Amp recommended?
Nov 6, 2002 at 7:08 AM Post #2 of 10
The RA-1 is known to be a rip off. You could build it yourself for $20. That said, it's not a very good amp. You can do much better for $250. Anyway, at that price range, you're on the border between an all-out portable amp and a pretty basic home amp.

So the question is? Do you want/need portability?

If not, my recommendations would either be a wall-powered META42, or you buy a Corda HA-1 kit for $25 more than your budget and assemble it. If you want portability, also look for a battery powered META42 or a Porta Corda II.
 
Nov 6, 2002 at 7:06 PM Post #4 of 10
As long as you get a regulated/linear power supply, there should be no hum from the power source. Kevin Gilmore's power supply is actually quieter than most batteries.
 
Nov 6, 2002 at 7:46 PM Post #5 of 10
Quote:

Originally posted by antness
The RA-1 is known to be a rip off. You could build it yourself for $20. That said, it's not a very good amp.


If you don't like the RA-1, say so, but your opinion is just that, and it is not universally held. Personally, I rate the RA-1 in the same league as the Corda HA-1 (I've heard the Corda several times now, and it's a very nice amp). Those two, together with the X-Can v2, are the commercial amps that I've heard and would recommend in that price range. The Creek OBH-11se tends to get overlooked, and is a nice amp also, but I thought the sound tended to be on the cold and analytical side of neutral. With Grado headphones, I'd give the edge to the RA-1. I haven't heard the DIY amps, and can't comment on them.
 
Nov 6, 2002 at 8:50 PM Post #6 of 10
I humbly disagree. I owned an RA-1 and it has close to zero bass impact, even with Grados. Also, the highs were very bright, almost to the point of harshness. People will say that it's my sources, but I know my sources fairly well, and the RA-1 was just poor with all of them. Perhaps if you own a source with a hefty output stage and are just using the RA-1 as a buffer, then things would sound good. I know Hirsch is an ART DI/O fan, and those units do have fairly hefty output stages. The RA-1 doesn't have enough power to be a real amp with most sources, or even to power Etymotics to their full potential.
 
Nov 6, 2002 at 9:03 PM Post #7 of 10
The batteries are important, IME. I realize that I'm sounding like a broken record, but the Plainview 9.6v NiMH is the only battery I've found that gets full performance from the amp. It's not simply a question of charge duration. The higher voltage of these batteries is very audible to me, in terms of frequency extension and midrange clarity.

I don't use a DI/O with the RA-1. I use the RA-1 with my portables. The Sony D-303's line out into the RA-1 can drive a Grado HP-1, which is one of the least efficient headphones I own. The RA-1 can also drive the least efficient headphone I've got, the AKG K-1000, as long as you don't expect a lot of volume
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(I don't recommend that particular combination
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)
 
Nov 6, 2002 at 9:03 PM Post #8 of 10
I don't see any reason why the RA-1 would be specifically good with Grados, just because it's made by Grado. Probably the reason Wodgy complains about the bass, is because the amp has practically no capacitance. In contrast, a standard cmoy has hundreds, if not thousands, as much capacitance as a RA-1. So, in deep bass, which requires a lot of current especially in low impedance headphones, there's just going to be no impact.

Also, the amp uses a 30 cent opamp. I doubt Grado went around looking for the best opamp for Grado cans and ended up choosing a 30 cent piece. This is perhaps, the most crucial element of the amp, and Grado couldn't splurge $2 more to get a decent chip in there. $2 more and they could have put maybe 1000uF of capacitance in the amp, more than adequate, and the amp would be so much better.

RA-1 owners, who may wish to upgrade the amp, which would be great, are out of luck. Far as I know, you can't open the box without destroying it.
 
Nov 6, 2002 at 9:23 PM Post #9 of 10
Quote:

Originally posted by Hirsch
The batteries are important, IME. I realize that I'm sounding like a broken record, but the Plainview 9.6v NiMH is the only battery I've found that gets full performance from the amp. It's not simply a question of charge duration. The higher voltage of these batteries is very audible to me, in terms of frequency extension and midrange clarity.


I never used the RA-1 with rechargeables, but most of the Energizer batteries I buy from the store measure between 9.2 and 9.6 V fresh out of the package. Even the lower end of this range is very close to the Plainview's 9.6v at full recharge (just a 400 mV difference).

Also, keep in mind that you can only use Plainviews with Plainview's charger, and you need two Plainview chargers to simultaneously charge two batteries (it takes so darn long to charge each one, you wouldn't want to do them one after the other), so the total cost of the batteries you recommend would be about $45, bringing the "real" cost of the RA-1 to about $400. That's just too much for the level of sound you get. There are $150 all-out Meta42s that just wipe the floor with the RA-1. Even my crazy Meta42 with Black Gates and an Alps Blue and a wooden and steel chassis cost me less than $200, is smaller, lighter and more solid than the RA-1, and it does have the bass impact and sweet treble I'm looking for.
 
Nov 6, 2002 at 9:49 PM Post #10 of 10
To get back to the question...

Makes a lot of sense to ask one of the DIYers at this site for a quote on a META42 (JMT, Tangent, etc... just do a search on META42).

The amp has received very good reviews and would likely come in under your stated budget. The META42 was designed with portability in mind. Could have an amp configured to suit your at-home needs alone (AC only) and/or have one configured to be portable as well (AC or DC powered). Then spend the rest of the budget on music and enjoy!

I don't have your specific source or cans, but in general, a well made amp (like the META42) can improve upon the sound from most sources. I definately notice a difference with Grado 125 straight from my CD player vs with an amp. Heck, even an inexpensive CHA47 improves the sound quality.

Do a search and look at the reviews. I believe there are many folks who have used the META42 with Grado 325 and have posted on the improvement in sound.

mike: batteries vs no-batteries isn't an issue with well made amps. There should be no noise/hum at all from the amp, no matter what the power source.

Good luck!

Bruce
 

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