DIY Audio, Hi-Fi and Music Roundup #2

Happy New Year folks and welcome to our second installment of the DIY Audio, Hi-Fi and Music Roundup.  

PARTS AND KITS

Oatley Electronics K295 Stereo Tube Sound Line Buffer Amplifier Kit

The latest kit offering from Oatley Electronics is the K295 Stereo Tube Sound Line Buffer Amplifier Kit which retails for $36AU.  The low cost, simple to construct, stereo tube buffer, lets you experience "tube sound".  The kit is based around JAN 6418 sub-miniature vacuum tubes and designed for 100-120 or 200-240V 50/60Hz AC operation.  These inexpensive tube kits can sound quite good, see Mark's review of the K272 Headphone Amplifier Kit and the recent review in audioXpress.  Via - Mark [K295 stereo JAN6418 tube buffer / preamp kit].

Oatley Electronics K295 Stereo Tube Sound Line Buffer Amplifier Kit

Decware FRX Full Range Driver

Decware has released the 8" Decware FRX Full Range Driver for open baffle loudspeakers.  The unique driver is hand built and offers an extended ultra flat response made possible by it's electromotive coupling technology and powerful neodymium magnet.  The exotic drivers retail for $595US each.

SPECIFICATIONS	TS	PARAMETERS
95 dB with 1 watt at 1 meter Response is 38Hz ~ 25kHz 8 ohm nominal impedance 17 watts RMS Dimensions: A: 8.7", B: 7.2", C: 4.0"  D: 9.8" 1 inch voice coil machined copper phase guide 5 way machined gold plated binding posts on rear Shipping weight 15 lbs ea.	Re Fs Qe Qm Qt Le Vas  Xmax Ef Zmin Zmax	7.36 ohms 70 Hz 0.83 8.45 0.76 1.88 2.04 4.22 mm 95dB 1w/1m 7.4 ohms 72 ohms

The FRX represents an obsessive effort on my part to perfect the full-range point-source driver for Open Baffle speakers at a sane cost. While the build quality of this driver will compete with with other brands costing many times the price, I don't believe any of them will hold up sonically because of the side effects of high flux low mass designs. Side effects like the occasional shouty mid-range and forward presentation or ringing that comes with the  tipped up response that is characteristic of these types of drivers. The FRX overcomes these side effects with a unique motor assembly that uses electromotive coupling between the amplifier and the voice coil. There is no other single driver in the world with  this technology.

I personally hand build these drivers to order. Build time on a pair of these fine drivers is 6 to 8 weeks.

-Steve Deckert

PROJECTS

Solo 103 Build with Fostex FE103En

Kris at HIFI ZINE has tried out the Solo 103 enclosure with the new Fostex FE103En driver.  The Solo 103 enclosure was originally meant for the Fostex FE103  (a.k.a. ACR FE103) and there have been many positive reports with the more recent Fostex FE103E.  For full impression of the Solo 103 speaker with the new Fostex FE103En drivers see A Solo 103 Build.

Solo 103 Build with Fostex FE103En

ECC802S Tube SRPP Preamplifier
Bruce of OddWatt Audio has shared with us his ECC802S tube SRPP preamplifier design. The preamplifier uses a solid state power supply and DC is used for the heaters. The gain of the preamp can be set at 7 or 11. 12AU7 and ECC82 tubes can also be used.  For more information about this project, see the DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier.

ECC802S Tube SRPP Preamplifier

NEWS

There is a new annual audio and video show in Toronto, Canada.  The Toronto Audio Video Entertainment Shows (TAVES) will be holding it first annual consumer audio, video and electronics show in Toronto in 2011.  The show is scheduled for September 30 to October 2, 2011 at the King Edward Le Meridien.  For more information, see the TAVES website.

MUSIC

HDtracks Offers Select Titles with 24-Bit/192kHz Resolution 

HDtracks is now offering select titles in full 24-bit/192kHz resolution. The currently available titles are Jen Chapin - reVisions: Songs of Stevie Wonder and The Jazz Side Of The Moon by musical artists Seamus Blake, Ari Hoenig, Mike Moreno, and Sam Yahel.  Both titles are from the Chesky Recrods label and are priced at $26.98.

FUN

DIY Chocolate Records

Meet a man who makes sweet sweet music... A video showing the creation of a chocolate record that actually plays yummy music.

DIY Audio, Hi-Fi and Music Roundup #1

Welcome to our first DIY Audio, Hi-Fi and Music Roundup.  The DIY Audio, Hi-Fi and Music Roundup will be a sort of newsletter that will contain news, updates and various bits (ie. mostly weblinks) on the topic of DIY Audio, Hi-Fi Audio and Music.  We will try produce a DIY Audio, Hi-Fi and Music Roundup every few months.  As always we appreciate your feedback, comments and suggestions or if you have any news tips, send us an email and let us know.  Our email address is noted in the site banner at the top of the page.

