Nelson Pass First Watt F4

anubisgrau · « **on:** 24 Jul 2007, 12:11 pm »

Hi everyone,
I've decided to go the high eff. speakers road and purchased myself a pair of absolute beauties: Living Voice Air Partner horns. Here they are (still in the warehouse though):
http://www.b92.net/tmp/goc.htm

I used to have Promitheus TVC but I've sold it now so I stick to my trusty EAR 864 active preamp.
I am now in a search for a good, quiet amp for my 105dB horns so I am actually highly intrigued by the First Watt F4 design that could be quiet enough to work with a feed from my preamp.

I am wondering if anyone had a chance to try it somewhere. Also I think I've seen $2000 RRP stated however I'm curious if anyone has an estimation of the parts price to DIY it.

Cheers Anubis

sts9fan · « **Reply #1 on:** 24 Jul 2007, 12:23 pm »

Using all top of the line parts you could still make a stereo F4 for under a grand. Peter Daniels did a run of boards that look really nice. Now I just need the time to build up the amps. It will have to wait till after the Zen9 first though.

Srajan Ebaen · « **Reply #2 on:** 24 Jul 2007, 01:21 pm »

Anubis,

got an e-mail this morning from Nelson, saying that a pair of F4s were enroute to my digs for review. I take that to mean that production just commenced so I'd be surprised if many people have yet heard a full production sample though DIYers of course have been building F4s and derivatives for a while...

macrojack · « **Reply #3 on:** 24 Jul 2007, 01:22 pm »

Anubis - I see you are also seeking an Altmann BYOB. Pardales, an AC member posted at one time that he had the RWA Sig 30 and the BYOB in his home at the same time. He said they were very close but he kept the Altmann. I think that was due to ease of return to Connecticut vs. Germany. I'm not certain of that though.
Before I bought my Sig 30, I had a Pass Aleph 30 which I've heard is the foundation for all the First Watt models. The Siggie was quieter than the Aleph.

None of this answers your question directly but it's the best I can do. The Sig 30 option is accessible and carries a very small amount of financial risk if you are in the U.S.

Chances are they will all be quieter than that preamp.

doug s. · « **Reply #4 on:** 24 Jul 2007, 01:45 pm »

another choice would be an almarro a205a mkll. i have one & it's dead quiet w/my 97 db efficient 14 ohm coincident victory's. of course, it makes beautiful music when it's not being dead quiet.

swapping out two caps & installing better tubes, (there's only three, so it's not cost prohibitive to do tube swapping), make it a top-class amp, imo, competitive w/some of the best. at $800 retail, it's a freaking bargain as well. i got mine used, w/hovland musicap upgrade, for <$600 shipped. other mods are bypassing the dual input jacks, & the wolume pot, but w/these, you can use it as an integrated amp as well... (i have always used it as amp, only.) it, & the earlier non-mkll iteration both got swell reviews by one of srajan's 6moons buddies...

doug s.

Imperial · « **Reply #5 on:** 24 Jul 2007, 08:31 pm »

I'm gonna make an unusual suggestion here. But I believe it to be important to check out this!
Slip Gary Dews (Border Patrol) an e-mail and tell him what kind of speaker you are getting Anubis.

Then you tell him that you cant quite swing the price of his Sweet amps but want to know what kind of mono
amps he would recommend for your Partners and if it would be possible to upgrade those with his powersupplies.
Border Patrol has an AWESOME "add on" powersupply that will simply transform any small wattage tubeamp they are connected to!
I believe that the large behemoths you are getting are quite hungry, despite their diminutive obvious needs.
The amps better have some serious balls as I have been able to ascertain
Checking out the Border Patrol site will sort of explain a lot... I feel..

Other than that, here is a Living Voice/Vitavox page with some nice info on the beauties! (LV Air Partner)
http://website.lineone.net/~empson/featuring_Vitavox.html
It appears that you have stumbled upon a set of "Statesman"!
Well, the big LV's do electronica and even dancetracks with aplomb!

Imagine that...!

Imperial

anubisgrau · « **Reply #6 on:** 26 Jul 2007, 09:45 am »

hi, many thanks - i don't think this is anything unusal on contrary border patrol 300b amp is the most famous synergy match for LV speakers (apart from kondo's:))..... also a combo of art audio power amps such as diavolo enhanced with the BP power supply.... thanks anyway, the only problem is that this is slightly out of my budget at present after purchasing APs...

no, my piece is not a statesman but the latest version of the normal APs, with a slot 2405 tweeter put into a mouth of a big bass horn, here is the pair i've got:

http://www.b92.net/tmp/goc.htm

Quote from: Imperial on 24 Jul 2007, 08:31 pm

I'm gonna make an unusual suggestion here. But I believe it to be important to check out this!
Slip Gary Dews (Border Patrol) an e-mail and tell him what kind of speaker you are getting Anubis.

Then you tell him that you cant quite swing the price of his Sweet amps but want to know what kind of mono
amps he would recommend for your Partners and if it would be possible to upgrade those with his powersupplies.
Border Patrol has an AWESOME "add on" powersupply that will simply transform any small wattage tubeamp they are connected to!
I believe that the large behemoths you are getting are quite hungry, despite their diminutive obvious needs.
The amps better have some serious balls as I have been able to ascertain
Checking out the Border Patrol site will sort of explain a lot... I feel..
Other than that, here is a Living Voice/Vitavox page with some nice info on the beauties! (LV Air Partner)
http://website.lineone.net/~empson/featuring_Vitavox.html
It appears that you have stumbled upon a set of "Statesman"!
Well, the big LV's do electronica and even dancetracks with aplomb!
Imagine that...!

