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Little Dot I+

100% Positive Reviews
Rated #9 in Desktop Amps

Posted

Pros: Price, Construction, Sound-tailoring Options

Cons: Power, Chassis Design (sort of)

The I+ from Little Dot is an excellent tube hybrid that offers much more than its sub-$150 price tag would suggest.

 

This is the first piece of head-fi equipment that I've owned twice. Bought one from a fellow Alabamian head-fier a couple months ago and had it for a little more than a month before deciding to sell as my "best" pair of cans weren't benefitting as much from amping. Within a week of the sale, I missed the LD too much and pulled the trigger on a new one! (Oh well, you live and you learn).

 

I purchased the I+ after reading up on how well it pairs with Grados, my flavor of choice. And let me tell you, it certainly performs brilliantly!

 

1st: Price: Inexpensive. These can be purchased from Little Dot's webstore for ~$140 shipped to North America and currently from Amazon for ~$120 with Prime shipping. For a hybrid tube amp with tube/opamp roll-ability, excellent sound and sturdy construction, why keep looking? This is it!

 

2nd: Design: Simple. 1/4" plug, volume pot, RCA inputs, and power supply. That's what you get. All sturdily built and thoughtfully implemented. While we're on the topic, the thick aluminum frame of the I+ feels great and hasn't shown any signs of component failure or weakness. The board is assembled very well and when I open it up to change the opamp, I don't feel afraid to touch the I+'s innards. Ain't nothin' goin' nowhere. The volume pot also turns very smoothly, the tube sockets are of sound quality, and the included power supply doesn't make me feel like LD tried to cut corners.

 

3rd: Sound: Natural. Since the I+ is a hybrid, the syrupy smoothness a.k.a. "tubeyness" is tempered with the detail and resolution of solid state technology. IMHO the LD is the amp equivalent of the Colorfly C3's sound: organic, musical, and neither so flat that it sounds boring nor so fun as to seem artificial. The best is yet to come however - you can roll tubes. AND opamps. 

 

Options for tailoring your sound are virtually endless. Thanks to its interchangeable jumper capabilities, the I+ accepts tubes from the EF91, EF92, and EF95 families (not to mention others that may have to be adapted). That's plenty of tubes! From the punchy detail of the Voskhod 6ZH1P-EV to the buttery smoothness of the Tung Sol 6AK5, sound signatures are easily changed just by swapping tubes. The circuitry within also makes the I+ very quiet (as in noise floor) and it will warm tubes rather quickly. Opamps are also swappable, any DIP8 will fit (along with any that will fit onto a dual-to-mono adapter), so yet again, sound-tailoring is easy and abundant. So whether you're a vinyl junkie yearning for the super smooth tube sound of yesteryear or a digital wizard who likes the ultra modern edge of solid state, you can modify the SQ of this little amp quickly and easily to your taste. 

 

As far as cons go, there aren't any real issues, just a few shortcomings that I may as well mention. 1. This is not the most powerful amp in the world. It will power all but the most hungry cans so, if you have THE MOST HUNGRY CANS, you may want to keep looking. 2. Opening the chassis to swap jumpers or opamps is a little inconvenient. Just to swap one or two pieces of plastic, I have to remove all 8 screws. Not hard to do, but the screws that hold the base to the upper half are tiny and sometimes hard to re-screw. Not to mention they are a part of the ground circuit, so if you lose one, you may open your amp up to noise. EDIT: Don't know why this didn't dawn on me, but I could just loosen the lower 2 screws on each side to open the amp up... Whoops!

 

So overall, the LD I+ is an excellent choice for those looking to get tube capability with plenty of variety available for tube/opamp rolling. The sub-$150 price tag makes this amp very affordable and the quality design makes operation very easy. I certainly recommend!

 

P.S. It plays wonderfully well with Grados. Enjoying Kind of Blue with my 325is as I finish this review!

