Welcome, Guest. Please Login or Register
Decware Audio Forums
09/21/19 at 00:31:07†


     



Pages: 1
Send Topic Print
Tube rolling in SE84UFO25? (Read 279 times)
Crowes
Verified Member
**




Posts: 16
Tube rolling in SE84UFO25?
09/07/19 at 14:13:02
 
Has anyone rolled the 7DJ8s or SV83s?  Any suggestions or tubes to avoid?  Thank you.
Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 16050
Re: Tube rolling in SE84UFO25?
Reply #1 - 09/07/19 at 14:48:07
 
In my Anniversary Monoblocks the output tubes that Steve tests and matches and supplies are clearly the best.

For input tubes I've settled on 7308s, Amperex, Holland made.
Back to top
 
 

HR-1,ZTPRE,ZBIT,ZROCK2,SE84UFO3-25th, CSP3-25th.Taboo Mk IV+MK III;Rega P3 w/modPS Audio:DMP+DSD,P10,NPC,PowerBases,AC-12 pcs; Mapleshade:SamsonV2+V3,double helix Plus spark cbl;Oppo UDP205;VooDoo:Cremona+Amati,Iso-Pods;MD90-T SE tuner; headphones: PM1,HD800S,LCD-
  IP Logged
Crowes
Verified Member
**




Posts: 16
Re: Tube rolling in SE84UFO25?
Reply #2 - 09/07/19 at 15:49:01
 
Thank you. †I was looking at Matsushita and Telefunkens as an option for the 7DJ8. †I saw that EL84s did not sound good for outputs, so I wanted opinions on the input tube before I spent the $$$.  I love that Mr. Deckert takes the time to choose great sounding tubes.  Perhaps I won't bother ordering an input tube at all!
Back to top
 
 
  IP Logged
JOMAN
Seasoned Member
****




Posts: 363
Re: Tube rolling in SE84UFO25?
Reply #3 - 09/07/19 at 21:02:24
 
Crowes,

I used the SV83 in my SE84UFO2 but in the UFO25 I found that the 6P15EV that are supplied are my preference hands down.  Last I talked to Steve, the NOS input tube that is supplied is a NOS National/Matsushita 7DJ8 and I would recommend getting it from Steve.

Iíve tried a number of different input tubes and gravitate to the 7DJ8/PCC88 types.  A real interesting one is the NOS Tesla PCC88 37 CODE, not the 32 CODE.  I picked up 8 of these for $8.00 ea. after trying one in my CSP3 but canít remember what these were like in the UFO25. In the UFO25 Iím using a Telefunken PCC189.

I have not tried the rectifier that is supplied and now have settled on a rather pricey one so I wonít belabour that but the Mullard GZ34 Fat Base Smooth Plates (not Notched Plates) is considerably less money than the one that I am using.  Still a little pricey but well worth the price of admission IMO. Of all the rectifiers that Iíve tried that one is my second choice.  

Iíd start with what Steve supplies, burn it in and then decide if you even need or want to do any tube rolling.
Back to top
 
 
  IP Logged
Crowes
Verified Member
**




Posts: 16
Re: Tube rolling in SE84UFO25?
Reply #4 - 09/07/19 at 22:09:54
 
@JOMAN which tubes made the greatest difference?  The input, output or rectifier?
Back to top
 
 
  IP Logged
JOMAN
Seasoned Member
****




Posts: 363
Re: Tube rolling in SE84UFO25?
Reply #5 - 09/07/19 at 23:10:50
 
Thatís a tough question to answer as all the tubes make a difference.  Really, the question is which one first?

Based on my experience I would say the rectifier, as the rectifier can effect all the other tubes far more than I realized when I first started and finally learned or realized this with the last rectifier that I tried.

Yes the input tube will make quite a difference but its performances will be limited or enhanced by the rectifier.  More to the point... when I tried the GZ34 Metal Base it made ALL the input tubes far, far, better, even ones that previously I had written off.  In fact, for me it was a sort of an epiphany.  Thatís when I realized the importance of the rectifier.

The other tubes that made a difference were the Voltage Regulator tubes, but I would probably do these last.  These are the cheapest and possibly the ones that I had the most fun with.

