TUBES(pre, power, rectifier) share your list of tubes

[jb77]

For all of the ‘Tube Heads’ out there, this is the place to share your list of tubes and what you think about them.

Below is my list of pre tubes, as I currently only have hybrid tube amps, the Schiit Mjolnir 2 and the Monolith Liquid Platinum.

Tube list:

6922 variants

1. Stock Electro Harmonix 6922
2. Stock 6BZ7 tubes for MJ2
3. Matsushita / National PCC88/7DJ8
4. Tungsram PCC88/7DJ8
5. Telefunken PCC88/7DJ8
6. Amperex 7308 vintage gold pin (green label JAN’s)
7. Brimar KB/AD CV2492 E88CC
8. Brimar E88CC Gold Pin UK Valve Tubes
9. Amperex Bugle-Boy 6DJ8/ECC88 D getter, date codes: Delta 8K, Delta 8L
10. 1950’s SYLVANIA - D getter 6922 gold pins (VERY RARE PER AC)
11. 1950s LORENZ STUTTGART - PCC88 Grey shield, 2 mica

12AU7 variants

1. Mullard Blackburn ECC82 long plate square getter UK B- factory code 56/57
2. Mullard Blackburn goal post getter ECC82
3. Brimar CV491/12AU7/ECC82 Long Plate Square Getter England 1958
4. Valvo 12AU7 ECC82 Germany, Hamburg Made Tubes (GfO D9E), SlantedGetters
5. Telefunken ECC82 Smooth Plates
6. Siemens ECC82 Silver Chrome Plates 12AU7
7. Amperex Holland long plate foil D getter 7316 / 12au7 1958 (Beckman label)
8. Amperex Holland long plate foil D getter 7316 / 12au7
9. Amperex PQ 7316 ECC186 12AU7 D Getter matching 461 codes
10. Amperex Philips ECC82 long plate foil D Getter 57/58 Heerlen Holland
11. Brimar ECC82 1970s HALO-DISC Getter Short Plate Mazda LABEL - Thorn-AEI - England
12. Tesla (NOT JJ) 1975-82 Military Long PL. ECC802S prem. 12AU7
13. RCA 12AU7 Black Plate Square getter 1957
14. RCA 12AU7A Clear Tops Conn label
15. CBS Hytron JHY 5814A/12au7 Black Plate, Bent rectangular Getter a8
16. Sylvania JHS 5814WA/12AU7 Military Triple Mica Black plates code 5639B 312J
17. Baldwin Raytheon 12AU7 long shiny black plates
18. Marconi MWT B329 ECC82 BRITISH MADE
19. BRIMAR CV4034 - 1970 Military Long Plate Prem. Grade Long Life Halo Getter STC Prod. ENGLAND
20. Amperex 12AU7 BugleBoy

12AT7 variants

1. Valvo Hamburg Pinched Waist 6201 double post O getter 1959
2. Valvo Hamburg Pinched Waist 6201 double post O getter 1959 blue label
3. GEC CV6091/A2900, 1964, Black Plates, D Getter 3x mica
4. GEC A2900 2x mica
5. Telefunken ECC801S
6. Marconi B309 12AT7 ECC81 Black Plate Ring getter
7. Brimar 6060/12AT7 Yellow T Tube Made in Britain E81CC 6201
8. Brimar CV4033 Military Black Plate Prem. Grade Long Life ECC81/CV4024/12AT7 Halo Getter STC Prod England 1960-62
9. Brimar 6060 CV4024 12AT7WA TRIPLE MICA
10. Mullard Blackburn ECC81 56/57 TK1 square getter
11. Mullard Mitcham ECC81 1956 square getter
12. Brimar ECC81 1954 square getter
13. Heerlen E180CC/7062 1957 PW
14. Siemens & Halske E81CC - 1960s 3-MICA 6201 Munich W. German Prem. ECC81 12AT7
15. Valvo 1967 E81CC 6201 12AT7WA Gold Pin ADZAM SQ SPECIAL QUALITY Label - Hamburg Germany

