K&K Audio has moved!

Over the past month both K&K Audio and my family have moved 18 miles northwest to an unincorporated part of Chapel Hill. It’s quieter here and the pace is more relaxed. It’s been a painful physical transition due to the stuff (mostly audio related) I had accumulated over 27 years at the prior address. I have only had my audio listening system up for five days now after nearly 4 weeks. I have been pleasantly surprised that the new listening room, which is only about 5-10% bigger than its predecessor, is more to my sonic taste than the one I’ve used since 1995.

I am sorry that the telephone number has changed (unavoidable, because it’s a landline), but the new contact info will be posted on the website at the same time as this update. I look forward to talking to you in the future! The next rendition of the Maxxed-Out Phono Preamp is on my list of projects, as is a higher current version of the 300-600V shunt regulator. I am just as impatient as anyone to get these products tested and fully developed…

New Lundahl MC Step-Up Transformer

Lundahl has developed a new moving coil step-up transformer that meets a need present in both the tube and solid state phono preamp worlds.  That need is created when the phono preamp has more gain than is necessary for the usual MM cartridge levels ( 5mV), but not enough gain to interface well with an MC cartridge that has an output level of 0.2-0.5mV.  If your phono preamp has a gain at 1KHz in the neighborhood of 50-58dB you are in that range where you need to use the preamp volume control at a higher than normal setting to get the music level up to “normal” levels with a low to medium output MC cartridge.  This results in poorer noise performance and audible loss of dynamic contrast.  With the LL1963 you can step the signal level from the cartridge up by 10dB or 16dB to overcome this problem.

I recently had an e-mail conversation with a music listener who tried a pair of LL1963s between his MC cartridge and a high end tube phono preamp with 58dB of gain and he wrote after hearing it in his system, “It’s not that often when you encounter something that is a game changer and affordable.”  He had borrowed his buddy’s step-ups to audition and following the audition purchased a pair and the corresponding PC board for himself so he could install the transformers into his phono preamp chassis.  They are also available in the format of the Premium MC Phono Step-Up, kit or assembled so they can be installed without soldering.

Price Increases on “Other Kits”

After much deliberation I have made relatively minor increases in the prices of the support kits that I have offered since the beginning of K&K Audio in 2003. The price for the earliest of these, the Basic Current Source Kit, has never been changed! Transformer prices will remain as they are for at least 7 more months.

New Lundahl Audiophile Transformer and PS Chokes

Lundahl Transformers will shortly announce the availability and pricing for three new parts.  The data sheets are linked below:

LL2766 – a compact (LL1660 size) low power output transformer for tube amplifiers, SE or PP.  Think SE 45/46/47 or PP 6V6GT and many more low power possibilities…

LL2771 – a big (1A, 3H) power supply choke.  Would have been great for my PSE6C33C amp power supply….

LL2772 – a low resistance filament current choke (3A, 80mH).  Perfect for the Russian GM-70, for example.

Gerus Audio is using Lundahl Transformers in their Amplifiers

Scott Gerus has been building tube amplifiers for some time now, but recently retired and has created a website (www.300Bamps.com) to make his designs more broadly available.  He has designed and built several monoblock and stereo single-ended and push-pull amplifiers, which can be viewed on his website.  Interestingly, he does the woodworking and metalworking for his products himself!  Have a look.  These aren’t simple aluminum boxes with tubes and transformers parked on the top!  (like I build for myself…)

After using Lundahl output transformers in a few amplifiers over the past two years, he recently posted on his website:

“Over the years I’ve used Hammond, Electra-Print, Transcendar and Pliton OPT’s.  The only one that comes close to the Lundahl is Plitron, and they cost twice as much and take up 3 times the space!

You can’t beat the Lundahl’s for the Price!”   We agree, Scott!

Erhard Audio uses Lundahl Output Transformers in their designs

We are happy to note that Erhard Audio (formerly Tube Nirvana) has auditioned Lundahl amplifier output transformers in their models and, as a result, are using Lundahl output transformers now in production.  You can read their take on these and other parts decisions here:  www.erhard-audio.com/Blog.html and see power the amplifiers here:

www.erhard-audio.com/Ray.html

www.erhard-audio.com/Elvis.html

www.erhard-audio.com/Buddy.html

and a headphone amplifier:

www.erhard-audio.com/Billie.html

And while you’re at it, look at the chassis artistry, as well!

New Lundahl Catalog Available

Lundahl Transformers has compiled a new catalog in .pdf format that is downloadable from their website.  It includes data sheets for the newest models, as well as the older ones that we have relied on for great sound over twenty years.  It can be viewed or downloaded here:  http://www.lundahl.se/technical-information/

Fall Inventory Reduction Sale on Raleigh Audio Products

Dave Davenport of Raleigh Audio has announced a Fall inventory-reduction sale. While inventory lasts, assembled DACs and Preamps are being offered at a 20% discount.

As is usual, the Preamps are a fixed configuration, while the input configuration of the DACs are custom. Below are listed some sample configurations with their sales prices. You can order those configurations for the prices shown or ask for a quote for a custom configuration. Use the sample configurations for a ballpark idea of where the price of a custom configuration might come in.

In addition, there is one unit that was built to prove the documentation and provide pictures for the website. This is a fully configured Standard “DAC #4” configuration and is offered at a 30% discount – an additional savings of $300. Because this unit is already built, the input configuration cannot be customized.

Further details for these DACs and Preamps can be seen under the “Products” menu on this site.  Please ask if you have questions.  Don’t miss this opportunity to own a custom configured Raleigh Audio product at a great price!

 

Item Sales Price
DAC #1 (Standard)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR)
$2199
DAC #2 (Standard)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), I2S
$2299
DAC #3 (Standard)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), USB
$2499
DAC #4 (Standard)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), I2S, USB
$2699
Special – one only
DAC #4 (Standard)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), I2S, USB
$2399
DAC #5 (Premium)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR)
$3199
DAC #6 (Premium)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), I2S
$3299
DAC #7 (Premium)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), USB
$3499
DAC #8 (Premium)
SPDIF (RCA), SPDIF (BNC), AES/EBU (XLR), I2S, USB
$3699
Preamp #1 (Standard)
four (single-ended RCA), two (balanced XLR)
$2079
Preamp #2 (Premium)four (single-ended RCA), two (balanced XLR) $2879

Monoblock PP Amplifier Using New Amplifier Kits

I’ve designed and begun the assembly of a PP KT120/150 monoblock amplifier that uses the new capacitor-coupled 6J49P PP input stage and one of the new power supply kits.  The power supply is choke input for low noise and uses a lower cost, over-sized toroidal power transformer.  The output stage is operated Class A1 with a common current source in the cathode circuit (on the heat sink at the back of the chassis) and can be switched between triode and “ultralinear” operation.  The chassis (20″ x 10″ x 3.2″) is made from Par-Metal Products 10 series sides and backs, with an aluminum top panel (0.09 inches thick) drilled by me and powder coated locally in “satin black”.

PP monoblock assembly

PP monoblock assembly

As you can (barely) see in the schematic below, there are relatively few components off of the PC boards, making wiring a straightforward task.  I’ll post more info as the build continues.

Capacitor-Coupled 2 Stage PP Class A1 Amplifier

Schematic