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The New Shohin “Can” Amp w/OPA627BM

The New Shohin will soon be available with the higher end can version of the BurrBrown OPA627, the OPA627BM.  With it’s Dual-Mono amplifier topology, high end thin film resistors throughout, 20Vpp power supply and dual “high performance, hifi, high current headphone buffers” this is one killer headpone amp that takes advantage of the additional performance of […]

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Vacation Time!

I will be out on vacation from June 30th through July 20th and will not be able to ship or build amplifiers during this time.  If you’d like to order an amplifier before I leave, please place your order this week, before June 20th, so I can have time to build your amplifier and have […]

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The Portaphile V2, V2^2 and Maxxed Upgrades

I recently had a customer send in a Portaphile V2 for some repair work and while it was in the shop I decided to offer him an upgrade path.  The original Portaphile V2, V2^2 and Maxxed versions all share a very similar amplification section as the current lineup (627, MICRO and 627X), the main difference […]

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Portaphile NOK aka “Nude Overkill”

Well, I thought I’d let out some more info on the upcoming Portaphile NOK.  The NOK is short for “Nude Overkill” and without going too much into the specifics yet I’d like to disclose that the overkill comes from some upgraded parts that some out there would consider to be overkill for a portable headphone […]

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Coming soon! New Flagship: The Portaphile NOK

I am currently working on a new amplifier that is going to be my new Flagship amplifier.   My current target price point is going to be just under 1K.   It’s still in the design phase but I am hoping to be able to get it out in 6 to 9 months.  I will […]

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Portaphile’s Loyal Customer Discount

If you’ve purchased one of my amps before, whether from me or someone else, contact me about getting a great discount on one of my new amps.  I will need to verify that you’ve ordered an amplifier before either through my order history or some other way if you currently have one of my amps. […]

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Shohin’s dual Mono Amplifier Architecture

One of the things I’ve failed to mention about the Shohin’s amplifier design is that I’ve followed a dual mono approach in keeping each separate from one another.  BUT, I don’t like to advertise it as dual mono because for TRUE dual mono you need two separate power supplies and in a portable amplifiers that’s […]

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What’s in a Portaphile, Part III (Or what’s not….)

No capacitors in the signal path.   The bottom line is that putting capacitors in the signal changes the sound.  I don’t care how good or expensive the capacitor is, putting one in the signal path will alter the frequency response in some way.  Read up on it and you will commonly find terms such […]

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What’s in a Portaphile, Part II: 0.1% Metal Film SOIC Resistors

All Portaphile amplifiers are built using strictly Metal Film SOIC resistors inside the amplification circuitry that have a 0.1% tolerance. Resistors come in different tolerances such as 20%, 10%, 5%, 1% and 0.1%.    What the 0.1% tolerance means is that the resistor is rated by the manufacturer to vary only +/- 0.1% from it’s stated […]

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What’s in a Portaphile Amplifier? Part 1

I will begin a series of post highlighting some of the inner workings of our amplifiers.  First, let me introduce TKD, or TOKYO KO-ON DENPA COMPANY LIMITED  .  Here is an excerpt from the company’s website: “Tokyo Ko-on Denpa Co., Ltd. (hereinafter cited TKD) was established in 1944. Since then we have been manufacturing attenuators, faders, precision […]

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