, I've expressed it by the wording "nearly high end" in this website for recent years, but now I am convinced that difference between "nearly high end" and "truly high end" is so big. Say, every time a shortcoming is removed, another one appears soon. I believe Gaudi still has some challenges to solve in order to realize truly high end SQ.
I'm planning to analyze the shortcomings of Gaudi and design Gaudi II based on the analysis. I believe my dream will come true with Gaudi II.

HAP-Z1ES (HAP) didn't live up to my expectation. Before evaluating its SQ, I was annoyed by its mechanical noises produced by the cooling fan and HDD. I had never heard of an audio device that produces a mechanical noise. And the list price of HAP is as expensive as 210,000 JPY. I owned two other A/V devices (digital recorder: KORG MR-2000S, STB: Panasonic TZ-HDW611P), and they don't produce any mechanical noise. The HAP is my fifth one in Sony's ES series, and I was happy with the previous four. It was the first time I was disappointed with the ES series.
I was surprised when I saw the inside of HAP. The HDD is 2.5 inch type, instead of 3.5 inch silent type. The fan is not silent type either. The layout looked like one for IT equipment. I can't believe it was designed by (an) audio engineer(s). Maybe, (an) IT engineer(s) did.
I was not aware of this problem when I auditioned it at an audio shop, because of the ambient noise. My house is located in a quiet residential area and has good acoustic insulation, so it is quiet in the room at even a day time. The mechanical noise from HAP can be heard at any place in the room.
Before I bought HAP, I check out user reviews on Internet. Almost all the reviewers gave it five stars and no one reported this problem. Besides, some audio magazines recommended HAP. So I didn't expect this problem.

I quit using KORG MR-2000S as a digital player. I use it only when I digitally record vinyl discs. HAP is better in SQ than MR-2000S even though it has the noise problem. Besides, a smart phone can be used as a remote of HAP with an APP (HDD Audio Remote). So HAP is much better in usability.
I confirmed the effect of DSEE, Sony's proprietary technology to upgrade lower bit rate music files. When a CD quality WAV file is played with DSEE activated, it nearly sounds like a vinyl record. Especially, in case that the original recording is analog, DSEE is more effective.
The mechanical noises aside, HAP has good SQ. I would like to replace the HDD with a SSD for silent operation in some day in the near future.

I am considering replacement of the analog disc player too. At the beginning of this year (2016), I bought Pioneer PLX-1000 and have been testing it till now (July). I admit it excels my old player PS-104 in both SQ and usability, but I stick to PS-104, which I built when I was a university student and have used for the past 34 years. I can hardly abandon it.

One more change. I replaced the PC and the player program to improve SQ of PC-based audio.
The new PC is Panasonic Let's Note. Its CPU is Core i5. It is so powerful for a small laptop PC.
The player program Audio Gate is upgraded from the Ver. 3 to Ver. 4. The Audio Gate 4 needs a powerful CPU. It causes an error on my previous PC, Lenovo ThinkPad. It runs on Let's Note without any problem.
SQ is much better. It is close to that of HAP. I felt again high performance of KORG DS-DAC-10.
However, Let's Note causes mechanical noises of the fan and HDD. It is a catch for listening to music. I think the problem will be solved by replacing the HDD with SSD.

