My boring digital life
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| Tascam DA-P1 courtesy of pgr.tv |
Probably the most significant digital audio gear I ever owned was the Tascam DA-P1 DAT recorder. This machine recorded my recitals, chamber music performances and served as a back-up and playback deck for my CD projects from the mid 90s until the early 2000s. It was rendered obsolete when HD based recording became the industry standard.
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| DAC in the Box courtesy of Wiki Commons |
I never invested in a high-end CD player. The most I ever did for CD playback was get an Audio Alchemy DAC in the Box fed by the digital output of a consumer grade Philips CD player. When the Philips CD player conked out in the early 2000s, it was replaced by a Sony DVD/SACD player.
Line transformers as Digital Sound Processors
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| Tamura line transformers |
Ever since I inserted a pair of Tamura 600:600 line transformers as a digital sound processor (DSP) between the CD player/DAC and my preamp line inputs, I didn't see the necessity of upgrading the Audio Alchemy DitB. I don't know if this holds water but my empirical rational for this is, magnetic coupling filters digital artifacts and RFI noise from the DAC output, which is manifested as harshness to my ears.
Art Dudley Listening
If I don't consider the few issues of Stereo Sound Tube Kingdom and MJ I picked up in Tokyo in 2015, it's been a long while since I subscribed to, let alone bought, a single issue of Stereophile, The Absolute Sound or any audio magazine. After the demise of Sound Practices in the late 90s, the only audio magazine I read was Art Dudley's Listener.
Although I've never had a chance to meet Art personally, I know he is a fine gentleman. I've been following his Stereophile column online and he has given credit to my musings on the open baffle as well as the Altec 755A. He even sent me a private message when my father passed away earlier this year. I was looking forward to meeting him at the Capital Audio Fest 2017 but missed the event because it coincided with the Harrisburg Symphony's November Masterworks.
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| iPad mini + UTC A20 line transformers |
Due to my current location, access to quality FM programming is practically nil. I've relied mainly on digital streaming via iPad mini + DSP to widen my choice of free music. 😜
USB DAC
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| Audioquest Dragonfly Black V1.5 |
When I realized that the iPad mini's internal DAC can be by-passed through an Audioquest Dragonfly USB DAC, I searched the archives of Art Dudley's Listening to see if he had anything to say about the AQ Dragonfly USB DACs. After getting Art's stamp of approval, I placed an order for the cheaper Black.
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| Stereo > Mono |
Whether I was listening in mono or stereo, this was the best $100 (ok, + $38 for the Lightning to USB 3 Camera cable adapter) investment I ever made in digital audio. The degree of improvement was at least as significant, if not greater than, when I started playing with transformer DSP(s) between the digital source and my line preamp input(s).
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| Stereo set up = AQ Dragonfly Black > a pair of UTC A20 wired 1:1 > preamp line stage |
The combination of the iPad mini + AQ Dragonfly Black + DSP = smooth analog-like detail across the audio bandwidth. So I take back my word, I need this USB DAC. 😎
Thank you Art and here's to us meeting some time soon. Cheers! 🍻
Thank you Art and here's to us meeting some time soon. Cheers! 🍻
Try it with 111Cs ;)
ReplyDeleteI only have 1. 😞
DeleteHi Je,
DeleteHow do you wire the UTC a20 into 1:1 or 600:600ohm? from looking at the diagrams on the primary side 1 is +, 6 is neg, join 3&4. On the secondary side 7 is +, 6 is neg, join 9 and 10. Where do you wire the ground lug of the transformer? thanks
DeleteGround terminal is not connected and I followed this diagram: http://www.mzentertainment.com/technical_archive/utc_a-20_transformer_impedance_connection_diagram.gif
I don't have problems with buzz/hum/noise, but YMMV.
Hope this helps!
JE
Hello
DeleteWhat kind of line transformer was show on stereo to mono picture?
Altec 15356
DeleteHi, I saw such a connection.
ReplyDeleteTell me, who knows how to properly enable 600: 600
http://zozosir.blogspot.com/2013/10/utc-a20.html
In the context of this article, I use this transformer connected as a 1:1 (500:500).
DeleteThe link you sent show/suggest different connections. It would be best if you ask that blogger since he authored that article.
JE
Hi,I want to choose Tamura transformers to build a digital sound processor like you did to use between the dac and the preamp.Besides 1:1 600:600 ohms specs, is there anything else that I look at (like dac output impedance/preamp input impedance)?I'm not not a technical person and I will rely on a technician to buil it for me.Thanks in advance for all the tips you can give.
ReplyDeleteAny modern DAC should be able to drive a 600 ohm input. Aside from Tamura there are many other line transformers from other manufacturers like UTC/TRW, Edcor, etc. Just make sure that it is rated for audio with a bandwidth of at least 30-15kHz.
DeleteHappy hunting and stay safe!
JE