Review of the Little-Dot MKIII Tube Headphone Amp/Pre-Amp

[ManAtWork]

Originally Posted by bikeboy999

Some one asked about how the MKIII works with classical music, I am wondering what CDs have the best cleanest widest sound on them.

You don't need to worry about the positioning in the records with classical music; while most of them are recorded carefully for considering the accurate instrument positioning. If you want to find those kind of CD, you can refer to related CD reviews specific for audiophiles.

[.Sup]

does it work without the tubes? Is that what hybrid means?

[SemiAudiophile]

you know? i never understood how people found their little dot mk3 to match well with their HD650's. sometimes they sound alright together, but most of the time i find them too slow and laid-back. maybe you guys all have the newer 650's? the more forward less veiled ones?

[Dept_of_Alchemy]

Originally Posted by SemiAudiophile

you know? i never understood how people found their little dot mk3 to match well with their HD650's. sometimes they sound alright together, but most of the time i find them too slow and laid-back. maybe you guys all have the newer 650's? the more forward less veiled ones?

It depends on a few factors actually. First of all if your reference is a very dry and airy amp like the HeadFive for instance then yes the LD will not sound the same as your reference and people as a tendency of human nature generally prefer what they're used to. Second factor would be the type of tubes you're running on your mkIII, it makes a huge difference if you're running Mullard EF95's (which is on the warm side) or Voshod 6ZH1P-EV (on the neutral side) or one of the EF91 variants (on the bright side). Besides hackneyed 'house sound' arguments for why tubes sound different from one another, with LD amps there actually are technical reasons for why EF95 tubes would sound different than EF91 tubes - the effect of the difference in plate current draw on linearity in the top end is measurable - bottom line is you should be able to experiment with different types of tubes with your LD and find a sound that suits you.

Going back to your comment about the synergy with HD650 in particular, just for the record as an interesting trivia, all of the LD amps were designed by Sword Yang who used the HD650 as his reference headphone* to voice in the amps, so at least to the designer this amp has good synergy with Sennheisers.

*with the exception of the LD I+ which is designed for low impedance headphones

- DoA

[Max F]

I have the new "silver driver" HD650 and they don't sound veiled at all with the LD MKIII. They did sound veiled when using my portable amp though. Actually, no tubes that i have used with the MKIII sounded veiled to me.

Keep in mind though. I hate bright phones! The MS-1s about killed my ears!

[SemiAudiophile]

Originally Posted by Dept_of_Alchemy

Second factor would be the type of tubes you're running on your mkIII, it makes a huge difference if you're running Mullard EF95's (which is on the warm side) or Voshod 6ZH1P-EV (on the neutral side) or one of the EF91 variants (on the bright side).

hmm...that probably explains it. i've been using amperex 5654 EF95's and mullards M8161 EF92's. they do sound excellent with grado's btw, but any recommendations of EF91's that would sound good with the HD650's? i'm looking for a brighter forward sound.

[TubeStack]

I've read in other threads/reviews that the Mk III has a "loss of liquid mids and vocal intimacy" in comparison to the LD II++.

I have an LDII++ that is also doubling as a living room system preamp, and was thinking about picking up a Mk III.

But, I'm concerned the Mk III is too different in terms of liquid-mids, warmth, vocal intmacy, and general tubey-ness, in comparison to the II++. Is this so?

Also, if the Mk III is less lush/liquid mid-like than the II++, are there any tube rolling combos that help make it more like the II++?

[lescanard]

So I pulled the trigger and expect to receive my new LD-MKIII in about 1-2 weeks (sooner would be ok too). Anyway - I'll spend some proper time with the stock setup and am slightly noob-like with rolling tubes but for my information - any recommendations for my Grado 325is' with their low impedance for tubes? This amp will probably make me get some Senns again down the road and I love that I will have an amp that is versatile to drive both because I like both Grados and Senns. Thx.

[ScottieB]

Originally Posted by lescanard

So I pulled the trigger and expect to receive my new LD-MKIII in about 1-2 weeks (sooner would be ok too). Anyway - I'll spend some proper time with the stock setup and am slightly noob-like with rolling tubes but for my information - any recommendations for my Grado 325is' with their low impedance for tubes? This amp will probably make me get some Senns again down the road and I love that I will have an amp that is versatile to drive both because I like both Grados and Senns. Thx.

First, it was recommended to me to get an impedance adapter because according to David the Grados are a very tough load for the MKIII power tubes. I witnessed this when I tried my 325is and heard crazy distortion - even though the Senns sounded fine. So I had cantsleep make me one and it is very very nice quality - 1/4" to 1/4" 220ohm adapter for $40. Might wanna look into it.

