Manley Labs Oasis Phono Preamp

The Manley Oasis Phono Stage officially replaces the Manley Chinook Phono. The Oasis Phono Preamplifier provides a quieter, blacker background and yields quicker hifi sonic extremes compared to older linear PSU designs. EveAnna Manley, the president, recalls the moment she first made the comparison. She brought a regular Chinook with its linear power supply, a stock unit, to Los Angeles to listen to it against a second Chinook modified to work with the new MANLEY POWER® switch mode power supply. At Pete Lyman's Infrasonic Mastering studio, they conducted a precise comparative listening test between the two units using vinyl records that Lyman had cut the masters for on his lathe. Even though they could not see which unit they were listening to, the sonic differences were unmistakable, and both heard the same superiority in the new power supply design. Manley expressed amazement at the stunning technical and sonic accomplishment MANLEY POWER represents and delivers as more designs are adapted to take advantage of the proprietary system. The Oasis Phono Stage offers improved convenience over the older Chinook, as the gain selections have been moved from inside the chassis to the rear panel for easier access, residing next to the resistive and capacitive loading DIP switches. There are numerous loading options to mate with any Moving Coil or Moving Magnet cartridge. Once the gain and Loading are set for the cartridge, no further adjustments are needed. The Oasis features an upgraded, more luxurious high-end chassis design, while its efficient internal build keeps the price affordable. Like all Manley products, each Oasis Phono Stage is handcrafted in the USA by American workers at Manley Lab's Southern Californian factory located just 35 miles east of Los Angeles. Recommended Dragon Cable: We recommend pairing the Manley Lab's Oasis Phono Stage with the Silver Dragon Interconnect. Sold in Pairs, the Silver Dragon V2 is our top-of-the-line silver conductor-based interconnect. With a braided geometry and amazing shielding, this interconnect is a remarkable solution where noise isolation is key. The Silver Dragon is the original cable. Silver strands clarify instrument separation, increase soundstage, and find previously lost high and mid-frequency sounds. Transients appear more cohesive and the bass is tighter for a more controlled sound. DRIVEN BY MANLEY POWER® "The logical successor to the legacy Chinook, our new OASIS Phono Stage deploys our modern dedicated power supply and construction to usher a new series of Manley preamplifier designs to your home. Named after one of our dearest Mastering Studio partners, the OASIS carries forth the clean and precise audio circuits of the prior Manley Steelhead and Chinook audio paths into a new age of high fidelity preamplification offerings from Manley Labs." -Manley Labs Each channel of the Oasis Phono Stage employs the two triode sections of a 6922 tube for amplification, assisted by low-noise FETs that receive the signal below each cathode. The decoding task to restore the originally intended frequency response to the audio signal is performed by highly accurate passive RIAA equalization networks. In the Oasis, the signal does not pass through any integrated circuits (ICs). However, ICs are used in a servo configuration to apply a precise biasing voltage to the gate of each FET. Other chips perform logic functions to control the turn-on and shut-down sequences, activating the mute relays to prevent unwanted bumps or noises when the unit is power cycling. Importantly, the signal is directly coupled from the gain stages to another 6922 dual triode, which serves as the output driver in a White Follower configuration. This output stage circuit is preferred due to its super-low output impedance and robust current-driving capabilities. It can easily drive long cable lengths and challenging loads, whether tube or solid-state. The Manley Laboratories Oasis Phono Stage features a new chassis design shared with three upcoming Manley preamplifiers. The powder-coated, zinc-passivated steel housing has a luxurious appearance with smooth, rounded edges on the substantial top cover. The front face is adorned with a 3/8" thick CNC-milled faceplate featuring an inlaid "racetrack" insert for visual interest. The OASIS moniker is laser-engraved on the façade. Faceplates are available in traditional "Manley Blue" (also known as "Pewter Grey"), Silver, or Black. Setting up the Oasis is straightforward, with all necessary switches located on the rear panel for optimizing the cartridge interface. GAIN can be set to 45dB, 50dB, 60dB, or 65dB, accommodating all Moving-Magnet and Moving-Coil cartridges. DIP switches adjust input resistive and capacitance loading values, offering 31 options between 26 and 800 Ohms plus 47k Ohms, and 7 capacitive loading choices between 50 pF and 350 pF. Audiophile-grade components are used throughout, embodying Manley's dedication to seductive sonics and reliability. At about a quarter of the price of the Steelhead preamplifier, the Oasis maintains a focus on elegant design, careful execution, efficient construction, and appreciable quality. F.A.Q Q: How is the OASIS different from the CHINOOK? The new chassis is deeper and has a solid steel top with big rounded radiused side edges which will be welcomed as a big improvement over the more primitive CHINOOK chassis.  The faceplate design features an elegant inlaid "racetrack" in contrasting color to the mother plate for visual interest. Facias will be available in black and blue or blue and black. Probably silver and black also...  The gain switches are relocated to the rear panel next to the loading switches for easier access.  