Tubes Asylum

Questions about tubes and gear that glows. FAQ

Return to Tubes Asylum

Message Sort: Post Order or Asylum Reverse Threaded

Least fatiguing 12AX7

174.234.1.110
Posted on May 10, 2024 at 19:27:39
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 Hi. I am looking for a list of the warmest, smoothest and least fatiguing 12AX7 or electrically compatible equivalents, with low noise types scoring even higher.

Special emphasis should be on tubes that are still affordable.

 

Hide full thread outline!
    ...
RE: Least fatiguing 12AX7, posted on May 11, 2024 at 07:08:25
dgaapc7
Audiophile

Posts: 431
Joined: August 16, 2013
 I found the Psvane 12ax7 to be very good. Apparently there are different versions of the tube and, unfortunately, I don't know which one I have. The tubes I do have are warm and holographic, very enjoyable. They are a bit on the polite side.
LowIQ

 

RE: Least fatiguing 12AX7, posted on May 11, 2024 at 07:35:03
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 I ended up buying a Hammond labeled GE long grey plate fat D getter 12ax7 (v2). I am combining it with a GE double mica support rod grey plate 5751 (v1, don't know what this one sounds like), and an RCA 6201 (v3).

 

RE: Least fatiguing 12AX7, posted on May 11, 2024 at 07:40:12
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 My EAR 834p clone came with red-label classic Psvanes. They are probably the best entry level Chinese made tube, but not smooth enough in the upper mids and lower treble with agressive recordings.

 

RE: Least fatiguing 12AX7, posted on May 11, 2024 at 07:41:13
Tre'
Industry Professional

Posts: 17554
Location: So. Cal.
Joined: February 9, 2002
 RCA long black plate 12ax7s but I don't think they are affordable anymore.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: Least fatiguing 12AX7, posted on May 11, 2024 at 08:33:34
Triode_Kingdom
Audiophile

Posts: 10181
Location: Central Texas
Joined: September 24, 2006
 If you have the option of rewiring the filament (or if this is for a DIY project), the Russian 6N1P-EV is very smooth and also affordable.

 

Mullard, posted on May 11, 2024 at 15:21:45
Jon L
Audiophile

Posts: 6154
Joined: April 6, 2000
 You can still find very strong Mullard ECC83/7025 for around $50-60 when they were labelled as Bogen, IEC, etc. I assume you want GREAT sound while being warm, smooth!

 

Or just bypass the plate resistor with 250 to 500pf cap to tone down the treble , posted on May 13, 2024 at 07:21:30
Chip647
Audiophile

Posts: 2693
Location: The South
Joined: December 24, 2012
 Most people really need tone controls as bright treble is the bane of a lot of speakers and also excites tinnitus

 

Wouldn't doing that increase HD?, posted on May 13, 2024 at 13:58:24
Tre'
Industry Professional

Posts: 17554
Location: So. Cal.
Joined: February 9, 2002
 I understand that it would decrease the HF but it would also decrease the load impedance the tube is seeing at those high frequencies and increase distortion produced by the tube. There has to be a better way.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: Wouldn't doing that increase HD?, posted on May 13, 2024 at 20:37:00
Triode_Kingdom
Audiophile

Posts: 10181
Location: Central Texas
Joined: September 24, 2006
 The effect will be minimal if only very high frequencies are affected. Step networks are common in a lot of gear. Difficult to know whether this is related to the OP's question though, because no one knows what the symptom actually is. Also difficult to know if a step network is appropriate without knowing anything about the circuit. Questions like the first post generally indicate a lack of understanding about tubes.



 

RE: Wouldn't doing that increase HD?, posted on May 14, 2024 at 07:32:51
Tre'
Industry Professional

Posts: 17554
Location: So. Cal.
Joined: February 9, 2002
 That's a little different.
In your example when C82 goes to zero ohms, the tube is still seeing 15k.

That would not be the case if he "just bypass[ed] the plate resistor with 250 to 500pf cap".

It's not a big deal, I was just pointing that out.

I've also seen phono preamps with "one shot" RIAA filters with impedances so low that the first stage won't stand a chance driving it. In the discussion that followed people were trying to tell me that that is how filters work....by "choking" the tube. :-)

I tried to explain that you can make R1 big enough so A1 (if it were a triode) is not being loaded down. I'm not sure how many understood.




All I'm saying is, you can use a filter to contour the frequency response without placing the tube driving that filter in distress.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

It boils down to the circuit having by far the biggest impact on sound, posted on May 14, 2024 at 08:51:06
Chip647
Audiophile

Posts: 2693
Location: The South
Joined: December 24, 2012
 of a component compared to tube flavor. People want/need +/- 3 to 6db and more impact on the frequency response when they are unhappy with the sound. If one brand of tube is "too bright", another brand will not produce a meaningful / measurable difference in frequency response unless one of the tubes is broken. The issue is typically boils down to the frequency response and impedance by frequency of the loudspeakers.

