[carusoracer]

With the Dehav, warm up really makes a difference. More than any component I've ever owned.
A good hour should do it IMHO

Thanks for the heads up, I have not listened to it without warming it up for at least 30 minutes until this morning. Quite a difference

[Freo-1]

You will need to give the Mundorf caps some time to break in before assessing the improvement.  They are great caps, to be sure.  I have them in my DIY amps, and they make a big difference. 

[marjrho]

Did he make a recommendation for the 5AW4?

I made contact with George and in short, he said that out of all the rectifier tubes they tested, the 5aw4 tube was the best, and that includes its successor, the 5u4.  Regarding brands, he said that different brands of the 5aw4 may offer a different sound, but it may not translate to better.  I will be speaking with him tomorrow in detail on the topic, and I will write a follow up shortly thereafter.

[SteveFord]

I just heard from Kara and her take was try the 5U4 and see what I think.
As for which manufacturer, they were rebranded so often that it's try them and see what they sound like.
I guess that's what I'll do.

[Tubeburner]

I owned the Ultraverve 3 and found a Hytron 5AW4 to be a excellent rectifier. They are cheap enough and found NOS on Ebay. I also liked a Kenrad 6SN7 in this preamp. Enjoy!

[carusoracer]

You will need to give the Mundorf caps some time to break in before assessing the improvement.  They are great caps, to be sure.  I have them in my DIY amps, and they make a big difference.

Yes, agreed. I have Mundorf Caps in other components, I really like the house sound. This is the first Oil version I have heard from them.
The caps have a good amount of hours on them, which is nice as it eliminates that part of the equation.

[SteveFord]

The previously overlooked rectifier tube does indeed make a big difference in this preamp.
I just popped in a NOS Philco 5AW4 and does that ever sound good!

Thank you, gentlemen, for bringing the rectifier tube to my attention.
So now it's Philco for the rectum fryer, two Sylvanias and an orange lettered 6SN7.
I think my tube rolling days are over with this one.

One last thought - for the 5AW4, if the top is silvered you won't see it glow or at least not very much.

Holy Smokes - that Philco totally transformed the sound of the preamp for the better - detail, highs and dynamics all went up by more than just a little.  Who woulda thought.

[marjrho]

Steve, regarding the 5aw4, you're right, the very top of the tube lights up, and you can't see it through the chrome top.  I found this out by walking right up on the thing and looking under the chrome top, and sure enough, there was light!!

Congrats on the Philco tube, I may have to check that out too.  However, I am going to check out the sophia electric and the RCA red base first.  I will probably order next week.  I will keep you guys posted.

[SteveFord]

I have extras of that Philco so maybe we should put one on an UltraVerve tour?
It's possible my Westinghouse was just beat.
Who wants to try out a 5AW4?  Rules are you post your impressions and ship it on to the next guy.

[carusoracer]

I have extras of that Philco so maybe we should put one on an UltraVerve tour?
It's possible my Westinghouse was just beat.
Who wants to try out a 5AW4?  Rules are you post your impressions and ship it on to the next guy.

Hi Steve,

I would  like to try it out in my UltraVerve. I can post impressions etc.  Just send me a PM for address information.  Let me know

Good to hear that the Rectifier helped. I tried many different 6x4's in my Minimax. Bill at Morningstar is a great Audiophile and knows his tubes. I can't recall how many I had rolled but man you knew it once you found the right combination. Takes everything to another level.

[DARTH AUDIO]

Steve, will you sell one of the extra Philco's? If so, how much? Let me know..

Thanks,

Gary

[SteveFord]

PM sent for your address and no, I don't have any for sale but if you want to try it you can after carusoracer is done with it.

[Emil]

 

Here I was. Perfectly happy in my ignorance of rectifier tubes until now.


Just ordered the Philco.

[SteveFord]

So much for my big tour - I got 4 tubes and two have shorts.
It's a good thing I checked before I sent them out.  Good old eBay.

[Emil]

So much for my big tour - I got 4 tubes and two have shorts.
It's a good thing I checked before I sent them out.  Good old eBay.

Did the ebay seller claim they were tested?

[SteveFord]

No, he claimed they were new.
I have an email in right now and am going to buy a tube tester so I can just do it at home instead of running over to Harrisburg Radio Labs after work.

[SteveFord]

The splendid AVNerdguy (yes, I said Splendid) repaired that pile uh crap tube tester that I got off of eBay and the women folks were gone so I got to play with the downstairs stereo and my new toy (the Sencore Mighty Mite tester).
Lo and behold, I found a Sylvania JAN CHS 6SN7GWT tube packed 4-59 says the box. 
Where did this tube come from?  I have no idea.  I must have bought it or somebody gave it to me or they multiply like cockroaches when you're not looking or something.
At any rate, it tested real good, I swapped out my secret weapon RCA orange lettered tube and we have a winner!
The dynamics which this pre was missing are now there, the soundstage is moved forward, there's not too much bass, there's better detail and the highs are real sharp.
Now it's one Philco rectifier tube and the rest are Sylvanias which is working out really well.
For those who might recall my preamp going up in smoke due to a shorted Philco, both of the Philcos with brown gettering have shorts and are displayed in the Cabinet of Shame. 

[Ericus Rex]

The Sencores are real good at detecting shorts.  What was the problem with your tester?

[SteveFord]

I think Grandpa spilled the last rum and coke of the night into it as he was passing out and then it got parked in the woodshed.
I'm such an honest seller on eBay and I just get hosed every time as a buyer!