Signal Path / Decco / Peachtree


Today we have the pleasure of testing two products from Signal Path Technology International. First their Era Design-4 loudspeakers. Second is the Decco hybrid integrated amplifier. Originally Signal Path International began as a distributor/importer for the highly respected Musical Fidelity line of HiFi products. Several years down the road the company decided to manufacture their own products and began by launching their Era loudspeaker line. The line-up was an immediate success, garnering rave reviews from Stereophile; Era Acoustics Design-4 loudspeaker & SUB10 subwoofer and others. We are fortunate to have Signal Path send along a pair of the Design-4's to mate with their latest product and the focal point of this review, their Decco integrated amp for home PC-Audio.



Decco is the brainchild of Signal Path International executives, David Solomon, Jim Spainhour, David Richardson and was designed by Scott Nixon. The project was inspired in large part by David Solomon whom took note of two interrelated phenomena. The burgeoning number of music files which coincide with a drop in music CD sales and the longtime absence of High End Audio for PC-audio. Increasingly he saw the need for a digital converter designed for music files and a device capable of realistic playback.

To these ends Signal Path founded Peachtree Audio with the express purpose to design and manufacture a product to fulfill the desired above. The result is Decco a hybrid, integrated amplifier sporting a USB fed DAC among other digital connects. As soon as Decco was demonstrated at various 2007 trade shows including CEDIA 2007 and RMAF 2007 the Stereophile Blog was buzzing. Decco elevates your PC Audio far beyond the very best manufacturers for that market have to offer, in addition it gives Audiophiles a reprieve whom burn a music CD/DVD then run to their Listening Room to hear their compilation. Today a 1-terabyte hard drive can be found for as low as $125 effectively transforming any PC into a Music Server. In a recent review with Consumer Electronics Daily News Peachtree Audio's David Solomon made the following comments on the inspiration, benefits and intended target for Decco;

Two years ago, much aware of consumers’ rising interest in computer audio and in peripheral products like Sonos, Apple TV and slim devices, we recognized a need for products that would significantly upgrade their audio performance...We know of no other electronics manufacturer who offers an integrated amplifier as elegantly designed as the Peachtree Audio Decco. When our dealers heard we were offering a state-of-the-art 50wpc integrated amp with two internal DACs at $799, they were incredulous. But when they actually heard the product and saw the whole package in an elegant cabinet, they were blown away. The real kicker is when we simply hook the Decco to a computer through the USB input....Peachtree Audio’s target customer is anyone who downloads music and uses a computer as an audio source. Right now that’s more than 150 million people. If only five percent of them decide to upgrade their computer audio system in the next couple years, we’ll see a massive revolution in hifi.

Peachtree fruit has left a bittersweet taste on some audiophile palettes who can't imagine how the cost can be kept so low. Peachtree looked to the DIY Audio community to settle on a design and while other High End manufacturers have had success with this method, not so many have done what Peachtree has. The end product pays homage to the Grass Roots community by keeping costs within reach of those very same hobbyists. The basis for Decco's is was achieved by utilizing what is known commonly around the DIY Audiophile watering-hole as Chip-amp or Gain clone designs. Mentioned above Scott Nixon is well respected for his tube based DACs and to a lesser extent his Chip-amps. I'll delve into the chip-amp phenomenon in the next section.

Decco Specifications:
• 3 digital inputs: USB/Toslink/SPDIF digital inputs
• Decodes mp3, mp4, flac, AFF, wav, plus all others
• Tube pre-amp section
• 50 watt per channel high current A/B amplifier
• 2 analog inputs
• +5dB, 55Hz bass EQ for small speakers
• Detachable power cord
• Multi voltage switchable toridal power transformer
• Preamp Stereo output fro additional amplifier or subwoofer
• Remote control
• Slot in back to hide Sonos ZP80
• 15"W x 5"H x 14"D 22lbs out of box, 24 lbs in box

Thumbnails below indicate Decco arrived in perfect shape, shipping with the driver tube in place. Double boxed with the internal boxed braced in foam and within this box the amplifier is bubble wrapped, very secure. In the right photo note Signalpath nestled the remote and an additional pre-amp driver stage tube. Employing a valve in the op-amp is not a rare design occurrence, but given Decco's affordability its indicative of they've placed sound quality first.



The face-plate on Decco is solid aluminum, almost a 1/4" thick with a glass window for the aforementioned Russian Rocket Logo 6H23N (6922 family) driver tube, ergonomically clean. The large attenuator on the right side is motorized and many Decco's left the factory with Alps motorized potentiometers which is not to say its replacement is inferior. Just beneath the remote/manual operated volume control is a quality headphone jack. In addition manual adjustment d by remote including the On/Off-Standby power button, USB (most pertinent for this review), COAX, OPT, AUX 1 and AUX 2.



On the rear of the amplifier from left to right, AC input with voltage selector, four Acrylic encased 5-way binding posts, inputs/outputs, which also include a Bass EQ button which Peachtree literature describes as a "+5dB, 55Hz bass EQ for small speakers." I didn't find a need for this and any type of EQ is usually foreboding since its defeatist for so many reasons in Audiophile philosophy 101, but I did test it which I'll discuss in the Listening section.



In the close-up below, once again we see left and right channel, acrylic encased copper five-way binding posts and pre-amp outs. The latter gives you the ability to use Decco as both a simple pre-amp and digital pre-amp. In fact in upcoming tests I'll use the Decco as a pre-amp with both solid state and vacuum tube amps. Decco's tube driver stage should augment a solid state amp which may seem a bit bright. Further connectors include AUX-1 & AUX-2 RCA inputs, and the all important (for PC owners) digital inputs including USB, OPT, COAX. Finally the Bass EQ button, a blasphemous appendage any self respecting Enthusiast wouldn't dare touch.



The number of digital options and its internal DAC not only impart Decco with versatility, the Phillips DAC in combination with a vacuum tube driven pre-amp Decco's designers intended to infuse a balance in the sound. Hybrid amplifiers traditionally haven't been all that successful, however; chip-amp designs seem to benefit from the combination. Below Decco's rear view with all connections in place. Cables shown are Zu Audio Julian speaker cables, which produced a great sound, however; their price-tag must be considered at $335.



Found in the thumbnail below the remote provided with Decco is pretty straightforward, everything you can do on the front panel manually can be done with the remote. Traditionally remote controls were of little interest since many thought a motorized attenuator found on Audiophile grade hardware since there were few high quality motorized potentiometers. Early on Audiophiles were left with the choice of placing amplifier between the speakers (usually on the floor so as not to distort imaging) shortening speaker cable lengths. To keep source controls close at hand interconnects were required anywhere from 8ft ~ 12ft, a costly investment.

This also aided in removing source components from lower base speaker resonations. Often systems are placed on multi-level racks placed between the speakers. If flush with the speakers the rack will distort imaging, especially if it is of equal height with the drivers. In this review I will be using the Decco amplifier's USB DAC and placing the amplifier on the Thermaltake MozartTx. This PC cube tower case is 28" in height but only 14" deep and 13" wide. The Mozart Tx was designed with such unique applications in mind and because of its conservative depth and added height compared to most PC-tower cases it was easy to push the case back and speakers forward so as not to degrade imaging.



Onto the design concept behind Decco...