[sfox7076]

PX4s sound right for you.

[deuter]

I would rather shoot those 101D tubes with a gun than listen to them...  I have hated them since day 1.

That's funny, just sell them if they are that hated by you.

[deuter]

I recently moved to a new house.  The new listening room is a combination living/dining room - 20ft x 25ft with sloped ceiling front to back going from 8.5ft to around 10.5ft.  Lots of thick carpet.  The old house audio room was 11ft x 20ft x 7-8ft, with hard laminate floor, and a big wall of picture windows.  So, the new room has a LOT less room reflections to deal with and is much more heavily damped.  Needless to say, the system synergy was all wrong for the new house when I set things up.

I've been playing with a lot of system tweaks to try and get things right.  But tube swapping on the Big7 was not high on my list - though it absolutely should have been.  I had originally leaned quite quickly to 300B tubes in the B7.  I hated the stock Psvane 101D from the moment I heard them.  Almost sent the Big7 back under the 1 week trial period - but then a buddy brought over some cheap 2A3 and 300B tubes he had as spares on the last day.  The 300B's were just right.  But what I should have remembered when moving to the new house was how DIFFERENT each of the tubes sounded.  Changing tubes on the B7 doesn't just lead to small changes - the sound signature can change quite dramatically.

But, since I'd invested somewhat heavily in some used Takatsuki 300B's, which are known as probably the best new production 300B's out there, and maybe in the same league as the best of all time, I thought anything I would put into the Big7 in the new house would be markedly inferior.  WRONG...

Last weekend I swapped in some vintage Sovtek 2A3's and RCA Cunningham 45's, as well as giving those stock Psvane 101D's another listen. 

With the Tak's, I had been battling a sound that was just too thick in the midrange, a bit bloated in the bass, and didn't have the attack/transients, or high frequency extension to really open up the sound and engage the listener.  It had really excellent soundstage depth, but the thickness and bloatedness, and lack of attack just made everything sound like the music was not as immediately there - like you were sitting way in back of the hall.

The 2A3's brought some better balance to the sound, more control in the bass, a bit more attack, and a slight bit more high frequency extension.  A bit more "there".  You could hear it wasn't as good of a tube as the Tak's, a certain kind of refined detail was missing, and a touch of a kind of harshness that you know a higher quality tube would do away with.  But the overall sonic signature was a better fit with the room.

The 45's brought even more balance, with more control in the bass, even more attack, good high frequency extension, and awesome soundstage depth to boot.  And a bit higher quality tube than the Sovteks.

The stock Psvane 101D's, really lit things up in terms of upper midrange attack and high frequency extension.  At the expense of some of the balance, and with a very forward dynamic sound that removed that soundstage depth from the 45's.  But a bit of a brittle sound, and strident enough to be fatiguing. 

So, the 45's were the best fit of all these sonic signatures.  I'm really curious what a higher quality 101D would do in my system, knowing that the stock Psvane's are not at all the the same league.  Maybe a Psvane Replica 101D would do it for me.  But those KR 242's or PX4's do sound really interesting to try.  But then again, going with some new production 45's might be interesting as well - I've read a little bit saying the EML 45's are as good or better than any vintage 45's. 

Do any of you guys have any thoughts on the options given what I've said about my impressions above?  I don't think I'm going to be able to afford more than one of these sets of tubes in the near future.

***P.S. I don't want any of the above to be interpreted that I think the Takatsuki 300B is not as good as these cheaper tubes.  Completely on the contrary.  In my other room, I listened to all these same tubes.  And also several other pairs of 300B's, including some NOS AVVT's and Genalex.  The Tak's were heads above the other 300B's in refinement, and also quite a bit higher quality and more refined than the 45's, 2A3's, and 6A3's I tried.  It's just that the 300B sound in the new room is much better damped and also has some bass modes that still need to be tamed.  The 300B sound turns to thick with not enough higher frequency energy to energize the room.  In the old room, I needed a bit of that bass roundness and midrange richness to counteract an otherwise bright room.  Very different situation here - the exact opposite in fact.

Why not ask Lukasz as he would know best given he built the DAC.
Everyone will state preference but given you want to buy one set I would not like to provide any biased opinion.
I will say there are good things said about the PX4 and there is next to none information about the 242.
Lukasz knows the tubes well and should be able to provide you some sound recommendation.

[sfox7076]

That's funny, just sell them if they are that hated by you.

Oh I got rid of them in time.  I have a tube hoarding problem.  I find it hard to send tubes away...  I often find a use for the few ones I have sold... 

[ALRAINBOW]

Good morning all. 
I just got my B7 DAC back. 
It has the following features.
Mundorf copper silver 2.2 cap s
R2r PCM/dsd non switching
SE output two tubes
As it is still running in I would some tube feed back it arrived with the Kron 5u4g , Kron px25
Also does anyone have the psvane we275b recti in the lampi.  Going throw my tubes I found them. 
Also eml mesh 275b if anyone has these tubes or A DAC setup simaler to mine I would appreciate feed back.
So far I hAve two comments the PCM is very nice it is now close to dsd meaning little to no edge anymore. Now I am not sure if it's the combo of it all or not.  But I have rolled many tubes and feel it's the r2r not tubes or even caps .
The next is the background with the stock set is extremly detailed and plays from bal k back ground now better than my msb stack does.
The px25 is a 300b class tube and it took a while of burn in to hear this. It seems the setup,is so detailed it fooled me as to the class of tubes it was.  It seems to hVe the weight of a 300b but still,has the clarity of a 45
So far the stock combo is very nice and I am searching to find others who can weigh in .
Thanks in advance.