Many guitar amps use the cap across the plate load to smooth out the harsh icepick frequencies they can produce. I have played with bypass caps on the plate load resistors and the impact is pretty subtle in the 250pf range when listening. A shelving resistor, as pointed out, is best.

The reality is that people want and need tone controls but are too scared to have them because the cool kids say they are terrible.

 

agreed. nt, posted on May 14, 2024 at 08:58:06
Tre'
Industry Professional

Posts: 17554
Location: So. Cal.
Joined: February 9, 2002
 .
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: It boils down to the circuit having by far the biggest impact on sound, posted on May 19, 2024 at 03:32:14
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 The circuit in my EAR clone is a very neutral one. It clearly shows the different strengths and weaknesses of the tubes I have been rolling thru it.

Anyway, the GE 5751 is out of commission with a broken pin.

I have spent several days auditioning the tubes in different positions, and have found that it sounds the most balanced, warm and true with the stock red-label classic Psvane in V1, the GE 12AX7 in V2, and the RCA 6201 in V3.

 

RE: It boils down to the circuit having by far the biggest impact on sound, posted on May 19, 2024 at 12:38:09
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 I am going to have to dump the RCA do to it having too much emphasis on the edges of metallic objects.

 

RE: Least fatiguing 12AX7, posted on May 20, 2024 at 15:52:59
BCR
Audiophile

Posts: 2451
Location: connecticut
Joined: April 7, 2009
 Sylvania-Baldwin green label and GE are the two brands that I use. Both are reasonably priced!

 

RE: Least fatiguing 12AX7, posted on May 23, 2024 at 13:51:57
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 I am now running 2 indentical GE 12AX7's V2-V3 to good affect. I will be replacing the remaining stock tube when I find another matching GE.

 

RE: Least fatiguing 12AX7, posted on May 23, 2024 at 16:39:41
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 My initial findings on these GE's is that they are neutral and extended, but lack a little harmonic texture. They have good air, space and imaging with exceptional rendering of high frequencies.

What I would like to do now is to find a tube that will warm things up a bit, and provide fuller harmonic detail (Mullard?).

 

RE: Least fatiguing 12AX7, posted on May 24, 2024 at 01:01:15
Tarzan
Audiophile

Posts: 197
Location: UK, Essex
Joined: May 2, 2003
 The new JJ electronic e83cc are remarkably smooth and well balanced from top to bottom- nice price too, probably my favourite new production 12ax7.

 

RCA blackplate nt, posted on May 28, 2024 at 14:45:03
Tre'
Industry Professional

Posts: 17554
Location: So. Cal.
Joined: February 9, 2002
 .
Have Fun and Enjoy the Music
"Still Working the Problem"

 

"people want or need tone controls, absolutely... Sometimes must correct for Engineers or Charlie Parker , posted on June 1, 2024 at 13:21:49
Cleantimestream
Audiophile

Posts: 7579
Location: Kentucky
Joined: June 30, 2005
 !
The Mind has No Firewall~ U.S. Army War College.

 

RE: Least fatiguing 12AX7, posted on June 4, 2024 at 18:27:57
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 I have now found the ideal match by using the Hammond labeled GE in V1, the stock Psvane in V2, and a later GE short grey plate with round halo getter in V3.

The sound is now more neutral and balanced, with nothing added, subtracted or calling attention to itself, and has just the right amount of air, space, imaging and transparency to satisfy.

 

RE: Least fatiguing 12AX7, posted on June 5, 2024 at 08:13:57
DaveV
Audiophile

Posts: 518
Location: SC
Joined: December 26, 2009
 Changing parameters can alter sonics so there are many variables for sure.
The debate about rectifier tubes may be partly due to voltage drop characteristics changing the operating parameters.
Using a 5751 in place of a 12AX7 seems to be fairly common lately but why focus on tubes as if capacitors in use are the be all end all?
My experience has been with vintage equipment and I've found that changing capacitors can alter the sound from the moment you turn the piece of equipment on with no so called breakin and sometimes a $2 cap just sounds better than a $30 "audiophile" cap and it's far less expensive than chasing NOS tubes. Not that tubes don't make a difference but why be restricted to them.


.

 

RE: Least fatiguing 12AX7, posted on June 5, 2024 at 13:21:42
SoundMann
Audiophile

Posts: 633
Joined: October 21, 2015
 I have been thinking about adding a few oil caps in a couple of critical places.

 

RE: Least fatiguing 12AX7, posted on June 5, 2024 at 15:10:27
DaveV
Audiophile

Posts: 518
Location: SC
Joined: December 26, 2009
 Paper in oil caps may produce a warmer presentation but don't overlook NOS or new polyester film and foil capacitors.
Sometimes an under $2 Illinois Capacitor Polyester Cap seems just right and placement in the circuit can matter when you start changing caps.

 

RE: Least fatiguing 12AX7, posted on June 25, 2024 at 00:56:03
ivan_terrible
Industry Professional

Posts: 220
Location: Ivangorod
Joined: April 26, 2015
 I think this is all totally imaginary.

If you are really *nal about valves use 6EU7 and rewire it.

 

Page processed in 0.041 seconds.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]