12AX7 variants

1. RFT ECC83/12AX7
2. Tungsram ECC83 12AX7 - MINT NOS NIB RARE Sept 1962 Welded Plate Tubes - Hungary

Other variants

1. *Telefunken 6211 [LP]
   (very close to specs of a 12AU7)
2. TESLA 6CC41 (6N2P ~ECC83) 1958 Silver Plate lk. Mazda/Cifte,D Getter
   (6922 pin layout, however specs close to that of a 12AX7)

WE396A/6N3P/2C51 etc. variants

1. WE396A 58’s
2. Foton 6N3P 58/59’s
3. Foton 6N3P 59’s
4. Reflektor 6N3P 50’s era
5. LM Ericsson 2C51 steel pin square getter
6. Marconi 5670 2C51 Tubes Red label Square/Rectangular Getters
7. Marconi 5670 2C51 Tubes White label Square/Rectangular Getters
   
   
   
   
   

[jb77]

@Torq

Hi Ian,

Definitely interested in the tubes you have used

[metal571]

I only use genuine Mesa Boogie 12AX7s and 6L6GCs

[raindownthunda]

Wow @jb77, that’s an impressive collection! What are you favorite 12au7’s?

[jb77]

Thank You @raindownthunda

Once the ‘tube bug’ bit it bit hard as I purchased all of these tubes last year, once I got my first hybrid amp.

For 12AU7 my top 5 favorites are:

1. Brimar ECC82 1970s HALO-DISC Getter Short Plate Mazda LABEL - Thorn-AEI - England

2. BRIMAR CV4034 - 1970 Military Long Plate Prem. Grade Long Life Halo Getter STC Prod. ENGLAND

3. Mullard Blackburn ECC82 long plate square getter UK B- factory code 56/57

4. Amperex Holland long plate foil D getter 7316 / 12au7 1958 (Beckman label)

5. Tesla (NOT JJ) 1975-82 Military Long PL. ECC802S prem. 12AU7

Three of these can be easily found from a reputable company called Tubemonger

If you have any other questions just ask. And I’ll answer as best as I am able too

[jb77]

@metal571

I only use genuine Mesa Boogie 12AX7s and 6L6GCs

Nice!

I have not expanded much into 12AX7s yet, just two pairs to try so far.
Though I do enjoy my Tungsram ECC83 12AX7 - Sept 1962 Welded Plate Tubes - Hungary

[JonL]

I’ll share my recent tube-rolling notes in Elekit TU-8600R SET amp.
FYI. My preferences are for tubes that are very clear, neutral like good solid state, YET imparting just enough of the even harmonic tube magic without getting muddy.

(12AX7 ECC83 7025)

Full music 12AX7

Gold Lion 12AX7

Full Music lots of air but bit more whitish c/w Gold Lion 12AX7, which is less whitish and more focused/solid in upper mids still breathy/wet enough but is bit darker/denser.

Full Music likely has more defined slam in bass

Sylvania 12AX7 (" Baldwin ")

much more detailed in male voice (Leonard Cohen) than Gold Lion. Bass also less fluffy/diffuse.

Sylvania still has more balance, more inner detail in male (Cohen) and female without sounding whitish. Great defined slam and bass extension.

Sylvania 7025 (12AX7)

looks same as Baldwin above. Sounds about same, considering different age of tubes. Perhaps slightly larger/forward vocals?

Ei 12AX7

kind of sounds like PSVANE 12AU7. Images larger and less dense. Pretty airy and harmonic. less resolution than Sylvania 12AX7

Ei 12AX7 Silver plate

less full more resolution than Ei regular 12AX7 or Full music 12AX7, which sounds even more air-infused

CBS 7025 (12AX7)

Very rich, large, forward midrange, not as bright upper mids as Ei or Silvania. Bass not as impactful

Toshiba 12AX7A

Very clean, sparkling sound, much more present upper midrange, less grand than CBS 7025. lower midrange not rich (Cohen). great bass slam.