So if I were do do it all over again... The 6P15EV that come with the UFO25 are a no brainer, no need to roll these.  First start with the Rectifier, next the input and last the VR tubes.

If you want to see the difference that the input tube makes Iíll give you one of my NOS Tesla PCC88, I have far more than Iíll ever use.  These may not be to your liking but at least youíll see/hear the difference the input tube makes.

However, the rectifier can make the input and output tubes better or worse, and not just a little better or worse.  Itís like the anchor for the entire system.    

A word of caution here... once you start down this road it can be hard to get off of it.  Sometimes ignorance can be bliss, and this amp will be bliss as it comes.  So let it burn in and then decide if you want to do any tube rolling.
Back to top
 
 
  IP Logged
Crowes
Verified Member
**




Posts: 16
Re: Tube rolling in SE84UFO25?
Reply #6 - 09/08/19 at 02:16:31
 
Thank you so much for the information.  My amp is not even being built yet, but I wanted to grab some NOS tubes as the prices are getting ridiculous.  I was considering the Phillips 5R4GRS.  I once purchased one of these for peanuts and gave it away with a preamp that I sold!  It is now selling for over $200, but it is considered a grail for some.  I will look at the one you recommended as well.  Thank you sincerely.
Back to top
 
 
  IP Logged
JOMAN
Seasoned Member
****




Posts: 363
Re: Tube rolling in SE84UFO25?
Reply #7 - 09/08/19 at 02:40:54
 
Crowes,

The GZ34 Metal base has really escalated in price and even when you can get a ďreasonablyĒ priced one your looking at well over $400.00, usually, and I consider that to be a deal.  I managed to pay less. I now have one in my UFO25 and one in my CSP3.

A review worth reading is the Dubs Step Girls Massive Rectifier Review, itís very accurate.

A good alternative to the GZ34 Metal Base is the Mullard GZ34 Fat Base SMOOTH PLATE, not the notched plate.  That is my second choice.  Another one that I consider to be superior to the Philips 5R4GYS (I also had one) is the Sophia 274B Aqua.  I had a bad experience with two of those but others have not, perhaps it was just the two I had, but as a result I was put off new Chinese tubes and went back to NOS.

Be careful though with the NOS rectifiers as a number will only take input cap values of 16uF and that is very risky, 47uF is recommended although Iíve used ones that were slightly lower (40uF) than that as have others.

Otherwise enjoy!



Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 16050
Re: Tube rolling in SE84UFO25?
Reply #8 - 09/08/19 at 18:46:33
 
I would invite experimentation as I honestly believe that room, source, speakers, and cabling at the least all influence how tubes "sound" in a system and one man's "this is the one!" is not necessarily another's. And then there's the concept of "taste" and what one's idea of "natural" or "neutral" is. I've seen enough divergences there to know that is an issue.

There are a number of relatively inexpensive tubes to try and it can be quite educational to roll a number of different types for each position, and when you find a preference for a type, sample a few brands. I have done this over the years and have enjoyed the journey and also wound up in the right "place" for my system.
Back to top
 
 

HR-1,ZTPRE,ZBIT,ZROCK2,SE84UFO3-25th, CSP3-25th.Taboo Mk IV+MK III;Rega P3 w/modPS Audio:DMP+DSD,P10,NPC,PowerBases,AC-12 pcs; Mapleshade:SamsonV2+V3,double helix Plus spark cbl;Oppo UDP205;VooDoo:Cremona+Amati,Iso-Pods;MD90-T SE tuner; headphones: PM1,HD800S,LCD-
  IP Logged
JOMAN
Seasoned Member
****




Posts: 363
Re: Tube rolling in SE84UFO25?
Reply #9 - 09/13/19 at 03:31:01
 
I just tried a Valvo GZ32 in my UFO25 and my CSP3.  I did this not to compare with the GZ34 Metal Base but out of curiosity.  I happened  on this version of the GZ32 and compared it to the CV593/GZ32 and a Mullard pre 60ís GZ32.  Of those three the Valvo (made in France for the German Navy) and the Mullard CV593 were close and in many ways I preferred the Valvo.

