CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS

Lobby => Head Amps, DACs, Sources, Portable Equipment Discussion => Topic started by: MuppetFace on February 23, 2013, 03:59:58 PM

Title: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on February 23, 2013, 03:59:58 PM
I figured we could use a thread to collect helpful t00b-related info. So, without further adieu...


The Pirate's TUBE Resource Thread!


Please feel free to share advice on what to look for and where to find a good selection, links with good deals, opinions on which tubes are worthwhile and which aren't, etc. etc. There are plenty of amps out there, but among pirates there are undoubtedly favorites that have become something of a "pirate's canon."
 :boom:


It would be great if we could collect some recommendations for what tubes work best with these amps. Additionally many amps can be tailored to suit specific headphones just by changing the tubes, so any recs for what works best with certain headphones would be beyond awesome.


You know those wine blurbs you see at decent liquor stores, the ones that describe what the wine's characteristics and flavor profile are like? If we could have something to that effect for peoples' favorite tubes, I think that would be really fun too.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on February 23, 2013, 04:07:45 PM
Here are a few links to other tube threads here on Changstar:

EL34s -> http://www.changstar.com/index.php/topic,816.0.html

ECBA tube rolling -> http://www.changstar.com/index.php/topic,430.msg7349.html#msg7349
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Valentin Hogea on February 23, 2013, 04:27:34 PM
I got lots to share if someone interested in 6AK5; 6AS7/6080/5998; 6SL7; 6SJ7-type tubes...


However the EL34-thread I started. Very limited experience (to avoid saying none...)
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: burnspbesq on February 23, 2013, 06:13:00 PM
Back in the days of my love-hate relationship with a RSA Raptor, I found Upscale Audio to be a great source for tubes.  Kevin is something of an acquired taste, but his inventory is to die for and his prices are not outrageous.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on February 23, 2013, 07:10:01 PM
I've got the LG coming my way soon-ish, so I'm really starting to get invested into this whole tube rolling thing. Which is a first for me. I've messed around with it in the past, but it was always more of a chore and something I didn't want to bother with really. My feelings are changing.

I want to pick up an assortment to start out with on the LG, so I'm looking for 6SN7 / 6CG7 recommendations primarily. dBel recommended I look into 12SN7 too.

When I heard some 1950s Sylvania black plates in the LG I feel in love. I really want to find a pair of those in particular.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: gurubhai on February 23, 2013, 09:29:26 PM
I'll be keeping an eye on this thread as well for 6SN7/6CG7/ECC82/6080 recommendations for my upcoming DIY amp. Keep it rolling!
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: dBel84 on February 23, 2013, 10:27:26 PM
I am afraid that I don't keep "tasting notes" but a couple of gems from times past that come to mind :

12AU7 variants:
GE 6080
RFT ECC82
GE 5963

edit :: how could I forget the philips miniwatt 12au7

Noval variants of 6SN7
RCA clear top 6CG7 / 6FQ7


6SN7/12SN7:
Tari's Mullard ECC32
BL63 is similar to above but needs an adapter and has a MUCH higher heater current demand than even the ECC32. Alex modified the LGs power supply just before it went into production to be able to handle this tube. 
Sylvania GT ( 1950's ) including the JAN VT231
CBS / Hytron long tube versions - also 50's production.

Happy surprises
Coin base sylvanias - often cheap and very similar to the 50's GT

The following are links to a few useful threads out there


The Reference 6SN7 Thread   http://www.head-fi.org/t/117677/the-reference-6sn7-thread

The 6SN7 Identification Guide     http://www.head-fi.org/t/209782/the-6sn7-identification-guide

6SN7 Tube Addicts   http://www.head-fi.org/t/479031/6sn7-tube-addicts

Toob Madness Or The 6SN7 Zoo   http://www.enjoythemusic.com/magazine/equipment/0304/6sn7.htm

BRENT JESSEE  http://www.audiotubes.com/6dj8.htm

Joe's Tube Lore   on audioasylum  http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html


I am sure there are plenty more out there too .


My biggest problem with people describing tubes is that most amp topologies differ and thus people are describing tubes under significantly different conditions and it is a far cry to extrapolate from one person's experience running a 6SN7 at 200V with 5mA bias to another running the same tube at 350V with 15mA bias. Not to mention design differences in amps - transformer coupled, cap coupled, hybrid , B+ that is regulated or choke filtered ......... I think you see my point.

