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The cost of hi-end audio: is it worth it?

Posted 20th December 2011 at 06:16 AM by rjm
Updated 20th December 2011 at 06:30 AM by rjm

Having recently actually bought some new (not used, not my own design, and relatively expensive) audio gear, and from 47 Labs no less, the following question has been occupying my thoughts of late:

How much would you pay to not have a component installed in the audio equipment you buy?

The traditional price scheme for audio equipment is [BOM-times-X], where BOM is the cost of the parts used to make it, and X is a multiple to cover fabrication and distribution costs, as well as profit for the various parties involved. My understanding is that for consumer audio "X" is about 4, though companies with strong brand recognition can get away with higher multiples. And do.

The basic problem is this: how much it costs to build and how good it sounds are not the same thing. There is some correlation: a large, high quality transformer is pretty much guaranteed to improve the sound quality, but for the rest, stuffing a pretty box with many cheap...
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Old

47 Labs "Treasure" 0247 shipping update

Posted 20th December 2011 at 12:19 AM by rjm

Scheduled to be delivered tomorrow evening!
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Fascinating: SMT attenuator retrofitted into ALPs case

Posted 17th December 2011 at 03:08 AM by rjm

http://www.icl.co.jp/audio/att.htm

Less than 3,000 yen, too. Pity it's only available as 100K types, but for tube amps this is a pretty handy little part to have around.
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Old

47 Labs 0647 "Treasure" CD player diy kit

Posted 17th December 2011 at 02:54 AM by rjm
Updated 17th December 2011 at 03:01 AM by rjm

Fancy building your own CD player with built in non-oversampling DA converter from a kit?

Look no further.

Based on a TEAC transport and ye olde Philips TDA1543 for the nonoversampling DAC

DAC is basically the Progression DAC (see DAC of ther Klones) reborn.

or salient details:

-top loading, close to the lit to automatically load the TOC.
- isolated digital and analog power supplies
- ATMEL AVR microcontroller, custom program/operating system
- simple, easy to understand display and controls
- standalone or use as a transport with external DAC
- small footprint, B5 size(W250 H65 D175mm)
- comes with a remote!

Although offered as a kit or pre-built, my suspicion is that all the real work has already been done: programming the microcontroller, now that's an area where most DIYers still fear to tread!

Not too many kit/home build CD players...
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Old

47 Labs 0347 "Treasure" stereo amplifier

Posted 16th December 2011 at 12:33 AM by rjm
Updated 17th December 2011 at 02:33 AM by rjm

This is interesting.

A stereo amplifier.

Yes. Well, think of it as a bulked-up headphone amplifier. The design is one of those "ah, I should have thought of that" moments, but the details are quite tricky, as usual.

If the extend the basic "voltage stage + current buffer" topology of the 47 Labs 0147 headphone amplifier out to 40 wpc territory, you end up with the 0347.

The high power means than unlike the headphone amp design you have to run it out of class A, and that means closed loop operation.
While most people might be tempted to wrap the voltage feedback around the whole shebang, this basically ends you up with a big op amp. Op amps, with their massive negative feedback design, are not so happy driving high inductance/capacitance loads like speakers.

The trick 47 labs uses is to have two feedback pathways, with heavy "local" feedback around the op amp and a small secondary...
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Old

Other options for a headphone amplifier.

Posted 15th December 2011 at 02:02 PM by rjm
Updated 15th December 2011 at 02:08 PM by rjm

While I wait for the guys at 47 labs to get the Treasure 0247 together, I took a look around at some of the alternatives.

The Yulong D100 looks quite attractive and for about 2/3 the price of the 0247 kit you get a fully assembled unit!

review at head-fi

Or if you can do without a DAC, HLLY audio has your standard "transistor buffered op amp" implementation in a no-frills case:

HLLY RMK-5

It's listed at $240 but for sale on eBay for only $99 right now.

Of course there are dozens, but I single those two out as being particularly deserving of "honorable mentions". I'm still set on the 0247 though.
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Old

47 Labs "Treasure" Model 0247 DAC/Headphone/Preamplifier

Posted 14th December 2011 at 06:56 AM by rjm
Updated 17th December 2011 at 02:36 AM by rjm

Just placed my order for this. I am customer no. 00028!

47 Labs web page

I figure I owed it to them. 47 Labs has been good to me, and the DIY community over the years, one way or another: gainclone, phonoclone, even the DAC-of-the-Klones.

Besides, several reasons:

1. I really want to finally hear 47 labs gear, instead of trying to reverse engineer it all the time!
2. It will be interesting to compare it against the sapphire amp.
3. I'm sure it will be fun to build and examine up close.
4. It's my Christmas present.
5. And hammertone. Finish a audio product in grey, or even better, green hammertone, and its as bees to honey...

Will blog the unboxing, building, and testing right here.
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Old

RJM Audio Kits : Available ... again!

Posted 12th December 2011 at 12:09 AM by rjm
Updated 13th December 2011 at 06:08 AM by rjm (updated with price info)

Back by popular demand, I have decided to go ahead and prepare full kit version of the VSPS300, Phonoclone 3, and Sapphire projects.

10 kits of each project will be available - contact me to reserve.

Phonoclone Kit : $125 (10 availble) Set of two boards and components to populate.
VSPS 300 Kit : $117 (10 available) Set of two boards and components to populate.
Sapphire Kit : $113 (10 available) Set of two boards and components to populate.

Kits will be shipping shortly after the New Year.

Current status: necessary parts shipped from Mouser, should be able to assemble kits this weekend. Also have to prepare the documentation.

RJM Audio Kits
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Old

RJM Audio, now on Google+

Posted 21st November 2011 at 12:06 PM by rjm

I hate facebook but I'm willing to give Google+ a go. Now they have "product" pages as well as "people" pages, I have made a little port to RJM Audio.

RJM Audio Google+ page
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Old

Sapphire Desktop Headphone Amplifier Kit

Posted 8th September 2011 at 06:26 AM by rjm
Updated 10th December 2011 at 02:23 PM by rjm (add some photos)

Update: kits were sold, but another run of boards is going ahead!

There will be 10 kits available, at a cost of $100 each. The boards (rev. 14a1) and all parts for the boards will be included. Shipping is included.

Info here and here.
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