Posted

Pros: Amazing value, good sound, it looks nice (IMHO), good for Grado, Denon, and other efficient headphones, great build quality

Cons: Only one input, not the most powerful amp ever created, needs an upgrade from stock tubes

For $140 (Shipping included), this is probably one of the best amps out there. The Little Dot I+ is a great inexpensive chi-fi amp and with a small tube upgrade (I upgraded to Mullard M8161 tubes) it is a great budget solution. I know I didn't really want to spend a lot on an amp as I am still in high school and living on a strict (sorta) budget. I am using this in conjunction with an iStreamer from HRT and Denon AH-D5000 headphones and it really shines (for the price of course) with this system. Build and design are very good (Again, IMHO). I think that it is the simplicity of one analogue input that can keep the price down and really just make a straight foreword beginner amp. Another great value product from Little Dot!   

Posted

Pros: Sonic Presentation, Build Quality, Rolling Capability, Driving Power

Cons: Stock Volume Pot



 

Me: I am a 21 year old student living in a small town in India. I would like to call myself a music enthusiast, rather than an audiophile. I was inspired by music since childhood, and as the time passed, the passion of music grew in me, and that subsequently led me to join Head-Fi. Eventually, I found the pleasure of listening to music mainly by the HD600 and recently, by the seductive LCD2 headphones, and realized the true components of recorded music. I usually like to listen to Indian Classical Music along with Bollywood songs. My main listening genres include classical, vocal, instrumental, jazz and sometimes pop.

 


 

Intro:  Little Dot is a famous Chinese brand specializing in the area of Tube Headphone Amplifiers. They are rolled out their first product around 2008. The 1+ hybrid is the entry level amp offering from Little Dot.  

 

 

Those days, OTL/tube amps would be expensive, and out of reach of a humble Enthusiast. Little dot products made well performing OTL amps in an affordable price. This made them a well known name across the Audiophile World. Little Dot have a specific vision in making their products: The products should have appreciable sonic performance, quality and should have a practical operating aspect. All their products are handmade by good workmanship. Mr. David & Mr.Yang are the key people behind Little Dot.

 

Specifications of LD1+:

 

THD+N:

 

0.2%: 1Vrms @ 1000Hz

 

0.6%: 3Vrms @ 1000Hz

 

1.0%: 5Vrms @ 1000Hz

 

Signal-to-Noise: 92dB

 

Headphone Impedance: 8 - 600 ohms

 

Input Impedance: 50K ohms

 

Power Output:

 

150mW @ 300 ohms

 

300mW @ 120 ohms

 

800mW @ 32 ohms

 

User variable gain settings: 6.5x or 3.25x

 

Power Consumption: 15VA


 

Let us see what the LD1+ has got for us,

 

Packaging and Accessories: The LD1+ arrives packed inside a general cardboard box, packed inside a removable foam packing. Tubes are included inside the foam socket. Default tube included is a generic 6J1. Packaging is generic, but nothing to complain about. But all the included accessories have a good quality and feel to them.

 

List of accessories in the box, which include the following: 

 

RCA Cable:  One short 1.8M RCA to RCA cable for input connection.

 

¼” Converter: To plug in the 3.5mm headphone jacks in the 6.5mm sockets.

 

Power Cord: A mains AC power cord EU/US/AU/UK is supplied as per specifications.

 

User Manual: Contains instructions to operate the 1+ and other warranty information.


 

Design and Build: The LD1+ has a very good overall build quality. Its design is very practical.

 


 

The entire case is made up of high quality brushed aluminium, and is painted in gloss black, which is a finger print magnet. The LD1+ fairly large in size, and just appears to be smaller in pictures. It feels heavy when held owing to its 1.5 Kg weight (thanks to strong & reliable transformer). At the front we have a volume knob, ¼” headphone output socket, and a blue indicator LED. At the rear side of LD1+, we can observe the presence of power socket, power switch, and RCA inputs.