..dB
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Ringingears on February 24, 2013, 01:49:37 AM
I have purchased several tubes from Jim McShane. Always have been satisfied with the quality and all are tested beforehand. Lots of differents types.

http://www.mcshanedesign.net/tubes.htm

Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Valentin Hogea on February 24, 2013, 02:25:44 PM
My 6SL7-findings...


Mullard ECC35 Tall Black Base 50's-60's
Bass quality: 5/5
Bass quantity: 5/5
Mids quality: 5/5
Mids quantity: 4/5
Treble quality: 5/5
Treble quantity: 4/5
Imaging: 5/5
Sound stage: 5/5 Deep, wide and tall
Price: 240-300 USD


In short: Best so far. Truly fantastic. If you only need one for your amp. This is it.


Mullard ECC35 Short Brown Base 50's-60's

Bass quality: 5/5
Bass quantity: 4/5
Mids quality: 5/5
Mids quantity: 5/5
Treble quality: 5/5
Treble quantity: 3/5
Imaging: 4,5/5
Sound stage: 5/5 Deep, wide and tall
Price: 240-300 USD


In short: A bit more muddy/warm than the Tall Black Bottle ones. Maybe a bit more "high-end" Leben-ish. Unmodded HD800 / Bright headphones overall I'd say


Ken-Rad VT-229 Tall Black Base 40's

Bass quality: 4/5
Bass quantity: 4/5
Mids quality: 4/5
Mids quantity: 3/5
Treble quality: 4/5
Treble quantity: 3/5
Imaging: 4/5
Sound stage: 4/5 Somewhat smaller than the above
Price: 100-120 USD


In short: A bit more refined than the RCA one, but not that big of difference.


RCA VT-220 Tal Black Base 40's


Bass quality: 3,5/5
Bass quantity: 4/5
Mids quality: 4/5
Mids quantity: 3/5
Treble quality: 4/5
Treble quantity: 3/5
Imaging: 4/5
Sound stage: 4/5 Somewhat smaller than the above
Price: 70-100 USD


In short: Very similar to the Ken-Rad one. Good all-round tube.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Valentin Hogea on February 24, 2013, 02:28:35 PM
My findings on 6AK5-type tubes:

http://www.headfonia.com/high-octane-fuel-for-the-pan-am-a-tube-rollers-notes/3/
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on February 24, 2013, 02:38:35 PM
Picked up two pairs of 12SN7s for a pretty good price just now, some Hytron and Sylvania GTs from the 1950s.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: ader on February 24, 2013, 03:46:47 PM
In the other thread last night I was asking about your plans with rolling 6SN7's in the Electra specifically since you'd have to buy matched sets of 4 for it (I assume).
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on February 24, 2013, 05:53:19 PM
In the other thread last night I was asking about your plans with rolling 6SN7's in the Electra specifically since you'd have to buy matched sets of 4 for it (I assume).

I have a few amps that use 6SN7s, so buying a quad is probably the way to go anyway since I can use them for the others as well as the Electra.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: CEE TEE on February 25, 2013, 02:34:58 AM
I have incoming PX4 tubes with a B4 base.
The 300B use a UX4 base.
Has anyone seen this socket from Yamamoto?

Yamamoto TEFLON UX4-B4 Socket (http://www.jacmusic.com/sockets/Socket-Yamamoto.htm)

EDIT:  Craig said this to someone who asked him about this socket...

http://www.head-fi.org/t/497049/balancing-act-tube-rolling#post_6711695

Quote:
Yes that is a genius product, very cool. If I had known about that I would have made the metal for that socket. The Yamamoto has a different mounting ring, and mounting hole spacing. The socket has to be machined to fit the BA, or a new top plate has to be made.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: twifosp on February 26, 2013, 04:14:07 PM
Anyone have info on super7 tube rolling and the resulting sound signatures?
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Tari on February 26, 2013, 04:33:44 PM
Check this (http://www.changstar.com/index.php/topic,7.0.html) post/thread.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: twifosp on March 08, 2013, 10:05:31 PM
Anax & CEE TEE  what do you guys have in your S7s these days?
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: IamwutIam on April 02, 2013, 01:26:31 PM
I've had great success getting my NOS "glass" through Tubemongers. They can be a bit "pricey" but I've been dealing w/ them for a few years now & I have'nt gotten any bad tubes(or any I've not been satisfied w/ for that matter) yet.

Hey, what else can we spend money on that gives back as much enjoyment, time after time
(Now that I stated this, watch... The pair of Mullard '61 wrinkle glass CV4035/12AX7s I have in transit(these things have too many damn numbers) won't be up to the "standards" of all the other tubes I've gotten; I should delete this before I jinx my success rate)
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: MuppetFace on April 02, 2013, 01:47:37 PM
I've been using eBay for tubes lately. Results have been mixed.

