New hybrid amp by Little Dot, I+ - Page 42

Quote:

Originally Posted by jr41 

 

So, as per my previous post, I placed an order for the little dot I+ via e-bay on 15/08 and began the patient wait to receive my first (hybrid) tube amplifier. I received a useful e-mail from David that evening setting my expectations RE delivery etc. David said to wait 3-6 business days for processing and a tracking number. Sure enough, on 22/08, I received another e-mail with my shipping ref. Then, to my surprise, my amplifier arrived the next day!

 

To give you a bit of context, my previous setup consisted of the uDAC > Sennheiser HD 25-II. Now the I+ sits between them and I'm using the uDAC purely as a DAC (oh and I brought some £3 OFC shielded RCA interconnects off ebay). See my sig/profile for more detail RE my setup.

 

I think I've got around 8 hours of listening on the amp so far. The change in sound by introducing the LD I+ into the mix - instead of using the uDAC headphone out - is subtle. I've noticed a tinge greater warmth, smoothness and space. Treble harshness (experienced previously when listening to Joni Mitchell's Blue, for example) has been tamed. Those are really the only observations I feel confident making at this stage. I suspect I may have lost a hair of detail, this is especially apparent during the first half-hour or so of listening, while the amp warms up.

 

The consensus RE the uDAC appears to be that the headphone amp section is on the warm side, and given the LD I+ isn't a true tube amplifier as I understand it - incorporating a SS element, may account for the subtly of change. That, and the fact it doesn't have many hours on it, and I'm running the stock tubes.

 

Once warmed up I can hear a humming noise (though not with headphones on) emanating from the amp. With the uDac's volume knob set at 3 O'clock, 9 O'clock on the LD I+ is too loud, but there is plenty of room for adjustment in this range. Cranking the LD I+ volume all the way up reveals no hiss whatsoever to my ears.

 

I wasn't expecting to be blown away by the LD I+ - especially given it's price and hybrid design (I'm not saying hybrid amps are inherently bad, I just didn't expect it to be worlds apart from other SS amps, vs. pure tube perhaps), and I'm not at this point in time. I'm certainly happy enough with it to keep it in the chain and I look forward to any improvements resulting from further burn-in. I will also be experimenting with better tubes and opamps of course; I've just started working my way though the LD I+ tube rolling thread. I'll post any further changes I observe.

 

A couple of pics of the LD I+ in situ:

 

 

Throw in some LT1364CN8 OPA and be amazed, the stock one is just crap. Also, replace those stock tubes with WE408A.
 

So is the LT1364CN8. It has more sibilance than a room full of pissed off cats.

@jr41, try a power cable minus the ground prong. If the humming noise goes away you got a ground loop. =(

This amp seems very susceptible to the. I myself had to pretty much buy an optical dac to get an elegant solution to the issue. But thankfully I got the perfect audio setup for my needs. =)

X-Fi (for gaming, music, movies, etc) -> MiniDAC (SMSL) -> I+ -> SR325i/Shure SRH840

As of right now, both op amp slots in amp and dac have the OPA2107 in it, which is just a phenominal op amp. But a bit pricey. I managed to get 2 for 10$. =)

Tubes are M8083. Of all the setups I've tried they are the least fatiguing and I can't hear any sibilance or any other wierd issues. I tried the LME49720 (hell I bought 4 of 'em just in case) and still didn't like anything besides the 2107.

Quote:

Originally Posted by Aynjell 

So is the LT1364CN8. It has more sibilance than a room full of pissed off cats.

Well, that is like your own opinion, man.
 

@reiserFS and Aynjell,

Thanks for your advice guys, it's appreciated. I'm working my way through the LD I+ tube/opamp rolling thread and both the LT1364 opamp and WE408A tubes are favorably mentioned there.

The humming noise is from the amp itself, it's not coming from the headphones. As I understand it, ground loop is only audible from the headphones? I've read up a little about it and it appears it's the transformer that is humming, which apparently isn't uncommon and nothing to worry about (though I will look into it a little further to be sure). Also, it's only an intermittent thing.

Have any one tried this with a pair of AKG 701/702s. i saw this on ebay also when I was looking at a standalone amp for the future.

Quote:

Originally Posted by genclaymore 

Have any one tried this with a pair of AKG 701/702s. i saw this on ebay also when I was looking at a standalone amp for the future.

Not sure if I have posted my opinion about that combo in this thread yet, but the LD I+ does a wonderful job for the K701/K702 with the LT1364 and WE408 / Mullard Tubes. If you're looking at a budget build, this probably is it.

Quote:

Originally Posted by reiserFS 

Well, that is like your own opinion, man.
 

I'd be inclined to disagree and note that sibilance is pretty measurable. The rest of the qualities of the LT1364 are enjoyable, but the sibilance is a deal breaker. A BIG back of pissed off feline dealbreakers.
 

Quote:

Originally Posted by jr41 

@reiserFS and Aynjell,

 

Thanks for your advice guys, it's appreciated. I'm working my way through the LD I+ tube/opamp rolling thread and both the LT1364 opamp and WE408A tubes are favorably mentioned there.

 

The humming noise is from the amp itself, it's not coming from the headphones. As I understand it, ground loop is only audible from the headphones? I've read up a little about it and it appears it's the transformer that is humming, which apparently isn't uncommon and nothing to worry about (though I will look into it a little further to be sure). Also, it's only an intermittent thing.

I want to point out my amp doesn't make any sound. I would check with davidzhezhe on this. And jr41, we've had a LOT of flavors of the week.

The only thing that's stuck around is the OPA2107 (for me), and that being said I'm probably going to upgrade to what it's supposed to be mostly, the opa637 or whatever. if that opa is just MORE... then I want it, regardless of price.
 

Does anyone knows how LDI+ stacks to Heed Canamp if they are used with k702 ?

Is there a way to use it where your just using the SS thats in it and not the tubes. Or when your using it you have to use both the tube and the SS together?

The tubes are basically there for flavor. The ss part handles the actual amplification.

That's the way I understand it anyway.

Hey Aynjell, did you get around to trying out the opa637?

Quote:

Originally Posted by Suigeneris 

Hey Aynjell, did you get around to trying out the opa637?

Nope not yet, but anybody believe this is real?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&Item=350390352506&Category=36331&_trkparms=algo%3DLVI%26its%3DI%26otn%3D2

I've seen them for 18.04 from TI
 

Here's a link, ARROW electronics is the company selling it.
If you end up buying it make sure to let us know, I'm barely going to

try out the 2107 in my LD

http://app.arrownac.com/aws/pg_webc/0,1086,,00.html?application=SEARCH&event=1009&search_token=OPA637AP&search_criteria=match_begins_with&match_in_stock_only=NO&=&rows_to_display=10&limit=10&full_domain_name=app.arrownac.com&super_neda=&start_index=0&search_type=click_through

I just ordered. It's supposed to be the OPA2107's bigger brother from what I hear, and I can handle 22$. Let's see how it goes when I get it. If it's the big brother I'll undoubtedly love it. I bought the ebay one, doubtful it's real but I was doubtful about my opa2107 too... I got 2 for 9.99. That ebay auction is for 2 with the adapter. Basically, a plug and play dual op amp based on OPA637's. I'll have to bring my gain up to 7 though. :(

Also, now that I hear the K701/702 is awesome with this amp (the specs basically are textbook example of K702 amp from hell) I'm gonna have to get a pair. :)

Question is, upgrade my DAC to a Little Dot DAC I or a pair of K701/702 first?