THEN, I had a pair of Ediswan EF91/CV138 tubes that i thought were just kinda ok with my sennheisers, but I LOVE them with my 325is! Can't stop listening - they just really beef up the low end and give it some punch, while filling out the rest of the sound. It's just synergy and I was very surprised. Otherwise, the usual suspects sound nice with anything - the Voshods, the Mullard M8161, etc - check the tube rolling thread.

[dukja]

Originally Posted by ScottieB

First, it was recommended to me to get an impedance adapter because according to David the Grados are a very tough load for the MKIII power tubes. I witnessed this when I tried my 325is and heard crazy distortion - even though the Senns sounded fine. So I had cantsleep make me one and it is very very nice quality - 1/4" to 1/4" 220ohm adapter for $40. Might wanna look into it.

THEN, I had a pair of Ediswan EF91/CV138 tubes that i thought were just kinda ok with my sennheisers, but I LOVE them with my 325is! Can't stop listening - they just really beef up the low end and give it some punch, while filling out the rest of the sound. It's just synergy and I was very surprised. Otherwise, the usual suspects sound nice with anything - the Voshods, the Mullard M8161, etc - check the tube rolling thread.

This is interesting. I just got K702 and wonder if LD MKIII will ever mate it well. I read some negative post about this combo. So will this impedance adapter help K702 as well? Why it helps?

And thanks for the note on EF91 tube. I might try my M8083 with K702 to see what will happen.

[ScottieB]

Originally Posted by dukja

This is interesting. I just got K702 and wonder if LD MKIII will ever mate it well. I read some negative post about this combo. So will this impedance adapter help K702 as well? Why it helps?

And thanks for the note on EF91 tube. I might try my M8083 with K702 to see what will happen.

I'm no expert, but skylab said this over in the tube rolling thread:

"This is absolutely right. High impedance headphones like a lot of voltage, and OTL amps are good at that. Low impedance cans demand a lot of current, and OTL amps are not so good at that. "

The MKIII is an OTL amp, so it isn't great at giving a lot of current. So, knowing that the K702 are low impedance, it should help. I don't know if it would help it SOUND better, but it should make the power tubes work less hard and therefore last longer.

As for the EF91, I have no idea how they will sound, I've never heard K702s - all I know is I like them with my Grados.

[dukja]

Originally Posted by ScottieB

I'm no expert, but skylab said this over in the tube rolling thread:

"This is absolutely right. High impedance headphones like a lot of voltage, and OTL amps are good at that. Low impedance cans demand a lot of current, and OTL amps are not so good at that. "

The MKIII is an OTL amp, so it isn't great at giving a lot of current. So, knowing that the K702 are low impedance, it should help. I don't know if it would help it SOUND better, but it should make the power tubes work less hard and therefore last longer.

As for the EF91, I have no idea how they will sound, I've never heard K702s - all I know is I like them with my Grados.

Thanks a lot for the explanation, which I also gathered in the past few months (OTL for high impedance phones with large volt swing and low imped phones need current). I should make my question clearer that is I guess the adapter add up the load impedance to decrease the current which may protect the power tube but actually reduce the current to drive the phone, isn't that bad to SQ? (We should be able to figure it out by having some time refresh the EM theory )

I do learn one new thing from you that is in addition to so-so SQ, the low imped phone may actually kill the power tube prematurely. Good to know.

I have tried EF92 with K702 and didn't hear any bad effect. Your post provided a good hint to try EF91.

[ScottieB]

I didn't notice any changes to the sound with the impedance adapter - at least nothing major. YMMV as always, of course.

[nzstudent]

From above: "
"This is absolutely right. High impedance headphones like a lot of voltage, and OTL amps are good at that. Low impedance cans demand a lot of current, and OTL amps are not so good at that. "

How would 50ohm senn hd595s go with the MKIII given their impedance?

[kamme]

That's my current setup:

Winamp (FLAC+ASIO) -> Audiotrak Prodigy HD2 Advance DE -> Little Dot MK III (stock tubes) -> HD 650's

Burned the amp initially for 30 hours. I'm not an expert but the sound isn't veiled to me. The highs are airy, though bit laid back. They're not very bright. But I like that kind of presentation (tried other combos recently too). Mids are cozy and warm. Bass is punchy, though again, it's laid back somehow.

Generally speaking I'm amazed of the performance. I like the sound signature that this amp leaves. It has enough power to drive any cans it seems (using gain setting at 5, there is possibility to set it up to 10). Plus it does look really good on my desk