The experience of buying individual matched pairs has been positive so far: Sylvania and Hytron 12SN7s and Marconi 6SN7s arrived well packaged and as specified from three individual sellers.

However I also ordered a small lot of 15 or so 12SN7s from another seller, and the packaging on this left much to be desired. Basically the tubes were thrown into a box filled with packing peanuts, completely loose without any wrapping around each tube. Several of them were damaged and rattle when inspected. Could have at least wrapped them in tissues or something to keep them from smashing into one another during transit.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: shipsupt on April 02, 2013, 02:00:27 PM
I've generally had really good luck with small lots from e-bay, but I remain pretty picky about who I buy from and I often grab "Buy it Now" deals at realistic prices instead of going on the cheap in an auction.  I usually stick to the lower priced tubes as well, leaving the high price stuff to dealers etc...

That said, I miss having my tester, it's still back in the US.  I got a quad of Tungsol ECC83's for the GES and they are causing me to occasionally blow a fuse.  Without the tester I don't have a good way to check them out.  Of course they were the best tubes I had for the GES by far. 

Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: IamwutIam on April 02, 2013, 04:25:01 PM
I've generally had really good luck with small lots from e-bay, but I remain pretty picky about who I buy from and I often grab "Buy it Now" deals at realistic prices instead of going on the cheap in an auction.  I usually stick to the lower priced tubes as well, leaving the high price stuff to dealers etc...

That said, I miss having my tester, it's still back in the US.  I got a quad of Tungsol ECC83's for the GES and they are causing me to occasionally blow a fuse.  Without the tester I don't have a good way to check them out.  Of course they were the best tubes I had for the GES by far. 


I've been using eBay for tubes lately. Results have been mixed.

The experience of buying individual matched pairs has been positive so far: Sylvania and Hytron 12SN7s and Marconi 6SN7s arrived well packaged and as specified from three individual sellers.

However I also ordered a small lot of 15 or so 12SN7s from another seller, and the packaging on this left much to be desired. Basically the tubes were thrown into a box filled with packing peanuts, completely loose without any wrapping around each tube. Several of them were damaged and rattle when inspected. Could have at least wrapped them in tissues or something to keep them from smashing into one another during transit.

It seems a lot of you use EBay to find your tubes. I'm guessing you are getting better prices, but I would get discouraged real quickly if I did'nt receive visibly perfect, well packaged tubes every time, screw the price. ( I justify the prices for myself, by the fact I usually replace tubes to try "different flavors" when the sound starts moving past neutral & slightly toward dull)

Discovering "Tubemonger" may be the only good thing I got from "Head Fi". (& it's kind of surprising I came across mention of it, as the group over there were buying most of their tubes from each other  & one particular gentleman who appeared to be using the thread as "his store"; they had a version of "Tube Old Boys" over there.)

Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Anaxilus. on April 02, 2013, 06:21:01 PM
I buy from sellers w/ >99% feedback that also have 14 day return policies.  You can't go wrong, never had a problem unresolved.  If any issues arose, they usually resolved better than I could have hoped for. 
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Mr.Sneis on April 03, 2013, 08:06:38 PM
I've had great success getting my NOS "glass" through Tubemongers. They can be a bit "pricey" but I've been dealing w/ them for a few years now & I have'nt gotten any bad tubes(or any I've not been satisfied w/ for that matter) yet.

Hey, what else can we spend money on that gives back as much enjoyment, time after time
(Now that I stated this, watch... The pair of Mullard '61 wrinkle glass CV4035/12AX7s I have in transit(these things have too many damn numbers) won't be up to the "standards" of all the other tubes I've gotten; I should delete this before I jinx my success rate)

That's funny, one tube I really like was bought from tubemongers by a PO of one of my amps.  I know it was theirs because the box has the tube name all over it and tubemonger on the label.  The tube is basically junk though :(  Sounds great for about 15 minutes and then it just sounds like a disaster.  I'm real scared to buy tubes these days; eBay seems like a major hit or miss and the markup at the online retailers hurts.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: The Alchemist on July 25, 2014, 02:13:38 AM
Hello fellow Pirates!

I need some help/advice. So I have a Valhalla 2 and the Valhalla 2's input tubes can be subbed out for any 6DJ8/6922/ECC88/ECC85/6BZ7 types, including NOS. Currently I am just using the stock standard 6N1P input tubes but was wondering if any of the other input tubes that the Valhalla 2 can be rolled with would be any better than the stock 6N1P's.