 

 

Volume knob rotation is smooth and knob has just the right size for fingers. ¼” jack is also a very smooth operator, which is neither too tight nor too loose. The ¼” socket employs ball bearings instead of clips to avoid scratches/damage on the headphone jack. Power switch has a pretty great operation and strength, and is very precise in its job. RCA jacks are gold plated, and the plating wears off along with the time. Since Little dot amps are hand soldered and assembled, I feel soldering and assembling could have been done in a more precise or in a neat way. The volume pot along with most of the components is of generic make, which is quite disappointing, but this is to be expected as LD1+ has a very competitive pricing.

 

 

The 7 pin Tube sockets are ceramic type, have a great build. LD1+ accepts single pentode or triode type vacuum tubes. Matched pair is technically not essential for operating the LD1+, however matched pair does add up to proper channel balance and slightly better performance. LD1+ is a very versatile and customizable hybrid amp, users can roll different op-amps and three families of vacuum tubes as per their tastes.

 

 

The only downside I observe here is, bottom chassis has to be removed every time to change gain/tube settings. This is not really a drawback, but it would be more easy and convenient for users (especially for tube/op-amp rollers) to do this way.

 


 

Sound: The LD1+ has a slightly rich, euphonic  yet airy sonic character. ‘Musical presentation’ is the key word. I find it very appealing and pleasing.  Presentation is in such a way that, mids are little more intimate, with lows & highs sound tad more relaxed and laid back. Stock tube and op-amp is pretty mediocre and needs to be changed/upgraded. I also recommend changing the stock volume pot to Alps-16 100K for further improvement in SQ.

 

Burn in: These improve a lot with time. Let’s say a playback of 50 hours provides few audible improvements, Bass prior to break-in is quite muddy, and eventually it becomes more accurate and clean, Mids will sound more open, airy and natural. highs become slightly more smooth, soundstage will open up by a margin.

 

Op-amp rolling: Any dual precision audio op-amp will work on LD1+, but there are few renown and high performance audio op-amps, &  after trying on many, like, 2134NA, 4562NA, 6171,6172, 2111KP, 49720HA/NA, 49860NA, 49990MA, OPA209/627 /827 I have settled on 2X LME49710HA (metal cans) on browndogs. This results in a very detailed, natural, airy presentation with precise and lifelike soundstage.

 

 

With stock op-amp, LD1+ runs fairly cool. With replacement op-amp, amp runs warmer by about 20%, But with op-amps mounted on browndog, Surface temperature rises by 40% (probably due to power intake by op-amps)

 

Tube rolling:  One can roll 6J1/6AK5/5654/WE403A, WE408A, EF91/92/95 family tubes on LD1+. Essential thing to do is set jumpers before tube rolling. Failing to do so can burn up tubes or damage the amp itself. Out of all these, The Mullard EF91, Yugoslavia 6HM5, and Voshkod 6ZHP1 tubes particularly match pretty great on LD1+ and result is a very clear, clean and airy sound with a lifelike 3D soundstage. And the good news is that all these tubes are available at 20$ a pair shipped on ebay!

 

I can conclude op amps have overall 30% effect on final sonic character of LD1+, whereas tubes have around 70%. So tube rolling can bring major audible changes than op-amp rolling.

 

The LD1+ has a solid power supply which delivers. No distortions, works great even when directly plugged into mains (no need for power purifier etc like some tube amps) No distortion/ out-of-breathness found on any combination of op-amps or tubes. There are gain jumper present (J3, J4), which if removed provides an high gain of 7X (ideal for 300-600 ohm cans). Else jumpers engaged will provide a low gain of 3.5X (ideal for Planars and low impedance dynamic cans) I also can confidently say that EF91 + LME49710HA is the best possible combination on LD1+ for all planar magnetic headphones.This amp is pretty powerful and can drive demanding cans like LCD2’s in low gain and less than 50% of the volume pot.

 

Lows: are accurate, tight and refined; have a good impact. Depth is pretty good.

