[jumper]

Hi - I'm starting to shop for an amp upgrade.  My speakers are Philharmonic Audio 3's, since Dennis uses AVA I thought I would check here for recommendations.  I'm currently using a Schiit Yggy and Freya+ through balanced connections (may move on from the Freya but the Yggy is here to stay).  My former amplification was an entry level purchase of a pair of Emotiva XPA-1L monoblocks.  Volume was ok but I feel I was losing low end response and would just like an overall upgrade that won't need to be bettered any time soon.  Budget is the $3K range.

[I.Greyhound Fan]

The FET Valve 400 and the SET 400 would do just fine but I would spend $200 more for the FET Valve 600R with those speakers at 85db and 4 ohms, especially if you like to play it fairly loud.  I have reviewed these amps for Frank and the SET and FET's sound different.  Both are excellent but different flavors.

[jumper]

Thanks for the info, I'll look at and compare the Set 400 and the FET Valve 600R.  I agree the additional power from the 600R would be welcomed.  So there is no Set 600?  Do you recall what the big differences between the Set 400 and Fet 600R were from your auditions?  Thanks!

[JackD]

There is a whole lot more than a $200 difference in price between those two amps.  I own the SET 400 and don't think it would have any problems with your speakers unless your room is really large and you play at extremely loud volumes. I would reach out to Dennis or Frank and ask.  And yes there is a SET 600 but they are monoblocks.

https://avahifi.com/collections/power-amplifiers/products/dva-set-600-mono-block-solid-state-amplifier

[jjss49]

The FET Valve 400 and the SET 400 would do just fine but I would spend $200 more for the FET Valve 600R with those speakers at 85db and 4 ohms, especially if you like to play it fairly loud.  I have reviewed these amps for Frank and the SET and FET's sound different.  Both are excellent but different flavors.

how would you decribe the sonic differences in flavor?  just curious to know... thanks

[trebejo]

With such nice speakers, you'll be fine.

I have a 600R and a V400 on the rack right now, but the room doesn't really let me hear them at their best. So I'll just stick to the ergonomics.

It is easier to manage a solid state rig. I bi-amped the 600Rs back in the day, but now I would only use solid state for such a setup.

If single-amping is how it's going to be, then the 600R looks nice. Since the tubes in the 600R really are pretty easy to manage, there is something very sensible about viewing the input signal as a voltage signal and letting tubes handle that, and the output signal as a current signal and letting the mosfets handle that... as long as the transition is well negotiated and Frank literally got a patent for that.

The V400 might not seem as special since there are a gazillion solid state amps in our lives. One look under the hood and you know you have something special, and then listening to it confirms that and more. And since the V400 costs about $1000 less, it's the easier amp to start with--if it's the best, you're done, and if the 600R is best, then you save up the extra cash and so save the best for last.

It is a nice problem to have, is it not? 

[I.Greyhound Fan]

Thanks for the info, I'll look at and compare the Set 400 and the FET Valve 600R.  I agree the additional power from the 600R would be welcomed.  So there is no Set 600?  Do you recall what the big differences between the Set 400 and Fet 600R were from your auditions?  Thanks!

The SET 400 has a fabulous midrange.  It is slightly warmer and has a romantic sound in my system which consists of a BAT VK-51se tube preamp, Luxman DA-06 DAC and Magnepan 1.6  speakers with dual subs.

The 600R and 400R sound the same. They differ from the SET amps in that they are more neutral sounding and have more air and transparency in the midrange with a wider soundstage. I reviewed  the original FET Valve 400R and 600R's and they have  been improved upon since then for the better.  Keep in mind that tube rolling in the R series can improve  the sound.  I have a friend that has  the 400R and he swapped tubes and the amp does sound better.

Both amps are  musical and dynamic with excellent bass.  I think that the SET has a little more bloom if I remember correctly.  You can't go wrong with either.

There is no SET 600.

By the way, how large is your room and do you  listen at loud volumes?

Larry

[Hydro]

I own the 400R, 600R and SET400. They are all great amps and sound very much alike. If you like to tweek the sound of your systems go with the R amps. Rolling tubes really lets you dial in the sound you like. The 600R has more authority in the bass but the 400R has plenty of power to run my 84db 8 ohm Salk speakers. Franks 30 day return policy lets you buy with confidence.

[I.Greyhound Fan]

I own the 400R, 600R and SET400. They are all great amps and sound very much alike. If you like to tweek the sound of your systems go with the R amps. Rolling tubes really lets you dial in the sound you like. The 600R has more authority in the bass but the 400R has plenty of power to run my 84db 8 ohm Salk speakers. Franks 30 day return policy lets you buy with confidence.

Hydro, that was not my experience with the R series vs the SET amps. I found that they had totally different sound.  I  do agree that the 600R has more authority in the bass.  But these things are very system dependent.  My system is very sensitive to the slightest changes.  On of my local friends who is also a member of AC calls my system "The Truth" because of it.

I think that the OP will appreciate the extra power of the 600R with speakers that are 85db and 4 ohms.  Bass and dynamics will be better but all the amps mentioned will do the job admirably.

[Hydro]

I agree that the SET and R amps do sound different, especially with the stock tubes in the R amp. Both have FET outputs so they have a lot in common. With a 4 ohm load the SET amp will put out about 450 watts compared to 600 watts with the 600R amp, that is about 1 to two db difference, not much on paper but obvious in real life.

[trebejo]

I've had the SET400 plugged in since it got here and the 600R has been sitting unplugged on the same rack. No bad vibes between the amps, no exposing of flaws and all that other finger-pointing stuff that amps do to each other--and I want to keep it friendly like that so the comparator has not been called to duty on this one.

It's all mosfets in the end, so maybe it's like they're cousins, so they should not duel each other. They can just take turns.

[jumper]

Does tube rolling have a very large effect on the 600R?  I do like a detailed sound and would fear steering to far in a tube colored direction.

I have a large room and do at times listen at high volumes so the power would be appreciated. 

[I.Greyhound Fan]

Yes, tube rolling does have an effect on the R series amps. As usual, YMMV. The R amps are very detailed, more so than my Pass X250 amp when I did the review on the R amps.  They are hybrid amps and really do not sound like a tube amp.

[tonyptony]

The SET 400 has a fabulous midrange.  It is slightly warmer and has a romantic sound in my system which consists of a BAT VK-51se tube preamp, Luxman DA-06 DAC and Magnepan 1.6  speakers with dual subs.

The 600R and 400R sound the same. They differ from the SET amps in that they are more neutral sounding and have more air and transparency in the midrange with a wider soundstage. I reviewed  the original FET Valve 400R and 600R's and they have  been improved upon since then for the better.  Keep in mind that tube rolling in the R series can improve  the sound.  I have a friend that has  the 400R and he swapped tubes and the amp does sound better.

Both amps are  musical and dynamic with excellent bass.  I think that the SET has a little more bloom if I remember correctly.  You can't go wrong with either.

There is no SET 600.

By the way, how large is your room and do you  listen at loud volumes?

Larry

Larry, any thoughts on the DVA monos?

[I.Greyhound Fan]

Tonyptony,

The DVA mono's are awesome.  They sound similar but better than the 600R amp.  Very dynamic, musical and effortless.  They will power just about anything.