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Little Dot I+ Tube Rolling - Page 26

post #376 of 1359
PatOMalley: Interesting dealings with the opamp capping, got my interest sparked.
I was supposed to get rid of my MkV, and did, but ended up succumbing to wanting to know synergy of a LD hybrid with my D1001, i have the MkII for my HD600 and through that, a way too large stock pile of tubes, so this should be interesting, especially since you do interesting things with my favorite opamp (couldn't stand the weak bright sound of the MC33078P in the MkV, and loved the MkV with LME49720)
I picked up a I+ used (in transit), so i actually get LT1364 and OPA2107 to play with, I'm gonna get me another LME49720 and a couple caps.
CV4014/EF91 tubes are still my favorite.
Thanks for the mod suggestion, i may need to come up with a way to make this "switchable" i never looked at sockets, could i solder this to a socket and then use the opamp in this socket and the sum of both in the amp's socket? :>


I guess i am alone with my "better many cheaper tubes than one pair for $50+" thinking. I rather have 10 pc 6J1P-EV which are an amazing upgrade over the (not actually bad at all) stock tubes, than one hard to get pair that after maybe ~1000 hours has to be replaced.

I can pick up another pair of EF91 or 6J1P-EV if the currently used pair gives out.
Should i sell both amps and no longer have use for that many tubes, i can sell them for $3 a piece and not have lost much if anything.

The suggestion in one post, that a guy can't find a nice upgrade for $25-30 shipped is pretty wild and exactly what ebay sellers like yen1233 "pray on" (harsh but not too harsh) (Think of him picking up a lot of 100pc for $120 shipped, and spending a few minutes "matching" them, it's selection nothing more. So here are 2 6ZH1P-EV for $24 plus $8 shipping that cost him $2.40....let's be fair and say he needs to make a living....$4.80 is a 100% markup, heck he just bought a new car.....$9.60, still not $24 )
If you would know your likes are like mine, i could suggest you one pair and then you could say "Hey those will be exactly what i want.", but taste is so different, i rather afford a few different ones and am able to pick my favorite from that.
"But what about all the tubes you bought and now don't like?" you ask? Far from it, i have favorites, but when i switch tubes i often find myself liking certain tracks more with certain tubes that day.
"Why do you switch so often?" you ask, well if you have 3-4 pairs and they all ask to be burned in you run some 8 hours, switch, run them 8 and so on, what started as a necessity, can turn into fun.

In short: i would encourage anyone to experiment, limit the set of what you try by what you learn in these threads, but don't waste your money on $50 pairs.
Oh, and head over to the Little Dot MkIII tube rolling thread, they can't use 408a, but that aside, lots of interesting stuff there, and if you see someone proposing to not pay more than $8 a tube, yes i read the post, and i like it, cause i have seen what forums can do to used (adapated) lens prices.
post #377 of 1359

sockets

Yeah, the best thing would be to place the cap under the board on thsoe pin and run to ground from tehre. Then you can plug and play with any opamp without any more soldering.

I just didn't want to take the LD apart. And I get to use those modded opamps in any socketed board so for the future I have some thing finished and portable.
post #378 of 1359
you got the manual handy? how do i set which pins to adjust gain?
my used I+ did not come with a manual
post #379 of 1359
jumper settings can be found here: Little Dot I+ mods
post #380 of 1359
Correct me if i'm wrong, that is addressing the tube settings.

Little Dot lists I+ having:

# User variable gain settings: 6.5x or 3.25x

I guess it's jumpers J3 and J4, but am hesitant to just pull them off to try difference.
I+ is driving my D1001 very poorly right now. Much less than MkV did, and the power of the I+ at 32Ohm should outdo the MkV easily.
post #381 of 1359

updated

morfic,

I just updated my page with a scan of the manual showing settings for gain.

post #382 of 1359
Thanks! This is good news, J3 and J4 are capped, so i am at half the possible gain, this is going to be fun trying it all again uncapped!

Thanks again!
post #383 of 1359

noise

let us know if it's noisier when you increase the gain.
post #384 of 1359
What noise are you asking about? i Just plugged my D1001 back in to see if i can hear hiss, but even at 100% volume with source connected but paused there is hardly any audible hiss, i hear nothing suggesting i get USB bus noise into this, which is nice.
I'm trying this with the D1001 since the 32Ohm make finding hiss easier, with the HD600 that i am using to evaluate the I+ (since i know it's sound with the MkII + EF91 the best) and their 300Ohm, i know of no hiss or noise of any kind. They are black on anything.