 

Mids: sound very natural, and appealing, and have a prominent warmth and lush (I guess that is in a good way, comes very pleasing to our ears). Tonality particularly, one of the best at this price point. This character makes LD1+ a strong contender for vocals.

 

Highs: Very smooth treble without grains and sparks. Highs convey an image of smoothened darkness, just like a caramel chocolate. Highs are airy with good amount of space sensation.

 

Soundstage: Soundstage is airy, natural and circular. Depth is excellent. Instrument separation & detailing is pretty good. With the default Chinese 6J1, tonality is a bit harsh, and soundstage is limited. But once you pop in the upgrade EF91, soundstage very 3D, airy and clear. At this point, the 1+ shows a hint of its potential.

 

LD1+ portrays music in such a way that, one feels as if the music is all around him. The sonic character here is so natural and eased that the tonality sounds very life-like. According to my observation, these cans sounded good in all genres I tried, and hence I conclude LD1+ are not very transparent, and are forgiving to poor recordings. Hence these are not resolving, but very musical in character. 


 

Comparison: The main competitors of LD1+ are the Bravo Ocean & Schiit Vali along with Project Starlight which are all similarly priced. All these are hybrid amps.

 

Bravo Ocean: Hybrid amp which uses mosfets for amplification. Mosfets have their own kind of sonic touch to them, which I quite don’t like. Power supply is external DC type and not well made (which results in higher noise floor, light electrocution) But as a advantage, Tube rolling is very economical and convenient here, since Ocean supports a single 12AU7, which are very common to obtain & no hassle for a matched pair.

 

Summary: Just like a Bravo V2 on steroids, small & powerful. Most economical of all, easy tube rolling. But noise floor, power supply are a question mark.

 

Project Starlight:  At 225$ built & shipped this is the most expensive amp of the bunch. But Starlight has best internal build quality (along with Vali). The Starlight is not fully enclosed in a case. Its output power at headphone is quite limited, and is lowest of all these amps. Starlight also has a op-amps and support for 6/12V Dual Triode tubes. Starlight is specifically suited for lower impedance & less demanding headphones.

 

Summary: Best option for DIY’ers & Tube/Op-amp rollers. But expensive, driving power is not the best.

 

Schiit Vali: Has no rolling options. Everything is fixed in. Output impedance is quite high at around 6.5 ohms and is not suitable for IEM’s. Power supply is again external, but definitely better than Bravo Ocean. Vali uses 16V AC/AC adapter (similar to O2 amp adapter) Vali also has a best build quality.

 

Summary: Good choice for beginners who don’t want to roll anything. A nice amp for 50-300 ohm headphones.

 

Ultimately the LD1+ has an edge over all tube amplifiers to be tried in 200$. LD1+ cleany sweeps out Vali, Ocean & edges out the Starlight.  We can observe here, the competing amps lack one or the other feature with them, but LD1+ has them all. LD1+ is an allrounder. It has dedicated, strong & reliable internal  power supply, can drive anything from 8-600 ohms, gain is changeable, comes in a excellent built case, one can roll tube/op-amps (even without matched pairs)


 

Conclusion:  I feel the LD1+ is a phenomenal hybrid amp. Build quality is very good, sonic presentation is very pleasing, it can drive almost any cans & its sonic character can be tailored to meet one’s taste. I can whole heartedly recommend LD1+ for any enthusiast who would prefer a musical (or magical) sonic presentation. I am absolutely in love in LD1+. I can safely bet, that LD1+ is best sounding hybrid amp in 200$ range. 

 

The LD1+ is a clear winner.

 

 

Pros: 

 

1) Build Quality: The LD1+ has a very good all-metal build. No compromise to be seen anywhere in exterior.

 

2) Sound quality: Sound presentation here is very natural, detailed and spacious, which is very much like-able for music listening. Sweet mids deserve a special mention. Tubes for a natural presentation and solid states for accuracy. Best of both worlds.

 

3) Rolling Capability: Enthusiasts can roll tubes, op-amps to match their sonic tastes.

