Ugh just when I thought I was done you guys peaked my interest again.  One day I will have to condense my stream of consciousness for a proper review.  Anyways...


I rolled in two Sovtek 2A3s with two RCAs and have been listening for the last 3 hours. 

This setup may actually be slightly more resolving.  The quad of RCA's has a somewhat gentle ethereal quality.  They sounded great, very open, smooth and relaxing, but it lacked a little bit of umph for me.  I think that is what I noticed when I mentioned rolled off bass with the Amperex 5842.  The impact of the bass was missing.  I also noticed it a little with piano where that percussive impact didn't sound quite as accurate as it had with the full Sovtek set.


Since I thought that the Sovteks were too punchy, I figured I would put them together and see what happens.  As I figured it kind of combines the best of both worlds.  The treble harshness is still mostly gone and the impact has been moderated to a tolerable level that gives instruments a nice weight without being excessive.  The mix match is really a compromise between the two extremes which I shall call the Cold War.  Eastern and Western sounds fighting together with neither side ever really coming out on top.

Just wanted to make it clear, I say fighting for the sake of my analogy.  It doesn't sound like fighting, in fact the sound is still very cohesive.

As I already mentioned bass is noticeably improved.  Very similar to the Raytheon/RCA quad setup but with more subdued treble.  Cymbals are now very slightly bright, however there is some impact which helps to define the strikes better to my ears.  It just sounds more like hitting a cymbal.  This quality carries over to the rest of the instruments, particularly piano and drums.  The RCA quad have a dry sweetness which I really liked.  As you would expect this has been somewhat mitigated by the Sovteks.


This is all very subtle.  I think it speaks to the quality of the amplifier that tube changes can have this type of impact.  I am even more curious about an RCA/EML combo now.  I am not spending more money to mess around with tubes until I have the rest of my system sorted out though (ahem...yggy...ahem).  I really think the tube choice is going to depend a heck of a lot on the rest of the system. I don't want to fiddle around with it and then have to do it all over again in six months.  I am not sure if this type of tube/system transparency will carry over to headphones other to the extent it has with the HD800.  Should still provide decent options for people looking to tube roll and match with whatever gear they have (not the HD700).

The 6CP45 is standard on 445. The 445 production we heard was not using the new production Sovteks (which Craig actually said were kind of sucky.) I think they were the old stock "OTK" / Reflecktor 6CP45.

Not an issue with the sockets. Just need to alter the pinouts. I did check with Craig, current draw is good for both tubes. Although I don't know if he will custom re-wire for you. You can definitely do it yourself.

If you are running purely headphones with the 445, you may be OK with the 5842. The 6C45 have twice as much gain which would be needed for speaker use. It was a matter of the OPT being a little bit less efficient than expected.

Again, don't stress out about it or come to conclusions too quickly. Anax has only heard the Sovtek 6C45s on the 445 development amp, which sounds NOTHING like the 445 production that we heard with the old-stock Reflecktor 6C45s. Anax may very well be right that the 5842 is better, or it may be that the Reflecktor/OTK 6C45 and EML Mesh 45s combination is better. We just don't know at this point.

All I know is that the amp I proclaim as the "GOD amp" had the Reflecktor/OTK 6C45 and EML Mesh 45s. And even then, people's preferences for tubes differ dramatically.

Thanks, purrin,

Now that you pointed out the higher gain, may be I should take this positively.  I will be using the amp for headphones.  Well, I got some 9-pin socket savers.  May be I'll work them into adapters and give myself choices between 6C45 or 5842.             

Craig works in mysterious ways. But we already know that.

I need a drink...