Matsushita 12AX7 (looks similar to Toshiba)

very clean, sparkling with clear upper mids like Toshiba but larger, richer midrange weight

Mazda 12AX7A Silver plate

very airy, whitish top, fast, even more so than Toshiba 12AX7, kind of like silver cable. But male vocals still middling rich ! (Cohen) Good bass denition/slam.

very lively, bright, exciting, sparkly sound.

Allegro 12AX7B

larger images but still pretty dense, not fluffy. More detailed version of CBS 7025? Not focused/dense. Great bass quality, quanity and extension.

Sylvania still has more balance, more inner detail.

Siemens ECC83 1961

compared to Sylvania, not as bright and slightly drier but still detailed in that German way. Full, forward tone.

Mullard 12AX7 (“IEC”)

Well known Mullard tone present. Kind of like Valvo ECC83, the classic tube tone but not quite as resolving as some others.

Valvo ECC83

although from same country as Siemens, Valvo’s tend to be mellower, richer, tubier. Same here.

Amperex 12AX7

familiar Amperex Holland house sound, similar to Amperex 7316 types. Midrange just richer of neutral with top-end just sparklier of neutral. Lovely.

(12AU7 ECC82 5814 6211)

Siemens 5814A triple mica 1962

Gold Lion 12AU7

Siemens 5814A very solid, controlled density and detailed but not bloomy/wet/breathy compared to Gold Lion 12AU7 , which is more fluffy/airy, less dense sounding

PSVANE 12AU7

slightly less resolution than Gold Lion. Images larger and less dense. Pretty airy and harmonic.

RCA 12AU7

smoother, creamier upper mids than PSVANE. denser, more controlled bass, too.

Male (Cohen) not as detailed but creamier than Gold Lion.

RCA 6211 1969

compared to Gold Lion, brighter and airier with strong upper bass. Big, forward vocals. Not ultra-detailed in vocal texture, but similar level as Gold Lion?

RCA 6211 black plate 1950’s

slightly more “vintage” sounding than 1960’s RCA 6211 but very similar. Bit less bright also.

Sylvania 6211 grey plate

Even brighter and faster sounding than RCA 6211’s, probably too tilted up for most systems unless system is too dark.

GE 6211 5-star 1962

Similar to other GE “5-star” tube types in sound. Bold, strong, forward but lacking topmost air and bit brash sounding.

Sylvania Gold Brand 5814 triple mica

Somewhat of “gold standard” in 5814 land. Less dry than the rare Siemens 5814A triple mica but also bit less dense. Very airy and smooth with good resolution. Can be too ethereal in some applications compared to more forward-sounding brands of 12AU7.

Sylvania grey plate 5814 triple mica

Kind of like this Sylvania better than the Gold Brand due to bit more air, sparkle. Grey plate bit less creamy.

Prefer both Sylvania 5814 types to RCA 5814 and Raytheon 5814

Amperex 7316 D-getter

That great, rich Holland tone while not sacrificing top-end sparkle that some Mullards do.

Mullard CV4003

Inimitable Mullard tone and richness. Not for lovers of Siemens type of microdetails.

Valvo 6067 (12AU7)

BIG TONE and timbre king. Quintessential tube sound, but not as modern sounding in resolution.