The Valhalla 2 sounds great with stock, but it doesn't seem to have the warmth of the original Valhalla. I like a warm, tube sound that fellow Pirates may think would sound better than the stock 6N1P input tubes.

Any Help or advice on which tubes my fellow Pirates would suggest would be extremely helpful. I believe only the input tubes are rollable.

Thanks!
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: The Alchemist on July 30, 2014, 03:30:02 PM
Hello fellow Pirates,

I was looking to get a pair of 6BZ7 matching tubes for my Valhalla 2 and I was looking on eBay and I am not sure what kind to get (I have never tube rolled before). Marv suggested checking out 6BZ7's so that is what I have been looking at. I don't know what brand I should get, if I should get matching tubes, or NOS. Can some fellow pirates give me some suggestions on tubes for the Valhalla 2? Should I get matching? NOS? What brand?

Thank you for any help and advice anyone can give!  :)p7
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Puma Cat on January 24, 2015, 09:06:50 PM
I've got a Valhalla 2 as of yesterday, and as you can sub in 6922s, there are lots of nice options for those tubes.

Two "classic" options are the orange-label Amperex, and the famous Amperex Bugle Boys. Another very nice 6922 is the Ediswan, which is available from Upscale Audio.

The newer released Genalex Gold Lion 6922s are excellent for the money, also.

I will probably end up with Ediswans in my Valhalla 2, though they are pricey at $95/ea.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Ringingears on January 28, 2015, 05:43:30 AM
Has anyone tried the NOS GE 6BZ7's from Schiit that they sell for the Lyr amp in a ..........Valhalla 2 ?  Better than the stock Russians? No difference or worse? Just wondering if the price was worth any improvements over stock. Saw a reference to Marv liking these tubes. Marv, could you clarify?

Jason: could you tell us the reason you use the NOS GE in the Lyr and the Russian type in Valhalla 2?  Thanks.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Puma Cat on February 01, 2015, 08:06:45 AM
I just rolled some vintage Amperex 6922s (Orange PQ label) into my Valhalla 2 and they essentially transformed the already excellent performance of this headphone amplifier for the better. See my post in the Valhalla 2 review thread for more information, but man, was this an improvement! I was thinking of rolling Ediswans into the Valhalla 2, but I just may stick with this tube; it takes the Val 2 to a completely different level.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: bmichels on February 13, 2015, 12:55:20 PM
hello here tube lovers

On my Eddie Curent 445 tube Amp, I would like to try to replace the 6C45 driver tubes by some WE417A.  this should mahe the sound signature more tubey, more warm.  the 6C45 is too analytical and too SS for my taste.


 I have been able to find the  WE417-to-6C45  adaptors   :-\     

--> So now I need to find a pair of NEW and matched WE417A driver tubes. ... and a new DAC ( TotalDAC D1 or Analog DAC...)

can someone help ? that are quite hard to find (in NEW and matched)

thanks in advance

(http://cdn.head-fi.org/2/20/900x900px-LL-20b0ebae_TransfoBlackcoverside.jpeg)
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: BleaK on April 18, 2015, 02:59:07 PM
Pretty good 6922 tube review:

http://www.head-fi.org/t/761078/6922-tube-review-17-top-6922-6n23p-e88cc-cca-7308-e188cc-tubes#post_11464856
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: The Alchemist on April 19, 2015, 04:09:39 AM
I just rolled some vintage Amperex 6922s (Orange PQ label) into my Valhalla 2 and they essentially transformed the already excellent performance of this headphone amplifier for the better. See my post in the Valhalla 2 review thread for more information, but man, was this an improvement! I was thinking of rolling Ediswans into the Valhalla 2, but I just may stick with this tube; it takes the Val 2 to a completely different level.

I have been using the V2 since it first came out and been using mostly the stock tubes. I bought a pair of cheap NOS GE 6BZ7's but didn't notice much of a difference in sound (using Bifrost Uber as DAC and HD650's for Headphones). A good friend of mine (thegunner) also has/is using Amperex 6922's tubes in his Valhalla 2 (Not sure if they are Orange PQ Label or not) and he seems to like them.

You stated in your post that the Amperex 6922s (Orange PQ label) really improves the Valhalla 2 and "...takes it to a completely different level". Can you explain in a little more detail in what you mean by that? I have never really done tube rolling before so I know virtually nothing about it, or what is good and what isn't. The only tubes other than stock that I have tried in my V2 are the NOS GE 6BZ7's, but as stated above, I really could not tell any difference in sound (at least to my ears).