The Oasis is powered by MANLEY POWER®, Manley's new SMPS. It's a big sonic improvement. Q: I want to use another external step-up transformer. Can I run it into my OASIS with the load set for 47 kOhms? A: Yes, you can run an external MC step-up transformer and run that into the OASIS input. Set the load for 47 kOhms and then set the GAIN to the lower setting. Q: I have an XYZ Model Blah Blah cartridge. Where do I set the loads? Is it an MM or an MC cartridge? Where do I set the gain? A: Gain is gain. It doesn't care whether it is an MC or MM cartridge or an external step-up transformer. Usually, MM cartridges are going to be on the lower gain settings, like around 40dB of gain in a phono stage, and MCs on the higher gain settings, around 60dB of gain or so. Usually, you'll see MM cartridges with a typical output of 1 milliVolt. MC cartridges typically have about 0.5 milliVolts, for example. You'll have to see how much gain you need in your system and set the gain for as little as you can get away with. If you have cranked your preamplifier's Volume Control all the way up and you still can't play loud enough, then switch the gain up on your phono stage. What you don't want is max gain (and max noise) in your phono stage and then your line stage's Volume Control is barely cracked open at 9 o'clock. Loading also doesn't care where you set the gain. You can set the loading for any cartridge or external step-up transformer wherever you want to. You will never harm anything or blow anything up. The loading resistor helps dampen high-frequency resonances of cartridges (and other inductors). Adding capacitance to low-impedance cartridges will have no audible effect. Most MM cartridges are going to require a standard 47 kOhms resistive load setting with some capacitance added in parallel with the resistor. You would ultimately also want to add the cable capacitance in your calculations. Read your Manley OASIS Owner’s Manual as there is lots of info about this topic in your manual. Always refer to your cartridge manufacturer's website or owner's manual for the suggested load and then set your Manley phono stage to that load setting or as close to it as possible. "DC Resistance" and "Internal Impedance" refer to the measurement of the winding inside the cartridge and that is NOT what the recommended load setting is. If it is not clear on the cartridge maker's website or owner's manual what the Recommended Load for their cartridge is, please contact the cartridge manufacturer and have them clarify what the recommended load for their cartridge is. Being exactly on the number they suggest or being a few Ohms different is not going to make or break anything. All of these load settings have a very very subtle effect and they are difficult to hear sometimes. Q: Which of the vacuum tubes are the input tubes? A: The input tubes are located towards the back of the chassis in this unit. You can follow the wiring from the INPUT RCA jacks straight to the INPUT tubes. The output tubes are closest to the big giant white output capacitors and you can follow the OUTPUT cabling from those capacitors to the OUTPUT RCA jacks. Q: I think I need more gain. What do I do? The gain is adjusted by changing the resistors at the source of each FET in the first two gain stages. You can address these DIP switches on the rear panel of the unit and follow along the markings there. Generally speaking, most Moving-Magnet cartridges will use the 45dB or 50dB gain settings, and most Moving Coil pickups will prefer the higher 60dB and 65dB gain settings. However, it is always suggested to start with the lower gain choices of the two first to make sure you don't really need anything additional. If your preamp's volume control is out of range and you still can't get enough level out of your whole system, then you need more gain. With more gain comes more noise, so start with the stock settings before pre-judging that you need extra gain. Most folks do not need more gain. More is not necessarily better. Q What are those LEDs inside the unit? I can see them when I look into the top cover. A: Manley has installed LEDs that will light up on the PCB to indicate the status of the gain selected. The LEDs are located towards the front left side of the main PCB and are labeled: 45dB Green LED +15dB Red LED + 5dB Red LED The Oasis starts with 45dB of gain as standard and is always active. The Green LED should always be lit. On the rear panel of the chassis, pushing DIP switches down on this Oasis unit engages the switch. The selected gain amount adds to the stock base 45dB level. 45dB = Both gain DIP switches up = the green led (always on) 50dB = +15dB DIP Switch up; +5dB DIP switch down = green LED + the red LED indicating +5dB selection, because 45 + 5 = 50. 60dB = +15dB DIP Switch down; +5dB DIP switch up = green LED + the red LED indicating +15dB selection, because 45 + 15 = 60. 65dB = +15dB DIP Switch down; +5dB DIP switch down = green + the red LED indicating +15dB selection + the red LED indicating +5dB selection, because 45 + 5 + 15 = 65. Q: I am looking at a bit of tube rolling on my Chinook phono stage. I am considering replacing the tubes with Voskhod 6N1P-EB. These have the same specs as 6DJ8 except the filament is double at 600ma. Is it safe to replace the 6922 tubes with these tubes?? A: Yes, with this unit running from the MANLEY POWER® SMPS power supply, there should be ample current available in the heater rail to accommodate the Voskhod 6N1P-EB tubes. Q: How do I reconfigure the mains voltage when I move to another country? A: You do not have to! The OASIS Phono Stage uses Manley's fantastic modern MANLEY POWER switch mode power supply which operates all over the world at any voltage between 95VAC to 254VAC and at 50Hz or 60Hz. Q: Can I update my Manley CHINOOK to an OASIS? A: No.