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Melos SHA-1 headphone amplifier Page 2
Still with me? An additional 6µF film cap per channel, the metal-can Frenchies I described earlier, is in series with the line-level output, which is simply paralleled with the headphone jack but muted whenever the headphones are plugged in. George Bischoff explains that the SHA-1 is designed to have an output impedance of 8 ohms with plenty of current drive for the 40 ohm Grado headphones when used as a headphone amp, but the line-stage configuration sports an output impedance of a half an ohm coupled with very little current drive, as most power amplifiers have high input impedances which don't present a difficult load. The Melos SHA-1 can handle two line-level sources plugged into its rear, and sports two headphone jacks on the front panel. There is no balance control, and the revolution will not be televised.
Footnote 4: For readers over 60, that's Iggy, Ron, and Scott, not Larry, Moe, and Curly. Look for "Building A Library: Iggy Pop & The Stooges" in an upcoming Stereophile, wherever fine books are sold.—Corey Greenberg
Universal system
The Melos headphone amplifier is also a line-level preamp, so it saw a lot of use as a preamp as well as driving my Grado HP-2s. Replacing my own buffered passive preamp, the SHA-1 was auditioned with an analog setup of the Well-Tempered Record Player fitted with Sumiko's Arm Wrap and Blue Point Special cartridge and the phono stage of an Audio Research SP-14, hot-rodded via the rec-out jacks to one of the Melos's two line-level inputs. CDs were played with the Theta Data/DS Pro Basic II combo. Kables were mostly Kimber, KCAG interconnect and 4AG speaker, with a piece of AudioQuest Lapis between the Well-Tempered and the SP-14. Amps included the VTL Deluxe 225s, as well as the Forté Model 4 and Muse Model One Hundred. Speakers were mainly ProAc Response Twos mated with the mighty Muse Model 18 subwoofer, but I also spent some time listening to two ribbon/dynamic hybrids: Eminent Technology LFT-VIIIs and Apogee Centaur Minors. All gear was plugged into Power Wedge AC line conditioners.
I've just finished playing around with a gaggle of RoomTunes Michael Green sent me, and while I can't say I feel they transport me into another dimension, they do make an obvious and significant improvement to the sound of my listening room. I have some additional observations about these RoomTunes, so look for a "Follow-Up" PDQ.
As the Melos is basically an ALPS "Black Beauty" volume control followed by a tube/FET output circuit, I thought it would be interesting to compare it to the sound of the same pot followed only by a pair of BUF-03 high-quality buffers—ie, Aunt Corey's Homemade Buffered Passive Preamp—so I replaced the Penny & Giles pot I normally use in the unit with the ALPS "Black Beauty" I bought last year from Joe Grado to see just how close to the BUF-03's neutrality the Melos's circuit could approach.
Elvis couldn't stand Donovan, so there'll be no anecdote about the King this month. Instead, you get to learn that my lovely sister Jennifer was named for Donovan's "Jennifer Juniper." And don't eat the brown acid.
Sunshine superpreamp
My usual practice when getting new gear for review is to first drop it into my bedroom system. This second system comprises equipment that's either waiting its turn for review or stuff I like to keep on hand as alternate references. In addition to speeding up the time it takes to break-in new gear, I also get to blast the Stooges (footnote 4) while I shower in the morning without subjecting the foo-foo gear in the main listening room to undue stress.
The preamp in this bedroom system is a passive unit I built a few years back after reading my man Ben Duncan's DIY article in Vol.11 No.2—just a stereo 10k Bourns volume control and some RCA jacks in a li'l black box. But I'd been having some trouble driving the just-arrived Eminent Technology LFT-VIII speakers with this preamp in the chain, the somewhat inefficient ETs requiring more gain to give up the goods than my passive could push. And the newly arrived Melos SHA-1 needed some break-in, too...
So I killed two audiophiles with one drive-by and replaced the passive preamp with the Melos headphone amp. I slapped Stevie Ray Vaughan's The Sky Is Crying CD into the JVC XL-Z1050, set it for repeat, and started to walk out of the room.
"What the—?!"
The sound was startlingly good. And the Melos was right out of the box. I sat back down on my bed and ended up listening to the whole CD. Twice. Driven by the Muse Model 100 amplifier with 10' lengths of AudioQuest's Type 4 $2/ft. speaker cable, the system sounded clean, focused, and more fleshed-out than ever before.
Footnote 4: For readers over 60, that's Iggy, Ron, and Scott, not Larry, Moe, and Curly. Look for "Building A Library: Iggy Pop & The Stooges" in an upcoming Stereophile, wherever fine books are sold.—Corey Greenberg
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