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Doge 8 Clarity: 12AT7 replacement for phono stage

Hello fellow enthusiasts... My apologies in advance for the noob question.

I've put together my first all tube system, as far as preamp and amp combo is concerned. Looking to see IF replacing the phono section's 12AX7 (Mullard ECC81) tubes with lower gain 12AT7 in my Doge 8 Clarity 2017 ed. will help lower the "hiss"/ tube rush coming off with my current set up. Doge's phono setting is on MM (using Bob's Device Sky 20 SUT), Phono: 47k, tried both normal and low sensitivity, (- 8) gain reduction, but "hiss" is still audible from my seat 7' away from the speakers. 

I'm looking at replacement tubes from Upscale - Mullard 6201 which they claim to be the "quiet" ones. Not sure if it will help in lowering the hiss I've described.

Doge's line level still holds the stock 12AT7 tubes and to me - they sound nice as the reviews online says. I'm sure it can do better with tube rolling. No audible hiss from my seat. Switching between any line level onto phono input clearly augments the hiss.

To take advantage of Doge's much improved line level over the phono, I've utilized my only external phono stage - Schiit Mani. Not ideal but i can handle that better than deal with the hiss using the Doge's internal phono stage. I've contemplated on just upgrading to a nicer phono stage but that's another topic.

So, will it work to replace the 12AX7 with lower gain tubes 12AT7 to decrease hiss in my system? 

Thank you in advice for your time and responses.

Current system:
Rega P3 (2016), NEO ttpsu, DV 20X2L
Schiit Mani to line level vs Bob's Device Sky 20 to phono level
Doge 8 Clarity 2017 ed.
Mystere PA11 
KEF R3 on stands



oyie2000
Post removed 
bdp24's avatar
bdp24
9,412 posts
 
The Schitt Mani RIAA phono amp has a "Decca" gain setting, which provides 30dB.
robertplata
5 posts
 
Of all the tube gear in a system the phono stage/pre amp section is most susceptible to tube variances. If there is ONE place to splurge on tightly matched high quality tubes, this is it! I totally agree with what others have stated, buy from a known tube dealer. Inform them that these tubes you're buying will be used in a circuit, in a tube phono stage. Best of luck. 
oyie2000 OP
13 posts
 
I have to say, you all have been great in sharing your wisdom about this awesome hobby and passion we all share. I thought I've read enough about tubes but I obviously have yet to scratch the surface per se. The last 24 hours have been very informative. Thank you all!

@ bdp24: RAM Tube Works - definitely worth checking out. If it wasn't for work getting in the way ; ) - I would've made some headway in calling about the tube recommendations here.

@ lowrider57: the brief moment i got to check iPhono2 online - it appears to be a good contender for what i'm looking for. I'll have to do some more research, and see some comparison reading between that and the DV P75 which both are under $1k and falls under my budget in case I go that route.

@ jsautter: I was actually thinking of using 12AT7 instead of 12AX7 on the Doge's phono stage which requires the latter. I will contact Doge Audio to check whether it is even feasible what I'm trying to do, or better yet, see what they have to say.

oyie2000 OP
13 posts
 
@ atmasphere: I appreciate your input and guidance. I know you're well respected in these forums. I will do the test you recommended I do, and will report back.

@ mulveling:  Thank you for the valuable tips in increasing signal to noise. Looks like I will have to really look at a good set of quality, quiet, MC phono grade tubes compatible with my Doge 8 to properly achieve my goal. 

@ robertplata: Splurging! Yes, and as mentioned above, I will have to pony up for the "right" tubes. 

I'm glad I posted this question of mine, as I was ready to pull the trigger on some tubes that I would have not been able to return. That would've been an expensive experiment. 

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