rabski

EAR834 tube rolling

Recommended Posts

Moderator

No problem Paul. I'm only in Kettering, so you're welcome to pop over any time and compare!

Share this post


Link to post
Share on other sites

Hi rabski,

I am very sorry to ask again, it finished a long time ago.

I also bought a new Ear 834P Deluxe, I search from a lot of forums to find the way to change its default tubes. I found out that I should change the V1 by 12au7 and keep 12ax7 for V2, V3. Now I am using 3 of Telefunken 12ax7s smooth plate (named The Fisher) and I can feel the sound is better than the original tubes. But I think the Ear could be better and better, so at the end please tell me some advices for my phono.

Thank you so much!

tungh

P/s: I am using Micro Seiki BL91, Micro MA505 mk3 tonearm, Ortofon MC30 Super Mk2 and the Hashimoto HM7 step-up. My amp is Gryphon Callisto 2100 and the speaker is Marten Duke mk1.

Share this post


Link to post
Share on other sites
Moderator

@rabski, any words of wisdom for the guy above? Old thread I know but you do know the hardware.

Edited by Cable Monkey
  • Upvote 1

Share this post


Link to post
Share on other sites
52 minutes ago, Cable Monkey said:

@rabski, any words of wisdom for the guy above? Old thread I know but you do know the hardware.

Thanks Mod! I am still waiting for some advices!

Share this post


Link to post
Share on other sites
Guest

There's a chap called biker boy (Doug) on here that also has experience with tubes for the 834P, might be worth dropping him a PM as he doesn't post much.

Edited by Guest

Share this post


Link to post
Share on other sites
2 hours ago, freefallrob said:

There's a chap called biker boy (Doug) on here that also has experience with tubes for the 834P, might be worth dropping him a PM as he doesn't post much.

Thank you and please give me the link. I am a new member here so I am trying to learn the direction of this forum.

Share this post


Link to post
Share on other sites

Hi there is a whole industry of diy mods to this fine phono stage. There are other tubes that can work well. Unless you have serious diy skills some of the mods are very extensive and I would urge extreme caution fiddling with the innards beyond swoping tubes

search for Rommy the Cat his site has loads of great info 

  • Upvote 1

Share this post


Link to post
Share on other sites
Super Wammer
On 22/02/2017 at 07:25, tungh said:

Hi rabski,

I am very sorry to ask again, it finished a long time ago.

I also bought a new Ear 834P Deluxe, I search from a lot of forums to find the way to change its default tubes. I found out that I should change the V1 by 12au7 and keep 12ax7 for V2, V3. Now I am using 3 of Telefunken 12ax7s smooth plate (named The Fisher) and I can feel the sound is better than the original tubes. But I think the Ear could be better and better, so at the end please tell me some advices for my phono.

Thank you so much!

tungh

P/s: I am using Micro Seiki BL91, Micro MA505 mk3 tonearm, Ortofon MC30 Super Mk2 and the Hashimoto HM7 step-up. My amp is Gryphon Callisto 2100 and the speaker is Marten Duke mk1.

Hi  tungh

I have this stage (mine is MM/MC although I only use MM as I have a lovely SUT).

Wait for Richard as I chatted to him when I bought mine, my front valve is RCA 5963 (that I had in stock) and the back is 5751 JJ Gold pin (on advice from Rabski)

5751 reduces gain but I still need an attenuator to stop it overloading my pre

FWIW, Paul

  • Upvote 1

Share this post


Link to post
Share on other sites
6 hours ago, Maverick said:

Hi  tungh

I have this stage (mine is MM/MC although I only use MM as I have a lovely SUT).

Wait for Richard as I chatted to him when I bought mine, my front valve is RCA 5963 (that I had in stock) and the back is 5751 JJ Gold pin (on advice from Rabski)

5751 reduces gain but I still need an attenuator to stop it overloading my pre

FWIW, Paul

Dear Paul,

Thank you for your information! So you meant the 5963 (12au7) should be in V3, and 5751 (12ax7) in V1, is it right? And how about the V2?

I agreed with you the gain is overloading with some pre. When I use my Ortofon MC30-W and the gain is out of control.

tungh

Edited by tungh

Share this post


Link to post
Share on other sites

I found a 6211 tube on the local store, I searched for the information and some results said that was the 12au7, but some said was the 12at7.

Did you have any experiences about this tube? Please give me an advice!

Thanks so much!

tungh

Share this post


Link to post
Share on other sites
Super Wammer
8 hours ago, tungh said:

Dear Paul,

Thank you for your information! So you meant the 5963 (12au7) should be in V3, and 5751 (12ax7) in V1, is it right? And how about the V2?

I agreed with you the gain is overloading with some pre. When I use my Ortofon MC30-W and the gain is out of control.

tungh

V2 should be left as is otherwise RIAA goes out of spec, to be honest I can't remember whether the one near the front panel is V1 and I'm away from home so can't check, send a PM to rabski as he's the expert around this parish

8 hours ago, tungh said:

I found a 6211 tube on the local store, I searched for the information and some results said that was the 12au7, but some said was the 12at7.

Did you have any experiences about this tube? Please give me an advice!

Thanks so much!

tungh

this is a useful table posted on here a couple of years ago, 6211 is not listed : 

12au7_tube_table.png

Edited by Maverick
  • Upvote 1

Share this post


Link to post
Share on other sites

Although I don't own an EAR I would recommend using a lower gain, low microphonics 6072A in place of the 12AX7 

Edited by mr.me
  • Upvote 1

Share this post


Link to post
Share on other sites
Super Wammer

Share this post


Link to post
Share on other sites
4 hours ago, Maverick said:

V2 should be left as is otherwise RIAA goes out of spec, to be honest I can't remember whether the one near the front panel is V1 and I'm away from home so can't check, send a PM to rabski as he's the expert around this parish

this is a useful table posted on here a couple of years ago, 6211 is not listed : 

12au7_tube_table.png

Some ebay sellers called 12au7. I think it is not common, but let try and hope it will working correctly.

Thanks for your guide!

tungh

p/s: Please see the picture and link from ebay

http://m.ebay.com/itm/1-x-Telefunken-NOS-ECC802S-6211-12AU7-ECC82-Test-GOOD-Diamond-Vacuum-Tube-/201797259736?hash=item2efc0dd1d8%3Ag%3AD1sAAOSwNnRYi-d5&_trkparms=pageci%3A60720c0c-fdba-11e6-95f3-74dbd180df6d%7Cparentrq%3A84ec42a715a0a7870bc18341ffe71750%7Ciid%3A7

IMG_4543.PNG

4 hours ago, mr.me said:

Although I don't own an EAR I would recommend using a lower gain, low microphonics 6072A in place of the 12AX7 

Thank you sir, 

I will find and try to roll the 6072A!

1 hour ago, Maverick said:

Thanks a lot!

I am reading and confirm ASPS!

Share this post


Link to post
Share on other sites
Super Wammer

not sure on your country but try Watford Valves site

  • Upvote 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.