Imperial

jaspal kallar · « **Reply #7 on:** 26 Jul 2007, 12:34 pm »

Quote from: macrojack on 24 Jul 2007, 01:22 pm

Anubis - I see you are also seeking an Altmann BYOB. Pardales, an AC member posted at one time that he had the RWA Sig 30 and the BYOB in his home at the same time. He said they were very close but he kept the Altmann. I think that was due to ease of return to Connecticut vs. Germany. I'm not certain of that though.

I PM'ed Pardales about his experiences of Sig 30 vs the Altmann BYOB sometime ago.. He replied with saying he kept the BYOB amp since it had better flow, and was just smoother. He also mentioned that the differences between the two was not much.

jaspal.

danubs · « **Reply #8 on:** 26 Jul 2007, 02:36 pm »

Hoping to build my F4 soon (diy). F4 bit different than Aleph's. Think somewhere in the manual or maybe it was in the thread where Nelson stated something along the lines that idea not really anything new, just surprisingly not done nor offered. Likely due to the 'power buffer' nature of it. The few comments i've read was that it is very transparent (oh these words).

anubisgrau · « **Reply #9 on:** 26 Jul 2007, 02:46 pm »

Quote from: Srajan Ebaen on 24 Jul 2007, 01:21 pm

Anubis,

got an e-mail this morning from Nelson, saying that a pair of F4s were enroute to my digs for review. I take that to mean that production just commenced so I'd be surprised if many people have yet heard a full production sample though DIYers of course have been building F4s and derivatives for a while...

Thanks Srajan, looking forward to hear your thoughts on it. Certainly one of the freshest ideas to appear on the market of low power high efficiency products in ages!

Srajan Ebaen · « **Reply #10 on:** 26 Jul 2007, 05:49 pm »

Nelson would be the first to admit that the idea per se isn't novel at all - just that he's the first to be nuts enough to actually turn it into a commercial offering

sts9fan · « **Reply #11 on:** 26 Jul 2007, 06:16 pm »

Is that new Musical Fidelity jammy similar?
http://www.musicalfidelity.com/products/supercharger/whatis.html

JoshK · « **Reply #12 on:** 26 Jul 2007, 08:39 pm »

I really think it (F4) is one of the most practical ideas to come along in a while. So many of us audiophiles like our tubes, especially the tube preamps. But tube preamps have far too much gain when combines with a full gain (26db) amp. So why not let the preamp do the gain and the amp do the powering (current gain)? Reasonable enough thought. John Broskie wrote some about this on his blog, even in response to NP's commercialization.

doug s. · « **Reply #13 on:** 26 Jul 2007, 08:42 pm »

josh, here's an easy solution to situations w/too much gain:

http://cls.audiogon.com/cgi-bin/cls.pl?accstwek&1189785173

doug s.

Quote from: JoshK on 26 Jul 2007, 08:39 pm

I really think it (F4) is one of the most practical ideas to come along in a while. So many of us audiophiles like our tubes, especially the tube preamps. But tube preamps have far too much gain when combines with a full gain (26db) amp. So why not let the preamp do the gain and the amp do the powering (current gain)? Reasonable enough thought. John Broskie wrote some about this on his blog, even in response to NP's commercialization.

JoshK · « **Reply #14 on:** 26 Jul 2007, 09:04 pm »

doug... IMHO that is at best a bandaid, and at worst a terrible idea. More gain than needed is like throwing the baby out with the bathwater. No matter how perfect your component is, every gain stage adds a layer of crap let's say (distortion, haze, opaqueness). The higher the gain the worse typically. So if you have more gain than you need, you've significantly lowered your signal to noise ratio and most likely you've deteriorated your system more than need be. So shunting extra gain to ground is far less than ideal...even worse, typically shunting via resistors adds its own noise and almost always kills dynamics.

anubisgrau · « **Reply #15 on:** 26 Jul 2007, 09:06 pm »

spot on, you beat me in with it. in-line attenuators are one of the worst things in a transparent system (horns etc).

doug s. · « **Reply #16 on:** 27 Jul 2007, 01:54 am »

i have used these with amps that have extremely high input sensitivity, with no ill effects. they're plugged into the amps, w/the input interconnects plugged into them directly. from the mfr:

"...When used with pre/power amps, there is an added benefit. Although the attenuators can be used on the inputs of the pre-amp in exactly the same way as they would be used on an integrated amp (with the same benefits), alternatively they can be used between the pre-amp and the power amp to even greater effect. When used this way, not only is system gain reduced by 10dB, but the signal to noise ratio is improved by 10dB. This pushes the noise floor down enough to create an inky black silent background from which the music can emerge with better resolved fine detail and transparency. This applies to even very high-end and very expensive pre/power amps.... ...These attenuators give real, measurable as well as audible improvements..."

in fact, this has been my experience, using these in this manner.

ymmv,

doug s.

Quote from: JoshK on 26 Jul 2007, 09:04 pm

doug... IMHO that is at best a bandaid, and at worst a terrible idea. More gain than needed is like throwing the baby out with the bathwater. No matter how perfect your component is, every gain stage adds a layer of crap let's say (distortion, haze, opaqueness). The higher the gain the worse typically. So if you have more gain than you need, you've significantly lowered your signal to noise ratio and most likely you've deteriorated your system more than need be. So shunting extra gain to ground is far less than ideal...even worse, typically shunting via resistors adds its own noise and almost always kills dynamics.