There are many companies making dedicated headphones amps, and many that sell headphones. Meet John Grado of family-owned Grado Labs. He would like to cover both bases for you, and we like what we hear. John is the nephew of Joseph Grado, credited with the invention of the stereo moving coil cartridge, who founded the company way back in 1953. All Grado cartridges and headphones are hand made in the New York factory; including the carved mahogany reference series headphones that John has developed. The RS1 and its baby brother the RS2 sit between the range topping GS1000 Statement series and the less expensive Prestige series headphones.
Common to all Grado headphones is an open back design featuring a vented diaphragm with a large air chamber for extended bass response. The diaphragm is made from a low mass polymer mated to the compliance of the suspension to optimize the low frequency resonance. The voice coils are wound from ultra-pure, long crystal oxygen-free copper, which is also used in the seven foot connecting cable. Very high power neodymium magnets are used for high efficiency. As a bonus the RS1 comes with a high quality 15 foot extension cable and a converter for connection to an iPod. It's also nice to know that the ear cushions are user-replaceable.
The RS1 is efficient enough to mate well with an iPod, but for the best sound you should use a headphone amp, such as the companion Grado RA1. This small wooden box is powered by two 9v batteries, good for up to 40 hours of listening. Grado also offers an AC powered version. For those headphones with higher impedance and lower sensitivity, a high gain version, the RA1-HG fits the bill. We used the battery-powered version for our test, alongside the reference Graham Sleek Solo (US $950).
The specs reveal a very wide bandwidth device, response extending from 12 Hz to 30 KHz with very tight driver matching, while the low weight of 9 ounces contribute to user comfort. I find the Grados much more comfortable than the vice-like grip of the Sennheiser HD 650.
Synergy is always a key to getting the best performance, and there is a lesson to be learned here. The RA1 and RS1 are made for each other, and even though the inexpensive RA1 is not in the same class as the Graham Sleek Solo, it provides the better mate for the RS1. It doesn't reach quite the same level of definition in bass or match the speed of response of the Solo, but it does provide realistic image size. The Solo spreads the image so wide with the RS1 as to leave something of a hole in the middle, despite pairing very well with some other fine 'phones. So for our testing we will compare the RA1/RS1 combination to the Solo/AKG.
The Grado combination is punchy and warm, bringing you close to the music even at relatively low listening levels. There is a lot of kick in the bass and warmth in the midband, which will suit cool digital sources a lot better than some more analytical 'phones like Stax electrostatics.
The Grados work very well together, presenting a realistic sound stage with strong dynamics and as much volume as you should safely consume. Grand opera comes through with real presence and the full weight and beauty of the voices is there to enjoy. Give it some aggressive music, like Benny Green's jazz trio and you get visceral excitement, really strong bass and all enveloping swing. With the AKG K1000/Solo pairing music is much more clearly defined up top, smoother and more pleasant, but you don't get the full force of the bass energy and without that the music loses its passion.
It soon becomes clear that the Grados act like a magnifying glass to the recording. Give them a top quality disc and you get magnificent, detailed and full-bodied music, totally captivating. It's like sitting in the front row. Feed it with less than perfect material and you see all the flaws in living color. This is not a forgiving combination.
Instrumental or vocal, electric or acoustic, is very satisfying through the Grados. The image is stable and well located, giving a convincing image size. Haydn's quartets emerge particularly well on these 'phones, perhaps because the mahogany frames preserve the rich sound of the wooden instruments. When the cello grunts you feel it, and when the violin soars, rich harmonics abound. When it comes to the vocals, there's meat on the bones, while the AKG K1000 can sometimes sound quite lean and miss the artist's passion.
The RA1 offers excellent value for money, and does a fine job powering phones from Sennheiser, Shure and Ultimate Ears. It does especially well with Grado 'phones and does not embarrass itself next to state of the art components. The RS1 is at its best with instrumental, vocal and small-scale groups, particularly if you like your music up front and personal. The Grados are clearly a music lover's component, trading a little accuracy and detail for warmth, presence and tonal color a trade most tube lovers would make any day. Try them on for comfort and sound, you'll not be disappointed.