What quality or improvement do the Amperex 6922s (Orange PQ label) do for the V2? Does it add warmth for example? If you could explain in a little more detail to a newbie like me I'd really appreciate it. Great post!
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Sorrodje on May 19, 2015, 12:20:06 PM
Does someone can help for 2A3 tubes and 5U4G ?

Juste grabbed a pair of very rare Miniwatt 2A3.. probably sylvania replica with specific french parts , made by Visseaux in 1948 But I would like to know if any other NOS options worth anything.  For New tubes,  I've read a lot of impressions of review and asked Donald North.. so I know what could be interesting for me but in NOS options, I struggle more so  any good advice would be appreiciated ;)

the amp will be the Stratus for a HD800.



For 5U4G ,  I bought a NOS RCA black plate , some french Neotron (RCA built in France . I will try JAN 5931 and maybe NOS Svetlana Black plate... I'm open to new ideas... not to 400 bucks ideas though.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: smitty1110 on May 19, 2015, 03:17:17 PM
Does someone can help for 2A3 tubes and 5U4G ?

Juste grabbed a pair of very rare Miniwatt 2A3.. probably sylvania replica with specific french parts , made by Visseaux in 1948 But I would like to know if any other NOS options worth anything.  For New tubes,  I've read a lot of impressions of review and asked Donald North.. so I know what could be interesting for me but in NOS options, I struggle more so  any good advice would be appreiciated ;)

the amp will be the Stratus for a HD800.



For 5U4G ,  I bought a NOS RCA black plate , some french Neotron (RCA built in France . I will try JAN 5931 and maybe NOS Svetlana Black plate... I'm open to new ideas... not to 400 bucks ideas though.
Seconding this, though my stratus doesn't arrive for a few months.
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: Sorrodje on May 19, 2015, 03:33:44 PM
Seconding this, though my stratus doesn't arrive for a few months.

For 5U4G, it seems the NOS Svetlana 5U4G are amongst the best . they're cheap and I'll oder a pair soon. Jan-CHS 5931 sylvania as well. cheap too ;) . 6BQ7A are cheap and easy to find so when the Status will arrive I'll have the oppotunity to test a bunch and choose the one I prefer. I Struggle a bit more to find for 2A3. I maybe found a NOS pair of RCA here in France but I don't know if they really worth something against new production. I haven't the price yet. 
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: jsgraha on May 19, 2015, 10:12:59 PM
I have 6bq7 from RCA and Westinghouse. I prefer RCA (slightly warmer) to Westinghouse. For some reason, Westinghouse offer wider stage, but not much depth. I prefer 6n1p variant to both 6bq7. I used to have pearl cryo 6n1p Reflektor from partconnexion. However, it develop noise after 2 years of use. So I order another one from partconnexion, and received one 6n1p-EV, but different brand from Voskhod. However, this tube was bright, so I decide to find one from ebay (not cryoed). I found the one that I like (similar to Cryo Reflektor) which was Gold 6N1P-VI. I remember paying around $18 for 4pcs.

For 5u4g, I only have experience from RCA 5u4g and GEC/Osram U52. U52 just much better that RCA 5u4g. I was lucky to have 2 u52 locally at my local forum in aus for quite cheap. U52 offer expansive stage and better bass texture to 5u4g RCA.

For 2a3, I would be interested to learn NOS tube. My experience so far only with new tubes from shuguang, sophia and full music. So far, I prefer mesh sophia (nice tone, big stage, great bass ext). 2A3-Z from shuguang is nice, but low bass extension is lacking (I read on hf, the 2a3-t one not much better than 2a3-z, but please correct me if I'm wrong). Full Music SE is nice as well, particularly in decay and texture, but losing to mesh sophia in staging. Stock 2a3 from Donald actually is really nice. I prefer it to 2a3-z with hd800. It's fun and raw presentation, kinda remind me of vali with better staging and bass
Title: Re: Tubes, Tubes, Tubes -- Resources for Rollers!
Post by: bixby on May 23, 2015, 11:14:29 PM
Just a quick note on 6sn7 tubes.  I spent a number of years acquiring used  classic 6sn7 tubes for an entry level headphone amp and for my deHavilland preamp.  A new TJ Full Music 6sn7 put a stop to all the comparisons and searching for reasonably priced old stock.

Really well balanced tube in my pre.

EDIT:

Well that was brief, less than 6 months and the tube is showing audible degradation.  hahaha, so much for new Chinese stuff keeping up with old used stuff.  I am now trying some nice brown bass military Tungs and Syls, nice and strong!