[jb77]

Nice collection! @JonL
Thank you for sharing

[raindownthunda]

Here are the tubes I’m using for my Bottlehead Crack. I’m also collecting 6j5/12j5, C3G, and 6bx7 tubes for my upcoming Glenn OTL but will exclude those for now since I can’t claim I’ve heard them yet :

Power tubes

• 4x Chatham 6080wb solid graphite
• 3x Bendix 6080wb slotted
• 1x Chatham 2399 (T.S. 5998 rebrand)
• 4x Tung-Sol 5998
• 4x Western Electric 421A
• Tung-Sol 7236
• Sylvania 5998A
• GE 5998A
• RCA 6080

Driver tubes

• 2x Amperex 7316 long plate foil D getter
• Brimar 13D5
• Brimar CV4003
• 2x Sylvania 5814A triple mica square getter
• RCA 12au7
• GE 12au7
• Mullard ECC82

[jb77]

Nice collection @raindownthunda, if you have a chance once you get the Glenn OTL let me know how you like it.

[jb77]

Thank you

Yea last I heard I believe it is around the 6-8 month mark to get the amp, I have heard a lot of good things about his amps and have been curious about them for a while now. And yes Glenn is a “maestro” in his work!

[ProfFalkin]

I have a drawer full of tubes. They go in my amps. I’m not posting a list. I’m too lazy and busy listening to music.

I will say the 12AU7 Mullard longplates, square getter, 1950s era tubes I got from Brent Jessee are my best for the Crack. I’ve inherited a Holy Grail input tube for my ZDS although all I know is it has a red base and sounds freaking amazing.

Hope that’s helpful in some way.

[FLTWS]

I’ve kept a data base forever so no problem to list. My tube chasing days are behind me. I’ve got more than I can ever use of each type before my time is up. And, when it comes to tube versus SS versus hybrid designs I embrace all. It’s not about the tech for me but about the sound. I heard / owned good and bad examples of each over the past 5 decades.

