[robm321]

Quote:

Originally Posted by tmarshl I don't think that you can find a new FirstWatt F1, as Nelson Pass only made 100 of them, but here is a link where you can find a refurbished unit. http://www.marksammut.com/List.html I would also highly recommed recabling the K1000s, perhaps with the Stefan AudioArt Exinox hardwire cabling: http://www.stefanaudioart.com/K1000CableHardwired.html There is a 10-11 week wait for this cabling, due to high demand.....but it's worth the wait - IMO nothing comes close

I will definately recable it eventually - I noticed the F2 - is there something about the F1 that makes it better suited to the K1000s over the F2? It's only $100 difference.

 

[tmarshl]

Quote:

Originally Posted by robm321 I will definately recable it eventually - I noticed the F2 - is there something about the F1 that makes it better suited to the K1000s over the F2? It's only $100 difference.

Nelson Pass told me that either the F1 or the F2 would do a good job with the K1000s. I don't think that you can go wrong.

 

[Nomad]

F1 and F2 are "current driver" amplifiers and both of them will work great.
Actually the F2 should sound a bit more "tubey" but I'm not sure if it will best the F1.
The F3 is a different animal. It's a "voltage driver" amp, like conventional ones.

Edit: The schematics of F1 were released to the public (Nelson Pass is really a great guy) so you might be able to build it yourself or make it built for someone on DIYAudio for less money. The schematics of F2 should be released anytime soon. As soon as the 100 unit run is sold out.

 

[robm321]

Quote:

Originally Posted by Nomad F1 and F2 are "current driver" amplifiers and both of them will work great. Actually the F2 should sound a bit more "tubey" but I'm not sure if it will best the F1. The F3 is a different animal. It's a "voltage driver" amp, like conventional ones. Edit: The schematics of F1 were released to the public (Nelson Pass is really a great guy) so you might be able to build it yourself or make it built for someone on DIYAudio for less money. The schematics of F2 should be released anytime soon. As soon as the 100 unit run is sold out.

Thanks Nomad, tmarshl - good information

 

[kwkarth]

Quote:

Originally Posted by Edwood Well, they did commission SAC to make a dedicated headphone amp for it. And FWIW, even though it had balanced inputs, it was essentially a single ended output, as the grounds were tied together. -Ed

The grounds are not tied together on my SAC. I wonder if they had different versions?

 

[NU62]

I'm driving my K1000s with an Almarro A205A (4.8 watts single ended EL84 pentode integrated amp). This amp generates more than enough power for these phones and the sound is outstanding. If you get a Almarro A205A order it with a 1/4" headphone jack on the front instead of the mini jack on the back; you may pay a little more but it's worth it re the sound and convenience. I concur with everyone who recommends the Equinox cable upgrade for the K1000 - I am using the tail wire version with 1/4" plug termination - the build quality and sound improvement vs the stock tail wire is substantial.

 

[JzzMaTzz]

tmarshl, are you driving the F1 balanced? Nelson Pass says it's a whole different animal in balanced mode. To go balanced you would have to start from a balanced source and so on down the line.

For those interested in the F2, here's a review link

http://www.6moons.com/audioreviews/firstwatt2/f2.html

 

[tmarshl]

Quote:

Originally Posted by JzzMaTzz tmarshl, are you driving the F1 balanced? Nelson Pass says it's a whole different animal in balanced mode. To go balanced you would have to start from a balanced source and so on down the line. For those interested in the F2, here's a review link http://www.6moons.com/audioreviews/firstwatt2/f2.html

Dear JzzMaTzz,

I did a little research, and yes, I am driving the F1 balanced [Digital Coax connection between transport and DAC - XLRs from that point on]. I would agree with Nelson that it is a totally different animal in balanced mode.

 

[JzzMaTzz]

Quote:

Originally Posted by tmarshl I don't have a balanced source (yet) but I am working on it. So I am not running fully balanced. I am using XLR interconnects between the DAC/preamp and the F1, and even that makes a difference.

I haven't gone balanced myself yet, still looking for the right preamp, possibly a balanced placette RVC. BTW what cables and powercord are you using?

 

[tmarshl]

Quote:

Originally Posted by JzzMaTzz http://www.6moons.com/audioreviews/f...irstwatt3.html

I am driving my K1000s (hardwire cable upgrade from Stefan AudioArt) with the FirstWatt F1. fully balanced. I concur with the review. I have never heard such natural, realistic, detailed sound from a pair of headphones (earspeakers). As a result, I sold my Omega II/KGSS combination.

I could not recommend the k1k/F1 combination more enthusiastically!

