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Tubes for your K&K Maxxed Out Phono?

Hi guys:

I took possesion of a new, full on preamp from Kevin about a week ago. I've been running LPs through it non-stop, maybe 15 hours so far.

I wonder about break-in aspects & do understand that this puppy needs a good amount of time, before those big Cardas parafeed caps open up in particular. That said, it is already capable of fantastic resolution & imparts some nice speed to my system in almost all tube rolling configurations. It's an awesome piece of kit, I can tell that already. Mine also has the 1931 trafos.. so a maxxed out, Maxxed Out, if you will. :)

My other gear is what i'd say is pretty neutral, with a "bouncy" front end: Art Audio HC Jota (AVVT 325Bs), Gill Audio Alana preamp, an OMA Lenco/Schick arm, with a SS retipped Denon 103R.

My issue is this: I just tried rolling some Siemens ECC88s in both the K&K and then I shifted them to my Linestage (I put some 60's Mullards in to the phono stage in their place). I'm surprised that even with some late 60's short plate Mullards in the K&K and the German tubes in the linestage. While the pacing is fantastic, it just seems a bit to hot for my ears.

It was even quicker & a little preferable overall with Valvos in my linestage & the Siemens in the K&K. I've gone through my cart setup a few times, i'm sure it could be better, but i detect no mistracking and my cart orientation (VTA/RTA) is just barely tail down.

I wonder if these Siemens are just a little "too much of a good thing" in the high end department for use with the K&K due to it being so nicely extended to begin with? May I ask what other Maxxed Out owners use in their preamps?

I'll fiddle with my cartridge a touch more before giving up on the Siemens entirely for phono stage duty. Maybe I should wait for some more run in time on the unit before drawing any such conclusions on valves? It is only a few hours into service.

I can eventually figure something out and roll some other types of tubes in to it; thinking something in the Amperex school now. Just a bit of a buzzkill, cause I love the pace the Siemens give everything. They really make an all tubed, glorified, high current 300b based SET amp system get up & boogie. Fatiguing if fatuiging though.

I didn't pay a ton for the valves.. by all identifers I can see, they seem like the real article, A3 issue Siemens E88CCs from the mid 60's. I thought they'd be detailed but a little sweet as per what i'd heard about them. I guess it's system dependent & semantics (like everything else).

My speakers are Ars Aures F1 floorstanders btw. Nice, musical & err on the sweet side. Not insanely detailed by reputation or in my room.

Thanks for any & all insights Maxxed Out owners. I've had some magic already with this unit & it ain't going anywhere. I'm just looking for that little extra, perceived pace, without the ear bleeding.

Regards, Marc
128x128marchomeslice
marchomeslice's avatar
marchomeslice OP
13 posts
 
Funny, my cartridge only outputs at .25 mVs (Denon 103r, sorry if I mentioned that already).

Kevin factory sets the unit at high output for the MC section which is appropriate to the 103r, but has the gain switches at their lower setting for the preamp as a whole.

I'm home now listening.. and I just switched the preamp's overall gain to the high setting. Which to me, is a little high, so I think I need to find out how to turn those pots down a touch.

Might be a stretch, but I also think this may be why those Siemens tubes sounded so hot. There was likely, a little too much gain compensation I was applying, through my linestage. Like a Valvo/Siemens double team. :)

So while i'm probably oversimplifying this.. but the Mullards I currently have in the K&K, sound more "like Mullards" now. A little less airy overall and more thick than they sounded with the K&K set to the low setting.

I have the current manual for the Maxxed Out Phono, but I don't think it has where to adjust those little biasing pots in it. I'll check again.. i'm almost positive that would help. Otherwise, I preferred it the way it worked in the low setting for the preamp. The way it is with both MC & the pre set both to high.. I have very little control with my linestage attenuators. It's a little too much gain & full from jump street right now.

Thanks Vortex! Marc
marchomeslice's avatar
marchomeslice OP
13 posts
 
p.s. I think I know which trim pots they are, but I can wait to speak with the designer.. thanks again for the heads up Vortex.
maineiac
649 posts
 
Ha, I have spent a great deal of time, effort, and funds tube rolling in my integrated amps but never even gave the tubes in my K&K a thought because it always has sounded so phenomenal, transparent, etc. I guess it would be worth a try.
vortrex
273 posts
 
in my manual it is in the "break-in" section. it's adjusted for each channel using R115/R215 while monitoring the voltage at TP2/TP4 relative to TP1 (ground). Kevin notes the original value as 1.6VDC, but says it is adjustable between 1.0VDC to 2.4VDC (higher number is more "incisive"). he notes to do this after the unit is fully broken in.

* I should note I have the last Maxxed-Out, but the MM only standard version. I believe this should be the same with yours though, since it is the same board, etc.
marchomeslice's avatar
marchomeslice OP
13 posts
 
Just heard back from Kevin. He said to leave the trim pots alone on my unit. Said he ran it in HIGH in the MC section and LOW for the preamp's overall output; which is how he shipped mine.

It did sound best this way.

It's still incredibly tunable.. there may just be some valves I don't love in this baby. I can live with that.

Plus, I still have to just let her break in first, before I can view anything too critically, me thinks.

Thanks! Marc
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