[shadowlight]

Raising the thread from the dead. 
I am a proud owner of B7 with R2R upgrade in place, with superclock and DSD 512 upgrade planned for future.  I recently picked up matched pair of JAN CRC 1945 WWII 5R4GY and looking for output tube recommendations (would like to keep the cost under 250 for the pair if possible).  I have a pair of ElectroHarmonix 300B Gold tubes that I am going to roll into the DAC with the JAN rectifier instead of the existing PSvane 101d and Shugang 274b.

I have gone through this thread, the one on Whatsbestforum and Audioshark about tube rolling in B7.  What I am finding is that the px4, px25, kr242, tak 300b, elrog 300b, Lampi eml 45 are the top output tubes with Tak 274b and WE 274b as the rectifier of choice.  The prices on those tubes are out of question so what is the next tier down.

[ALRAINBOW]

Before I through my hat in the ring I have one reccomendation
Buy a solid state recti from any where just to have
You will be surprised how it sounds. Also 300 B tubes can be a bit bloated on the bottom end
The solid state recti fix 'tis and adds some shimmer and overall clarity

Now it's your turn
What speakers do you have
What source do you use
And lastly please describe how it sounds now and what you would like as a change
The recti is about 20 $ try one

[shadowlight]

Before I through my hat in the ring I have one reccomendation
Buy a solid state recti from any where just to have
You will be surprised how it sounds. Also 300 B tubes can be a bit bloated on the bottom end
The solid state recti fix 'tis and adds some shimmer and overall clarity

Now it's your turn
What speakers do you have
What source do you use
And lastly please describe how it sounds now and what you would like as a change
The recti is about 20 $ try one

Sorry, should have mentioned that in my original post.

Speaker: Zu Audio Druid V
Preamp: DIY transformer coupled 4P1L
Source: NAA with HQPlayer
Amp: Triode Lab 2a3 / Response Audio 3205 Extereme (Modified Jolida 302/502) using KT77 as power tubes.


With the 101d I am finding the sound to bit harsh when up converting everything to DSD256.

[ALRAINBOW]

Upsample all ? Even dsd or just pcm ?
Sweet spot for pcm upsample is dsd 512 but 256 is still better.
The 101d is a very analytical tube it needs great stuff to sound good
Not a rock tube but good for classical or small jazz
Also a bit thin in notes thickness. A 45 is mid and better
Your recti are ok but an eml 274b mesh would be better there 45 meal bottle necks are nice
Try eBay for abused pair of eml output tubes used is fine Ina lampi but not for recti unless it's used lightly
A used pair of px242 or 4 is also nice middle ground again used outputs are fine and saves bucks

[shadowlight]

Everything up sampled to dsd 256.  Any particular 45 tube to look for?  Will search ebay on your recommendation.

[ALRAINBOW]

Two
Eml mesh 45 bottle head
Also a 242 by Kron it's rally nice tube relaxed sound a bit heavier is the px4
But please try a solid state as well
It may help a bit with the 101d the

[silverlight]

But please try a solid state as well

Is this safe for the Big7 (and it's tubes)?  I know the output tubes are not running a high voltage, but it's a fast onrush versus a tube rectifier

[wisnon]

No problem when I tried in the Atlantic.

For Recti, try the double mica (ceramic spacer) 5r4gy. Brands are Halton/Zaerix/CIE/Fivre/Brimar etc. EBay and should be less that $50.
Those 1945 JAN RCAs are also well appreciated. New production, try the Kron 5u4g with their very high vaccuum seal.

For output tubes try the vintage RCA 45 tubes from the 1950s (ST shape). National Union is a VERY good brand and they could be even $100 a pair! 6A3 is another inexpensive output tube to try at circa $150 a pair.

The PSVANE metal base 101ds for for $600 a pair. If interested, PM me for a nearly unused pair for a very attractive price.

Good luck!

[shadowlight]

Thx guys, will be on the look out for some of the tubes recommended.

[ALRAINBOW]

Solid state recti are fine for lampi dacs also many Amps as well
But with non lampi stuff always ask the maker
Google solid state recti for lampi I did some posts on them some
Love them but either way of playing back ground music or burning in new tubes or burning in your new dac with crazy tubes it's still very good to have

[sfox7076]

I think the worry is that the B+ will hit the plates before the tube is fully warm and you could get cathode stripping.  Not a huge concern, but because the filaments are constant current, there is a greater risk.  I always worry more about sleeping sickness because the filaments are left on with no B+ In some LampizatOrs.  The cathode is heated and constantly releases electrons. Without a positive plate voltage/current, they build up around the cathode and (unscientificly) reverse the cathode's charge by creating a form of capacitive effect.  It is not going to happen overnight, but the length of time that some people leave heaters on without B+ scares me.  Read more by googling cathode interference resistance.

[ALRAINBOW]

I have both of my lampi dacs shut down the heaters from the button in the front
Like has them on all the time something about loosing an Atom  or something each time we turn them on. For me I will nkt leave any tubes on when nkt home or using it and no Amps either a fail can be destruction of your speakers and some
I do let them all warm up for 30 mins or so from critical playing
What I do know is the b plus is a bit higher ona solid state recti over s tubetubes are half wave I think and recti are four diods so full wave a little more voltage

[sfox7076]

Well, I imagine it is more the voltage drop over the silicon is less than a tube.  Not sure how one would use a bridge instead of half wave by just a drop in. 

[ALRAINBOW]

Sorry I was retarded at at post hahaha. Good trick if one could
Thanks