TUBE INVENTORY & TYPE - 6922 / 6DJ8 / 7DJ8 /7308 / PCC88
2 EACH matched pairs required for MJ-2
MY OLD NOS STOCK (purchased during 1980’s and 1990’s all NOS except*)
2 Yugoslavia 6DJ8 Plain White Boxes*
2 Yugoslavia 6DJ8 Branded “RAM” Graded “SA”*
2 Gold Aero 7308 / E188CC Platinum Series SN’s 1046 & 1047
1 Gold Aero 6DJ8 / ECC88 (#8320PH) (Made in Hungary) – SN 1110
1 Gold Aero 6DJ8 USA - JAN 6DJ8 - Philips ECG -34167USA – SN 1048
MY NEW NOS STOCK (Matched Pairs)
2 TUBEMONGER - Brimar Ediswan ECC88 1960’s
2 x 2 M/P iFi GE JAN 5670W Made in USA
UPSCALE AUDIO NOS
2 Amperex Jan 7308 Green
2 Telefunken ECC88 / 6922
2 Telefunken PCC88 / 7DJ8
2 Siemens A - Frame E88CC / 6922
2 Pope PCC88 / (Made in Holland): (Pope is NLA)
2 Tungsram E88CC / 6922
TUBE INVENTORY & TYPE: 12AU7 / CV4003 / ECC82 / M8136
2 EACH for RH-5 and Matched Pairs
Tesla JJ 12AU7 are the stock tube for RH-5 and they are good.
UPSCALE AUDIO
2 Mullard M8136/CV4003
2 Amperex Medical 12AU7
2 x 2 Brimar CV4003
2 Radiotechnique 12AU7WAH
2 Gold Lion ECC82/B749
2 Cifte 12AU7
(Note: can also be use in Valhalla 2 with adapters)
TUBE INVENTORY & TYPE: 6SN7 /
1 EACH for LYR-3
UPSCALE AUDIO
Sylvania Black Plate 6SN7WGTA
CBS Hytron 5692 / 6SN7
Early Russian 6H8C / 6SN7
BRENT JESSE
Tung-Sol 6SN7GTB New Production 17 09 (Stock LYR-3 tube) light brown base, black parallel plates
Tung Sol Military Grade JAN 6SN7WGTB: brown base, with black triangular plates
Sylvania Military Grade JAN 6SN7WGT/A: USA Early type, brown base with black triangular plates
Sylvania 6SN7GT - VT-231 JAN, black plate, clear glass, bottom getter, medium glass envelope
Raytheon 6SN7GT, black plate, clear glass with yellow or orange label, medium glass envelope
KEN-RAD 6SN7GT –VT-231, JAN-CKR, staggered black plates, black glass, SC961A (1 single and 1 matched pair)
RCA 6SN7GTB, USA 56 52, staggered black plates, side getter, 1956 short clear bottle
RCA 6SN7GT, USA 213, grey / black glass, staggered black plates, 1952
WESTINGHOUSE 6SN7GTB, “Halo” getter, tall bottle, staggered flat plates
WESTINGHOUSE 6SN7GTB, Reliatron, “D” getter, medium bottle, USA 337 USA 7R43
WESTINGHOUSE 6SN7GTB, Reliatron, “D” getter, medium bottle, (backup)
WESTINGHOUSE 6SN7GT, staggered plates, bottom getter (?)
BALDWIN ORGAN 6SN7GTB, medium bottle, round micas, “Halo” getter, “matched pair”, these apparently made for Baldwin by Sylvania. (Westinghouse also made this tube for Baldwin as well.)
TubeStore
JJ Electronic 6SN7, New Production, matched pair.
El Raydor (eBay source)
FOTON (x4) 6N8S (6SN7 / ECC32 / 1578). FOTON NOS TUBES, 1953 (Two matched pairs)
Grant Fidelity/Psvane
PSVANE 6SN7-UK vacuum tubes (low noise + dual sec matching, GF Select, pair)
PSVANE CV 181 TII vacuum tubes (low noise + dual sec matching, GF Select, pair)
Grant Fidelity / Shuguang Treasure
Treasure Globe 6SN7-SE / GF Limited Special Edition / A Grade / Single
Sophia Electric
6SN7 (New version), Grade “A” (top 10%), 1 year warranty / Single
Begrant-ru (Grant Berkovskiy)
1578 x 2 (6N8S, 6SN7) double triode, USSR, OTK, MELZ, One date 05.1986
From a Friend
7N7/S: “Frankentube” with 7N7 to 6SN7 adapter /PHILCO, Loctal, Made in the USA, 260/4952
Lowtechelec
1 RCA 6J5 / 1 Sylvania 6J5: Matched pair (per seller), metal can, single triodes (use adapter)
Viva Tubes
2 Raytheon 6J5: Matched Pair, glass tube, single triodes (use adapter)
TUBE INVENTORY & TYPE: ECC88/6N1P/6922/6DJ8/6BZ7 (see also my Upscale inventory on page 1 and 2)
Matched Pair for Valhalla 2 - May need adapter depending on type
STOCK TUBE: (Brand - ?) ARE RUSSIAN ORIGIN BUT NOT NAMED
Valvo / Philips 6201: 1961, matched pair across all 4 triodes for GM and plate current, source David Holmes of Ca. (Will require adapter 12AU/12AX to ECC88, 6922, 6DJ8)
Mullard 6201 (gold pin (?) version of the CV4024): from Upscale Audio (Will require adapter 12AU/12AX to ECC88, 6922, 6DJ8) Pins aren’t gold plated?
JJ Electronic ECC802 S (Long Plate version of 12AU7) Gold Pin: from Antique Electronic Supply (Will require adapter 12AU/12AX to ECC88, 6922, 6DJ8)
2 Russian 6H6P-I “Power Tubes” (OTK 12/84 6H6 I\I: Matched Pair, from Yen Audio (Direct Replacement)
TUBE INVENTORY FOR PRIMALUNA EVO400
PrimaLuna 12AU7 x 6 PrimaLuna EL-34 x 8 Gold Lion ECC82 / 12AU7 x 6 Gold Lion ECC82/B749 x 6 Gold Lion KT77/EL34 x 8 Gold Lion KT88 x 8

[Torq]

I can do the tubes I have for my primary amplifier from memory, the rest (which would be the rarer tubes I kept around after selling the amplifiers that used them) will have to wait until I am at home with my catalog.