 

[jessica_fae]

Quote:

Originally Posted by Michael G. What everyone seems to agree, on sooner or later, is that high current rather than raw power is the ticket. And, some of us seem to be finding out that "speaker based" amps, with headroom to spare, just-so-happen to be the ideal amps that are truly capable delivering the combination of high-current *and other things slightly mysterious* that the K-1000's need...

I think this is the same phenomenon that I experienced with my Acoustat 1+1 ESLs. ESLs are very hard to drive well because they effectively look like a capacitor to the amplifier or drop to 120ohms in the bass frequencies. The result of years of reviewers playing with this is the same conclusion, either go for super high current solid-state amplifier or low power tubes (or the Nelson Pass designs like the Aleph3 or decendents).

Here is a great article that I think probably nails this magic down best
http://www.atma-sphere.com/papers/myth.html
The essence of this is that transistor amps are designed around constant voltage - which is why the power curve changes with impendence, while tube-transformer/tube-OTL/single-ended transistor amplifiers aim for constant (but lower) power.
Quote:

Let's say you have a high quality 150/channel transistor amp. 150 watts into 8 ohms, a reasonable amount of power, but if you have a four Ohm speaker its 300 watts. Nice. Into 2 Ohms, if the amp doesn't blow up or current limit, 600 watts. So what does the amp produce driving 16 Ohms? 75 watts. Into 32 Ohms its only 35 watts! This could result in serious problems were the speaker a typical electrostatic, where such impedances are common in the bass frequencies. This explains why transistor amplifiers are usually such a poor match for electrostatic speakers. ... This is what the right OTL can do into these impedances: 150 watts into 8 ohms, 145 into four (less than 1/2db difference), about 80 watts into 2 ohms, but into 16 we have 149 watts, into 32 ohms 145 watts- so you see that as long as the speaker load is moderately well behaved, this OTL example produces far more linear power over the same range of impedances, whereas the transistor amp is quite simply incapable of being linear at all. ... The reason has to do with the vanishingly small output impedance of the transistor amp.... The result is that the transistor amp has what is called a constant voltage characteristic, not constant power, which is of course what a power amp should do.

My instinct is that amplifiers that are good for electrostatic loudspeakers will be good for the K1000, but none of these are cheap.
Pass Aleph 3
GoldenTube SE40
40-50watt EL34 / 6550 / KT88 / 6L6 based push-pull amps from the likes of Cary Audio, ConradJohnson, AudioResearch, SonicFrontiers, RogueAudio, Anthem, JoLida, Antique Sound Labs
Atmosphere S-30
Cary CAD300se
Balanced Audio VK55 VK60 or VK75

Or the recomendations that pop up here
FirstWatt F1/F2
Antique Sound Labs MG OTL 32 DT

I have a K1000 arriving soon so I'll be able to give my impressions of the K1000 / GoldenTube SE40 combination soon.

-Jessica

 

[PeeeMeS]

Anyone have experiences with driving the K1000s with the LaRocco Headcode?

 

[tmarshl]

Quote:

Originally Posted by jessica_fae I think this is the same phenomenon that I experienced with my Acoustat 1+1 ESLs. ESLs are very hard to drive well because they effectively look like a capacitor to the amplifier or drop to 120ohms in the bass frequencies. The result of years of reviewers playing with this is the same conclusion, either go for super high current solid-state amplifier or low power tubes (or the Nelson Pass designs like the Aleph3 or decendents). Here is a great article that I think probably nails this magic down best http://www.atma-sphere.com/papers/myth.html The essence of this is that transistor amps are designed around constant voltage - which is why the power curve changes with impendence, while tube-transformer/tube-OTL/single-ended transistor amplifiers aim for constant (but lower) power. My instinct is that amplifiers that are good for electrostatic loudspeakers will be good for the K1000, but none of these are cheap. Pass Aleph 3 GoldenTube SE40 40-50watt EL34 / 6550 / KT88 / 6L6 based push-pull amps from the likes of Cary Audio, ConradJohnson, AudioResearch, SonicFrontiers, RogueAudio, Anthem, JoLida, Antique Sound Labs Atmosphere S-30 Cary CAD300se Balanced Audio VK55 VK60 or VK75 Or the recomendations that pop up here FirstWatt F1/F2 Antique Sound Labs MG OTL 32 DT I have a K1000 arriving soon so I'll be able to give my impressions of the K1000 / GoldenTube SE40 combination soon. -Jessica

Here is a review of the ASL MG OTL 32 DT with the K1000s:
http://6moons.com/audioreviews/asl/32.html