 

4) Driving Power: The LD1+ can comfortably drive any set of cans from 8-600 ohms. Good job!

 

Cons:

 

1) Internals:  Actually not really a con, Infact there are just three components which I feel one should upgrade. these are volume pot, stock tubes and op-amps. But once upgraded, LD1+ is a beast unleashed!

 




Posted

Pros: Solid build & clarity of sound; affordable

Cons: Power and maybe aesthetics

The Little Dot line of headphone amps represent what is possible when a Chinese production amp doesn't cut corners on build quality and engineering. This amp has my vote as the best desktop hybrid amp in the price range.

 

Build/Design

 

The build quality is very solid; the housing is all metal with a very smooth and clean-looking volume knob. The amp is also quite heavy. The design is very plain however, which is fine, but a little boring. 

 

What really stands out in the design department is the choice of tube socket/settings (WE408A, EF92, and EF95). Both WE408A's and EF95's are very affordable and effective replacements for the unimpressive stock 6JI's. The 6ZH1P-EV Voshkhods for example are available through eBay from Russia or Ukraine for less than 15USD per NOS pair. Another favorite of mine is the GE JAN5654, which I found for 3USD for a NOS pair! If you want to splurge, EF92 Mullards (M8161) are also a great option. But to play devil's advocate, a user on AudioKarma ran some tests on the circuit and concluded that tubes contribute next to nothing to the circuit. 

 

Along the same lines, the op-amp can also be rolled since the LDI+ has a no-solder DIP-8 slot installed rather than a surface mounted or through-hole soldered op-amp. Personally, I think op-amp rolling is a waste of time when comparing op-amps above the 1USD mark. For example, an OPA2134 (~4USD) is hard to distinguished from an OPA2107 (~15USD) or MUSE02 (~30-70USD) but is probably better than the stock, which is worth less than a dollar.

 

Sound Quality

 

The sound you get is somewhat dictated by the tube you roll since this hybrid amp does rely on the tubes for color (whereas most of the amplification is done by the solid state components). Whatever tubes you roll however, the sound is very clear and balanced, which is what you want out of an amp barring any coloration you desire from the tubes. Detail is also great on this amp, especially with a good pair of open or semi-open cans like the DT880. Higher impedance headphones also benefit since the output impedance is said to be around 30 Ohms. A quick overview of tube impressions and reviews are available here: http://www.head-fi.org/t/364043/little-dot-i-tube-rolling

 

The only demerit for this amp is the relatively low power compared to other amps in the price range. For my 250 Ohm DT880's, it takes about 70-80% on the volume knob to get good volume for modern mainstream recordings and full volume to enjoy classical recordings (which tend to be much lower volume recordings). The gain can apparently be changed internally, but this is annoying if you switch between different headphones of different impedances.

 

Overall, I love this amp and powers my home headphone setup. A great option for all except the most frugal shoppers of HiFi devices.

Posted

Pros: Amazing for the price

Cons: Gain has to be changed internally

Amazing headphone amp for the price.  Used with my 325is, Pro900s and Q701s.  Great value, drives most headphones incredibly well, even powered my Q701s on the high gain setting with no signs of distortion.   It's a really nice looking headphone amp for the money also, very study with a neat, clean build.  For the price this absolutely can't be beat.

Little Dot I+
Description:

The Little Dot I+ is a hybrid transistor-vacuum tube headphone amplifier, which combines the smooth, musical sound of tubes with the high output current of transistors. The vacuum tube stage is run in Class-A, the MC33078 operational amplifier (socketed) provides voltage amplification, and BD139/BD140 transistors serve as output buffers. The Little Dot I+ is specifically designed and optimized for driving low impedance headphones that require high current to perform to their full potential. Depending on how the switches are configured, three different families of vacuum tubes can be used (EF95, EF92, and 408A). With two gain settings and DIP switches for vacuum tube rolling, the Little Dot I+ offers versatility in a tiny footprint!

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