My primary amplifier is a Woo WA234 MKII Mono, which can take 300B, 2A3 and 45 series tubes.

I have three “groups” of tubes I use with that, depending on what I am doing.

Most of the time I have Takatsuki 300B power tubes and 274B rectifiers in it. They’re replaceable fairly readily, and have excellent performance/sound, so those are my “every day” tubes.

I have a couple of sets of original NOS WE300B tubes that I swap in when I am likely to be doing more critical listening, or longer sessions of undistracted listening for pleasure. I have NOS WE274B to go with those, as well, though I’ve been leaning more towards the Takatsuki’s for that role lately.

And then I have some basic Sophia Electric Princess punched-plate 300B/274Bs that go in when I am taking pictures of the thing, as they have the best, brightest, most visible glow this side of the bigger thoriated tubes.

For 2A3’s I have a pair of original RCA mono-plates and another set of RCA black plates.

And then several sets of NOS RCA and GE 13EM7 (15EA7) signal tubes.

I’d say 90% of my listening is done using the various 300B options I have.

[Xgatt]

Where’s @Monsterzero at? This is your topic

[JonL]

@Torq

which can take 300B, 2A3 and 45 series tubes

The skyrocketing costs of 45/2A3/300B (and 6SN7) tubes are what drove me away from tubed equipment. Lucky for us, solid state and class D has come a very long way

[Torq]

I suppose it’s a matter of personal perspective.

I’ve spent more on tires for an afternoon at the track, a tank of fuel for the boat, or even on a bottle of wine (that lasted maybe 30 minutes), than any set of tubes big vintage power tubes I’ve bought and those last 10,000+ hours (potentially 30,000 with the NOS WE300B).

I have solid state amp options as well.

I see no reason to do anything class D when it comes to headphones though.

Actually, absent it being clearly audibly better in a blind listening test (which is always how I choose my speaker-system components) I don’t see a reason to do it in my speaker rig either.

[Monsterzero]

Thanks for tagging me as I wasnt aware of this thread…

Tubes…wow where to begin? My DAC takes tubes. My Glenn takes tubes. My speaker amp takes tubes.

I made this observation in Glenn thread some time ago,but it bears repeating. Tube rolling is a lot like cooking free-hand( a personal hobby of mine) Toss in some of this,a little of that and see how it sounds/tastes. Some tubes on initial listening are nothing special and get dumped back into the tube cupboard where they sit,ignored for ages until you find a combo of other tubes that make the forgotten tube sound like a million bucks.

I have too many tubes to list,though not as many as some others here. I also will be selling off most or all of my 6/12sn7 tubes. Drop me a PM if youre interested.
Sending my GOTL back to Glenn for some surgery and switching the drivers away from the SN7 types to another tube type which will remain un mentioned to keep the prices low,though theyre already rising. Damn tube dealers read these threads and hike their prices.

Oh,if anyone has a good pair of Tung Sol 7802s they’d be willing to part with let me know. Im also on the hunt for a pair of GEC KT66s smoked glass,and a Western Electric 422a that doesnt require me to sell a kidney. Again,PM me if you have some to sell.

[JonL]

@Torq

I see no reason to do anything class D when it comes to headphones though.

Actually, absent it being clearly audibly better in a blind listening test (which is always how I choose my speaker-system components) I don’t see a reason to do it in my speaker rig either.

True regarding headphone amps, except for the fact those of us speaker audiophiles keep wanting to connect our inefficient headphones (Abyss, hopefully RAAL soon) to our pre-existing speaker amps.
Good class D can also sound very nice driving electrostats via transformer, so another headphone role.