Equipment

Category	Model	Features	Description
ADP	NOBODY PS-104	*Turntable: SONY TTS-8000 *Tone arm: GRACE G-1040 *Cartridge: audio-technica AT33PTG/II	I've been using it w/o major modification since 1982. I changed the cartridge from MM type to MC type in 2014. I am considering replacing it with Pioneer PLX-1000.
MC head amp	NOBODY HA-213	Head amplifier for MC cartridges Gain = 30dB	This amplifier was designed as a headphone amplifier at first. Before completion, it was re-designed as the MC head amplifier. Though its design is not perfect, a certain level of sound quality has been achieved.
DAP	SONY HAP-Z1ES	HDD player w/ built-in 1TB HDD	PCM: up to 192kHz/24bit DSD: up to 5.6MHz I bought and installed it in 2015.
DAP	Panasonic Let's Note CF-N9	11" laptop PC	Storage: 250GB SSD. The combination of this PC and DS-DAC-10 functions as digital audio player. It also functions as a measurement instrument w/PicoScope and PAA3.
DAP	KORG DS-DAC-10	USB DAC	The combination of this device and Let's Note functions as digital audio player. The player program is Audio Gate 4.
DAR	KORG MR-2000S-BK	1-bit digital recorder	Digital recorder for studio use. It is also available in the retail market. The highest resolution is PCM 192kHz/24bit and DSD 5.6MHz. It is used for recording vinyl discs.
Preamp	NOBODY PA-210 Simplicity	Tube preamplifier All stages are SRPP CR-type phono equalizer Non-NFB flat stage Separate power supply	A tube preamp made in 2001-2003. Featured by out-and-out simplicity and low noise.
Network	NOBODY CD-211B A-NET	Solid state Three-way channel divider (network)	The first NOBODY-branded model that uses op amps. Made in 2004. Rev. A in 2012. Rev. B in 2015. Crossover frequencies: 800Hz(18dB/oct), 6800Hz(18dB/oct)
Tweeter amp	NOBODY MA-208	Tube power amplifier 6BQ5 UL PP	Designed for horn-loaded tweeters. Made in 1999. Split load phase splitter; rectifying tube. Output power: 10W+10W
Midrange amp	NOBODY MA-215 Arabesque	Chip power amplifier IC: LM3886	Power amp for midrange, made in 2015. Its sound is clear and transparent, with very low output impedance. Output power: 1W+1W (8ohm)
Woofer amp	NOBODY MA-201C	Tube power amplifier 6CA7 UL PP	The first NOBODY-branded equipment, made in 1974. Used for woofers. The current revision: C Output power: 30W+30W
Loudspeaker	NOBODY SS-309A	Three-way speaker system *Tweeter: Fostex T925A *Midrange: Fostex D1405+H400 *Woofer: Fostex FW305	12" woofer-based three-way loudspeaker, made in 2001. It doesn't include network and attenuator since it's designed for the multi-amplifier system. Vented box for woofer. The midrange unit was changed from full-range direct radiator to horn-loaded midrange in 2012 (Rev. A).
Pnono cable	PS-104 -> PA-210	GRACE genuine cable (RCA plugs has been replaced)	Low capacitance cable using LC-OFC. In 2011, the RCA plugs' solder joints corroded and the cable was disconnected. The RCA plugs were replaced with new ones using PTFE insulator. Sound quality has been a bit improved.
Line cable	HAP-Z1ES -> PA-210	Handmade cable *Wire: BELDEN 8412 *Plug: Teflon RCA plug	Handmade cable made of balanced type shield wire. Though the RCA plug is a generic one, the insulator material is teflon. The plug's metal cover is not attached. Shrink tube is applied instead.
Line cable	PA-210 -> CD-211B	Handmade cable *Wire: BELDEN 8412 *Plug: Teflon RCA plug	Handmade cable composed of balanced type shield wires. One end of the cable is soldered in CD-211B.
Line cable	CD-211B -> MA-208	Handmade cable *Wire: BELDEN 8412 *Plug: Teflon RCA plug	Handmade cable composed of balanced type shield wires. One end of the cable is soldered in CD-211B. The wires were Audio Technica AT6A48 when CD-211 was built (2004). They were replaced with BELDEN 8412 in 2008. BELDEN is unquestionably superior. The metallic cover of the plug was replaced with a thermal shrink tube.
Line cable	CD-211B -> MA-215	Handmade cable *Wire: NEGLEX 2549 *Plug: Teflon RCA plug	Handmade cable composed of balanced type shield wires. One end of the cable is soldered in CD-211B.
Line cable	CD-211B -> MA-201C	Handmade cable *Wire: BELDEN 8412 *Teflon RCA plug	Handmade cable composed of balanced type shield wires. One end of the cable is soldered in CD-211B.
Speaker cable	MA-208 -> SS-309A tweeter	Handmade cable *Wire: 47 Laboratory STRATOS *Plug: none	Handmade cable made of 0.4mm copper single wires twisted at 30cm pitch. One end of the cable is soldered to the output terminal of MA-208. The other end is plated w/ silver loaded solder.
Speaker cable	MA-215 -> SS-309A midrange	Handmade cable *Wire: audio- technica AT365S *Plug: none	Handmade cable made of Audio Technica's entry class OFC wire. The both ends have no connector and coated with Titan Audio Oil.
Speaker cable	MA-201C -> SS-309A woofer	Handmade cable *Wire: 47 Laboratory STRATOS *Plug: none	Handmade cable made of 0.6mm copper single wires twisted at 30cm pitch. One end of the cable is soldered to the output terminal of MA-201C. The other end is directly soldered to the terminal of woofer.
Room		25m2 living room	Fairly soundproofed. Slightly live at mid and high frequencies and slightly dead at low frequencies. Almost no standing waves thanks to the slant ceiling. Acoustics is tuned by using acoustic panels, sound absorbing panels and sound absorbing curtain. Equipped with outlets for audio equipment; both 100V and 200V. The sockets are for medical use.

 

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