Then I put the GZ34 Metal Base back in and the difference was so obvious that I had to post.  Not that the others were bad.  No, in fact I really liked what I heard with the Valvo GZ32 and for $80.00 ea., would be a keeper if I hadnít heard the GZ34 Metal Base.

Itís not about the highs, mids and lows.  The Valvo had good depth and layering.  But what was missing was the decay and liquidity and the details within those attributes that the Metal Base GZ34 produces.  The sound from the Metal Base comes across as a 3 dimensional field that combined with the dynamics, decay and liquidity give the impression of live as close as you can get or, possibly as close as very few tubes can.  Of all the rectifiers I have tried none so far are remotely close.

Everything else is in my amps is the same as with all the other rectifiers I have tried.  Yet none have produced what the GZ34 Metal Base has.

So whatís the point?  Iím not saying that itís the perfect rectifier tube.  Iím not saying to run out and by one and not to experiment, after all these are stupid money now, at least the ones that are up for sale are IMO.  Am I saying that to get the stellar results from the UFO25 you have to have one...NO!

What I am saying is that the GZ34 Metal Base is different and unique.  That there are tubes out there that were special and may never be equaled.  Probably very few.  Maybe the Mullard U52 and Western Electric 422A are another couple that are in that ďspecialĒ bracket, also stupid expensive IMO.  Until you hear one you wonít be able fully understand the difference as these are only words.

I will also say that the the GZ34 Metal Base doesnít make the UFO25 special.  Itís special in itís own right.  If it werenít then the GZ34 Metal base would not be so obviously different.  Itís the UFO25 that shows what that tube is all about and it will do the same with any other tube you try.
 
So experiment if you have the urge to with something more reasonably priced.

Back to top
 
 
  IP Logged
Crowes
Verified Member
**




Posts: 16
Re: Tube rolling in SE84UFO25?
Reply #10 - 09/13/19 at 12:23:47
 
@JOMAN @LON thank you for taking the time to respond.  My UFO25 is being built and you two are making me salivate already!  I was inquiring about tubes because I thought that I would buy a few to have on hand as the prices of NOS are going through the roof.  I will keep my eyes open for the GZ metal base.  I am surprised about the Phillips 5R4GYS as I have heard many people raving about them, but perhaps it is not the best for the UFO25.  I was also considering a Matsushida for the 7DJ8, but it sounds like this is already what comes in the UFO25.  There is a Telefunken I am considering as well, but it seems like Mr. Deckert carefully chooses these tubes and I may just hold off.  Very much looking forward to the UFO25!
Back to top
 
 
  IP Logged
JOMAN
Seasoned Member
****




Posts: 363
Re: Tube rolling in SE84UFO25?
Reply #11 - 09/13/19 at 12:44:01
 
Crowes,

Let the amp burn in.  Donít be in a rush to roll.

The points that Lon makes are valid, factor personal taste into the equation and thatís something that you can only determine by experimenting.  Tube rolling can be an expensive education but it can be rewarding.

Not saying that the Philips 5R4GYS is not a good tube, but itís not the grail and at $200.00 per, thereís definitely better IMO.  The Rectifier review that I referred to is accurate.  Give it a read.  One of the tubes reviewed is the Philips 5R4GYS.
Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 16050
Re: Tube rolling in SE84UFO25?
Reply #12 - 09/13/19 at 14:34:26
 
I agree with John, definitely let the tubes that come with the amp play as the amp burns in. They'll be fine tubes and may end up even being your ultimate choice, as Fats Waller said, "One never knows, do one?"
Back to top
 
 

HR-1,ZTPRE,ZBIT,ZROCK2,SE84UFO3-25th, CSP3-25th.Taboo Mk IV+MK III;Rega P3 w/modPS Audio:DMP+DSD,P10,NPC,PowerBases,AC-12 pcs; Mapleshade:SamsonV2+V3,double helix Plus spark cbl;Oppo UDP205;VooDoo:Cremona+Amati,Iso-Pods;MD90-T SE tuner; headphones: PM1,HD800S,LCD-
  IP Logged
Pages: 1
Send Topic Print