Most(?) class D amps simply have not sounded very good historically, but I must say the very recent class D stuff, especially ICEedge, have changed my mind about them. Here’s my ICEedge 1200AS2 based amp which is taking turns with my Elekit 300B SET, so who would have thought?

ICEedge 1200AS2 by drjlo2, on Flickr

[JTS]

Great thread! I just did a bunch of horse trading over the holidays. One of the things I picked up is an upgraded Mapletree Audio Design EAR+ HD. I purchased it from a good fellow who curated a nice collection of dual triode tubes. This amp uses 12B4A tubes in the follower stage and a single dual triode tube in the gain/driver stage.

I am still working my way through them but thought to add my list to this thread. I have a few notes on them here:

1. ECC83/12AX7 Mullard long grey plate. Warm, detailed, spacious. It’s a beauty listen, but it is not the most exciting tube of the bunch.

2. ECC81/12AT7 Amperex Bugle Boy grey plates, square getter. This tube is dynamic, smooth and fun to listen to. The bass is full, controlled and has a satisfying slam to it. The treble is clean, and sweet without a hint of fatigue.

3. 5751 Sylvania 3 mica black plate. This was my favourite for while. It is very dynamic, the bass is exciting, the treble is extended but not at all tiring and the imaging is compelling.

4. 12AU7 RCA cleartop. This tube sounds very realistic, detailed and clean. It is on the mellow/gentle side of things.

5. ECC83/B759 Genalex Gold Lion. I find this tube a bit sharp in the treble region. The bass, however, is also very pronounced. The staging is quite flat on this tube.

6. 12AX7LPSLPS Sovtek. This tube is surprising. The staging and imaging with this tube are quite good - everything is out front and in it’s own space. I find it a touch on the bright side. The bass is tight and impressive. It is more dry than the other tubes here.

7. 12AX7 Baldwin lens plate (organ tube). I am not certain which manufacturer made this tube - It is very cohesive sounding.The bass is very tuneful and controlled but less full than the Amperex or the Sylvania. The staging is less expansive than other tubes, but it makes up for it with it’s overall charming sound.

8. 5751 GE 5 star horseshoe getter. This tube is very detailed. The midrange is forward and the bass is tight but a bit lighter than other tubes. Treble is more pronounced than other tubes, but pleasant. The staging and imaging are very good. Timbre is noticeably realistic with this tube.

9. 12AT7WA GE triple mica grey plate Pearl Cryo. It’s light and tight on the bass. It’s a bit grainy in the treble. Staging is a bit “3 blob”.

10. Brimar 6060 Yellow T. Holy effing bass and space. The mids are smooooth with a great sense of presence. Staging is great and well outside my head. Might be my favourite so far.

I am developing a theory about this amp - it would appear to me that my tube preferences move towards the ones with a lower amplification factor: 5751, 12AT7, and even the 12au7 sound better to my sensibilities than the 12ax7. I notice principally in staging, imaging, and timbre. There is less slamming bass with these tubes, but I prefer them.

I asked Lloyd Peppard, who is the designer and maker of the Ear+ HD about what kinds of gain tubes I might be able to use, he responded, " You can of course try any dual triode with the same pinout (e.g. 12AU7, 12AT7, 12AY7, etc.). Just make sure they have the same heater current (0.15mA). Some (e.g. 12AU7 and 12AY7) have a lower gain factor (mu) so may not work as well in terms of overall gain and distortion."

I certainly have a winter worth of listening to do with the tubes I have on hand here, but at some point I will want to investigate others.

Anyone out there with a Mapletree Audio amp? What tubes are you listening to?

I am listening to the Ear+ HD with HD650M(SBAF kiss mod), HD600s, and a custom grado-style build with the Elleven Acoustica R1 drivers. My source is an RME ADI-2 DAC fs. I have the Monoprice THX887 that I use for work and reference. When listening for fun, I often upres redbook to DSD using HQPlayer (256/polysinc-xtr-lp/adsm7ec).