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Discrete transistor line amplifier stage
Over the last couple of years most of my interest in audio has been with transistors. I've been slowly teaching myself to read and understand the circuits. Circuits like this one for example. Not hard,...
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Discrete transistor line amplifier stage mod 1
Changed the collector load on the voltage amplifier stage to a current source (Q3), as per the Marantz SR2285B circuit. Also increased the resistance of the feedback connection, R6+R8, there seemed to...
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Szekeres Headphone Driver, distortion simulation
I've always enjoyed the sound of the Greg Szekeres' Headphone Driver (buffer) and derivatives sharing the MOSFET source follower output stage. I've often wondered however, whether it's distinctive...
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J-Mo Mk. II vs. Szekeres, distortion comparison
Two headphone amplifiers sharing the same basic MOSFET source follower output stage. When the source current and source resistance are optimized for the given headphone load and similar maximum output...
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Audacity sucks.
Under windows at least, Audacity is unable to record audio at bitrates above 16 bit. It will seem to, all right, but the data is quantized at 16 bit (30 microvolt LSB), regardless of the settings...
View ArticleWhich soldering station should I buy?
Thinking I should get a new soldering station. I've had my eye on a Weller station for the longest time, but put off getting one for one reason or another. Looking at the selection, I think the choice...
View ArticleA catalog of headphone amplifier circuits.
Lots of circuits out there, but most are variations of a small set of archetypes. Let's see if I can put together a list: 1. Dedicated headphone amplifier IC. e.g.(lme49860) 2. Battery powered, single...
View ArticleHeadphone amplifiers: thinking aloud
The sobering fact is that the built-in headphone jack on most modern consumer electronics provides pretty decent performance. Taking that output and routing it through an external headphone amplifier...
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Circuit O' The Day : A headphone output buffer.
Experimental : For Research Use Only It's bring-your-own-voltage-gain. This output stage is a unity gain buffer. A sort of diamond-buffer-meets-sziklai-pair hybrid. It lets the driver pair bias the...
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Hakko FX-888 : ebay unhappiness
Oh, for Heaven's sake... Just got the FX-888 soldering station I bought on ebay. It does not power up. Do you know why it doesn't power up? So glad you asked... It does not power up because - pause for...
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Hi-end audio, as seen from outside the bubble.
In early May Trent Wolbe traveled to the High End trade show in Munich, Germany. This is part one of a two part series exploring the cutting edge of audiophile technology. By Trent Wolbe, writing for...
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Another diamond buffer variant
Browsing through an old issue of MJ (No. 1076), I found some sketches of the Marantz SA 11S3 SACD player analog circuitry which seemed interesting. The are two discrete op amp "modules", one is used...
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The Pentamond
A rainy and cold afternoon here in Kyoto. The mind turns to audio circuits... headphone amplifiers... diamond buffers... This is an answer to the question of how you scale up the basic diamond buffer...
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Marantz discrete op amp (line stage or headphone amp)
Last one for today. I was having problems getting this to work, the key seems to be adjusting R6 to null the voltage offset. Works fine now, but this is just a rough reverse engineer of the diagram,...
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Sapphire Headphone Amplifier rev. 2.0
Original here, diyaudio thread here. November. That time of year for finally getting around to advancing some of my audio projects a little. The Sapphire has remained in "rev 1+" for some time now,...
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Upgrading the Sapphire headphone amplifier (photos)
Straightforward transplant. Out with the old (anyone want them?) in with the new. Re-used the OPA134 op amp and my dog-eared pair of 0.47uF Multicaps. On powering up I discovered that with the...
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Hakko FX-950
Earlier this year I had a really, really bad experience attempting to get a new soldering iron. This time around I made my purchase through a reputable Japanese online retailer, and am now the proud...
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A "music cafe", Kyoto.
A small corner of audio heaven, for anyone willing to pay the 500 yen cover charge. Attached Thumbnails Attached Files
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Voltage Regulators for Line Level Audio. Part I : Zeners
This is the first of a series, where I will be investigating the output impedance and ripple rejection of various voltage regulator circuits using LTSpice. Today, for the first "lesson" (I'm teaching...
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Voltage Regulators for Line Level Audio. Part II : The Pass Transistor
Part 2 of a series. Instead of pulling the output current through R1, we add an npn pass transistor, Q1. The output current now "passes" through the transistor, while the Zener diode still regulates...
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