PROJECTS

Oatley Electronics K282 RIAA Phono Preamp Kit
Mark Houston (Australia) built and reviewed the Oatley Electronics K282 RIAA Phono Preamp Kit for moving magnet (MM) cartridges.  The RIAA phono preamp kit is inexpensive, simple to put together and ideal for those new to tubes as it does not use a high voltage supply.  For more information see Mark's build and review of the 6418 Tube (Valve) RIAA Phono Preamplifier Kit.

Oatley Electronics K282 RIAA Phono Preamp Kit

NP-100v12: 12AU7 (ECC82) / IRF510 Headphone Amp

Rogers Gomez (USA) has put together a detailed update for his popular low voltage tube and MOSFET hybrid headphone amplifier project from 2008.  The updated project instructions include PCB image files and a detailed BOM.  The instructions are quite thorough and as this tube project uses a low voltage supply it is also well suited for those who are new to tubes.  Full details for the headphone amplifier are available on the NP-100v12: 12AU7 (ECC82) / IRF510 Headphone Amp project page.  I use a very similar class-A circuit to drive a pair of Grado SR80 headphones and the combination is very nice.

NP-100v12: 12AU7 (ECC82) Tube / IRF510 MOSFET Headphone Amp

PARTS AND KITS

Oatley Electronics K281 Tube/Chip Hybrid Amplifier
The good folks at Oatley Electronics have released a new tube / opamp hybrid amplifier kit.  The kit is based around the 6418 sub-miniature pentode valves and a National Semiconductor LM1875 operational amplifier.  Like the other Oatley audio kits we have tried out this one is also no frills and relatively inexpensive (about $30) per mono kit quite inexpensive.  The small amplifier kit will deliver about 5W into an 8 Ohm load or 10W into a 4 Ohm load.  The kit includes a suitable power adapter (110-240VAC to 24VDC @ 1A) and all on-board parts including a heat sink.  The kit can be purchased from Oatley Electronics: K281 – Tube Based 5/10W Power Amplifier Kit.  Mark has already put one of the K281 kits together and you can read his build and comments about the kit on the forum: Oatley Electronics K281 tube/chip hybrid power amp. 

Oatley Electronics K281 Tube/Chip Hybrid Amplifier

MooseFET Line Preamplifier PCB

The MooseFET Line Preamplifier PCBs from Classic Valve Design are now available for $14.50US each.  From the Classic Valve Design website:

Our MOSFET line stage sonically resembles a single ended triode design with similar FFT frequency spectra due to the special design. A great way to have a "tubey" sound with the convenience of solid state.

Full details (including a schematic) are available for the MooseFET line stage and the boads can be purchased from Classic Valve Design: MooseFET PCB.  There is also some additional MooseFET information on the MooseFET Preamplifier thread on the forum. 

MooseFET PCB from Classic Valve Design

Hammond Aluminum Chassis with Walnut Sides
I was on the Hammond Manufacturing website sizing up some chassis today and I noticed that they have a new line of steel and aluminum enclosures with walnut sides.  The new chassis are called: Walnut Chassis with Aluminum Panels (HWCHAS Series); Steel Chassis with Walnut Side Panels (1441 CWW & 1431 Series) and Aluminum Chassis with Walnut Side Panels (1444 CWW & 1434 Series).  From the photos on the Hammond website the chassis look very nice.  We will be ordering a few of the Aluminum Chassis with Walnut Side Panels and we will let you know how they turn out.

Hammond Aluminum Chassis with Walnut Sides

Bourns Multi-Turn Potentiometers 
Lately I've been almost exclusively using Bourns multi-turn potentiometers instead of the cheap trimmer types.  Anurag Chugh took apart a Bourns 3296 Potentiometer and gives us an inside look at the construction of the pot.

Bourns 3296 Multi-turn Potentiometer Internals

NEWS

Over the weekend we caught wind of a new online hi-fi publication called Hifi Zine - The independent audio webzine.  Their June issue is online and it is quite impressive with plenty of good reading material including a couple of articles on our favorite topic, DIY tube amplifiers.

FUN

Vintage and Retro Hi-Fi
We know you like Hi-Fi Audio and if you are also interested in retro hi-fi, check out the retro vintage modern hi-fi blog for some great retro photos.  The photo below (source: hifilit.com) is part of a retro Karlson Speaker Enclosures advertisement.  The Karlson speaker sure looks like a fine wedding gift to me. 

Retro Karlson Speaker Advertisement

Vacuum Tube Art
We are big tube fans here and when I saw these vacuum tube sculptures (via The Blue Tube Project) we just had to share them with our readers.  The artwork is from Sageous Galleries - Vacuum Tube Sculptures, Literature and Oils.  Probably not surprising to some, I think a vacuum tube sculpture would also make a fine wedding gift!

Vacuum Tube Sculpture