Advice or Experience with Tube Amps: 485's or KT170's?

I am looking at purchasing a new tube amp to match a set of speakers with 95db efficiency. In this particular setup, I don't think 300b's will give the needed power across the spectrum. This has led to looking at 845 and KT170 tube amps. Both seem to be answers to retaining some of the positive sonic characteristics of the 300b but with the advantage of gaining higher wattage power.  I don't know the strengths or weaknesses of each of these, when comparing sonic attributes.  Can anyone offer advice on this?  Here are some models I have found in searching online:

Mastersound Compact 845 Integrated

Audion Black Shadow 2 Mono Blocks 845

Viva Solistino 845 Integrated

Allnic T-2000 KT170 Integrated

Ayon Triton EVO KT170 Integrated

Thanks in advance for any advice or experience with any of these or with the two tubes in question.



What are your speakers and what is your room size? 95db is very sensitive but hard to know the whole story without knowing the speakers. Also KT170s sound nothing like the 300B tube.

Currently have Daedalus Muse but also buying Wolf Von Longa Son Speakers that are 95db.  I am set on not buying 330b's at this point, so I am looking for class A tubes that have more wattage than 8-10 w.  I do not think most 300b's would be adequate, thus the search for something close to the same end results with broader high and low strengths, i.e. more wattage /power.

I agree with @gregjacob that KT170 sounds rather different from 300B. I've heard a couple 300B amplifier (Takatsuki and AirTight). KT170s have more excitement and 'meat' in their sound. 

There are a couple more highly regarded KT170 options. Jadis I70 and Lab12 Integre4 MKII. I'm using the Lab12. IMO, it is identical in performance to the more expensive Jadis and far easier to live with. I've not heard the Allnic though it seems to be highly regarded.




Thanks for the recommendation.  The LAB12 Integre4 Mk2 Integrated Amplifier now comes outfitted with KT-170 valves and garners some great reviews.  And the price is right.  I have put it on my short list.  I would still like to listen to it side-by-side with an 845 setup like the Viva or Mastersound. But from what I've read, a lot of people on a similar search would apparently be at home and finalized with this Greek amp! Cheers.

@gregjacob Most of the reviews online were for the original version with KT-150 tubes. I've actually tested the amp with both KT-150 and KT-170 tubes. With KT-150s it was a very good amplifier, with KT-170s it was a great amplifier and IMO good enough as an end-game amp regardless of price. With KT-170s there is more weight and smoother sound that overall is more pleasing to hear. 

Nonetheless, do audition and compare as many amps as possible. Different tubes have different sonic characteristics and I know there are those who prefer 300Bs to KT-170s. 

300b is more than enough for 95dB spekers.  I'm driving 95dB with 2.3 watts and it is more than enough. 

There is a damatic difference between an SET and a push pull.  You have the advantage of being able to power your speakers with an SET.   Nice push pull amps cost more, have twice as many tubes, put twice as much heat into the room, and most people think of it as an upgrade.  I consider it a compromse that gives up sound quality to make enough power for an insensitive speaker.  You don't have ain insensitive speaker.

With your budget get a quality hand built 300b and a quality preamp and you'll be very happy.



Thanks Jerry.  I know the tonal qualities of the 300b are the Holy Grail of tube amps. I would have to test a 300b SET with my speakers as 95db is not always the same from speaker to speaker. It sounds like you recommend an amp/preamp setup to the integrated models.  I will be looking and pondering, thanks. 

Have a line magnetic 845 ia.

It's a 22 Watt set amp.Can't

Imagine it getting better.

Hope you find the sound

your after.







@gregjacob I like simple amp circuits.  Handmade.  Look at Aric audio who has gotten a lot of positive feedback here on audiogon although I have never had the opportunity to hear one.  

The amps you listed are all printed circuit board swiss army knives with remotes and lots of features that IMHO mess with the signal path too much.  Aric runs wires from component to component and minimizes everything.

But I assume you want multiple inputs and a remote.  My system uses the DAC as the "preamp" in that it has volume control and multiple digital inputs.  I still need 2 inputs into my amp as I need a pre-in for my HT so I can use the amp to drive the front 2 speakers during HT.  

So I recommend figuring out exactly what you need and finding the simplest way to do it.  and keep it as simple as you can. Aric will make you an amp with 2 or more inputs if that will allow you to skip the preamp.

BTW, there was a thread recently on preamp vs no preamp and I am in the "no preamp" camp but many prefer a preamp.  You can do more damage than good with many preamps so buying a preamp can be challenging.  But the right preamp will sound excellent so that is a personal prefernce.

Unless you are killing your ears with concert volumes I feel certain the 300b will be enough power. 

I am currently having a custom amp built and can connect you with my builder but it will be a lot more money. given the price range of your new speakers you man be interested.  PM me is you are.


As @carlsbad2 mentioned @aricaudio I’ll mention that I own his Super 300B amp. It’s not exactly the data point you are looking for because my speakers are a lot more efficient than yours. I urge you to go to Aric’s website and look at his products. Hand built and point to point wired amplifiers and preamplifiers that are incredible.

Depending on the size of your room and how loud you listen, 8 watts might be all you need. If so, I’d advise to go with an SET of some flavor over push-pull.

@gregjacob - I’ll mention this only in the event that you are not aware of this regarding the Mastersound 845 "Tube bias is factory-set and mustn’t be altered, Ferro stressed, except when changing tubes. "Biasing ... is usually unnecessary for the 845 because these tubes usually work for a very long time. We have our own design of auto-bias circuit that maintains the tubes’ value constant during [their] life. Our triode amps are set at the factory and only need be set again when the power tubes [are] changed." Tubes should, consequently, only be changed by a qualified technician. ". I don’t know if not being able to set bias yourself is an issue for you. Also, the amp comes with the baseline Psvane HIFI series 845 which is a decent 845 , my Line Magnetic 518IA integrated (precursor to the 845IA mentioned above) came with it but their are better 845 tubes.

Also, just simply for context I have Deadalus ArgosV2s which are 97DB vs the 95 DB of the Muse, and the 22wpc of either the LM518IA ( 845set) or 22wpc of my Finale Audio 7189MK2 7189A/EL84M (pp) integrated drive the Argos effortlessly so you shouldn’t have any worries with the Muse. Also, I believe that the Wolf’s have been driven at shows with New Audio Frontiers set integrated amps by Colin King of Gestalt Audio in Nashville. the NAF integrated amps are very well built and nice sounding.

One last thing, Trafomatic's Rhapsody integrated amp is 20wpc 300B. I haven't heard it but below is a link to a bit of information on it from Atlelier 13's website should you be interested in taking a look

Best of luck with whichever integrated or separates you choose.


Thanks for that.  I have been checking out Aric Audio and the Super 211 SET. It looks very good with the build I've been looking for.  The review on 6Moons was thorough and inspiring.  I have not wanted to have to buy a preamp, but the Aric Super 6SN7 Linestage looks like a nice fit as well.  I'm adding this combination to my shortlist.  Would not have found this without you and Carlsbad2. Thanks.  This is what makes this forum so rewarding.  Appreciate you guys.