When i first connected the I+ to the Pro-Ject USB Box i was underwhelmed, i had issues driving either phone. I switched the Mullard EF92 Small Shield to the I+ and tried the Mullard Large Shield the I+ came with in the MkII. (on the small shield large shield front, i am glad i never hunted for large shield, i can't tell them apart)

I rechecked the I+ but only went ahead switching my burned in EF91 to the I+ and left it alone, connecting my new source to the MkII, after i got the Transit working in linux i proceeded to listen to the Transit on the MkII (fresh pair of EF91s installed meanwhile)
Got to like my new source.
Back to the I+ with my HD600 and Hello! something must have been wrong at first because there it was loud and strong. I listened to some tracks i know pretty well and it sounded great on the HD600 (considering the I+ is made for low impedance phones).
Tried the LT1364 that came with the I+ next (came installed with OPA2107) and yes, i do prefer LT1364 over OPA2107, but w/o a LME49720 around i can't say much about the LT1364 in comparison.

The I+ with CV4014/EF91 Mullards (white box, no shield, KQDD/K labeled) and LT1364 has the full package, airy, clear vocals, both female and male, nice low extension, be it drums, bass plucks, or low cello notes, it's all impactful.
Cymbals seem to come out a little more right now with this combination, and snares sound like the metall bands hit against a tighter tensioned membrane.

So far I'm loving it, Gain 6.5 (7?) is no problem at all, and I *think* it reminds me more of the MkII than before, very dynamic, musical, *FUN* (I had felt the music became flat when i switched MkII from Gain10 to "true" Gain 5, the change from 3.5x to 7x reminds me of that, just in revers of course)

I meant to test the amp with certain songs but found myself stuck listening to more from same album, that's *FUN*
As much bass as i have right now on the EF91 (have a nicer low extension than the EF92 Mullards btw) i am almost scared to try any 6AK5 or my "bass when i need it" 6Zh1P-EV
Going from 6Zh1P-EV to EF92 Mullards used to show the Mullard's rolled off bass in particular. (EF91 are like EF92 + more low end to me)

I could go on for hours about this, but i rather go enjoy my music w/o my eyes glued on screen


Thanks for the scans and the mods, i will have to go place an order for sockets, foil caps and most importantly LME49720 tonight,

Daniel
post #385 of 1359
Put in the EF95 ("The Russians") which i am used to giving me a lot more punch for the $ compared to EF91, and wow, sounds almost like i didn't switch tubes at all.
Very very similar in sound. (So similar i am wondering what actually may be wrong, switching from EF91 (Mullards) to EF95 (Russians) is so easy to pick up on MkII)

I think I'll reserve testing the EF95 mullards (CV4010) that came with the I+ in the MkII, where i can hear and appreciate the tube differences much easier.
post #386 of 1359
I tried to not worry about it since the amp plays quite nicely, but how much glow do all your 6ZH1P-EV emit? or if you got any EF91 Mullards?
My tubes in I+ stay at best warm to touch and emit no visible light except for the very tips, in MkII they are hot and have a visible (even in daylight) glow.
I wonder if my heater voltage is correct?! (And i do get the same effect with the amp properly set to EF95 or EF92, i verified this a few times over, i don't mean set wrong, i mean heater voltage wrong if properly jumpered)
post #387 of 1359

heat, light

My Amperex give off a glow after power on but not a flash that dies down.
The 6J1's gave off a similar glow but the Amperex are brighter.

So the Russian tubes sound worthy. What is a good source?
post #388 of 1359
Thanks, does seem my tubes are not running the way they should on the I+.
Considering i am quite happy with the performance, i wonder if it worked even better with a properly working heater.

I got a batch of 10 6J1P-EV from a Ukrainian seller (denys24something, i got 6 from '71, 3 '74, 1 '72), got two 6J1P another Ukrainian (non -EV, sound the same, from xryn), both packages made it here in under 10 days.

'71, '74, '77 (foolishly bought from yen1233) all sound the same, some have the ridges in the glass, some do not, their performance is great no matter the year.
6J1P-EV sound like the stock 6J1, with more detail and air, and seem to have more depth, like reverbs seem deeper.
post #389 of 1359
http://www.zerorealm.org/LDI+_LDMkII.htm
RightMark Audio Analyzer test: comparison[/url]
I think it nicely shows the extra distortion from the cold tubes.
Going to update this once i have been able to adjust my heater voltage.
post #390 of 1359
Heater voltage *IS* low, 5.2V to be exact.
Almost an exact 1V drop.
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