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Tube Question

AMKAM

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This will be my first tube amp.
I am interested in xDuoo MT604 and xDuoo TA-26.
Most of my headphones are unbalanced and yes i know the MT604 is fully balanced and here is my Q, as it has 4-pin xlr can i use 4-pin xlr male to 6.5 female.
Both devise are highly appreciated by Z reviews. I am really interested in xDuoo MT604 for its large sound stage.
I am not looking for specific sound as i dont have any experience with Tubes but in general i like warm and wide sound stage. I have seen a lot of tube amp reviews so i know what a tube basically do to a sound.
These are my headphone collections
DT-770-80 ohms
AKG-K712 pros
Fostex- t50rp Mark 3
Harmonicdyne Zeus
paired with Zen-dac and Zen-can.
 

Turambar

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I own the MT604, and I have made a quick test. I have used a 4.4 male to 3.5 female and it works (i.e. it produces sound), so your 4-pin xlr male to 6.5 female should work too.

In my view, if you are mostly after warm sound, probably it should be better to buy the TA-26.
 

_thelaughingman

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Both of the tube amps you've recommended are hybrid tube amps. They're not OTL amps, so you might not hear the warmth that has been touted of a tube amp.
 
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AMKAM

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I own the MT604, and I have made a quick test. I have used a 4.4 male to 3.5 female and it works (i.e. it produces sound), so your 4-pin xlr male to 6.5 female should work too.

In my view, if you are mostly after warm sound, probably it should be better to buy the TA-26.
Wow Thanks for quick reply
how does MT604 sound in your experience and how is it in the details and imaging.
i like to use it for movies as well
 
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AMKAM

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Both of the tube amps you've recommended are hybrid tube amps. They're not OTL amps, so you might not hear the warmth that has been touted of a tube amp.
in layman terms ur saying that this tubes are half class_A amp right?
if so what other tube amp would recommend for warm and large sound stage.
 

Turambar

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To my ears, it's producing a slight coloration of sound in the direction you are looking for, but nothing dramatic. That's why I would purchase the DA-26 to get a bigger "tube" experience.

The DA-26 is not hybrid, it's full tube. The MT-604 is hybrid.
 
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AMKAM

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To my ears, it's producing a slight coloration of sound in the direction you are looking for, but nothing dramatic. That's why I would purchase the DA-26 to get a bigger "tube" experience.

The DA-26 is not hybrid, it's full tube. The MT-604 is hybrid.
u mean TA- 26
if so do u see any big difference in balance and unbalance in tube world?
 

HarmonicTHD

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in layman terms ur saying that this tubes are half class_A amp right?
if so what other tube amp would recommend for warm and large sound stage.
Why would a tube amp be “warm” (second order harmonic distortions?, non flat frequency response?) or exhibit a “large soundstage”?

Please nothing wrong if one likes tube amps for whatever reason.
But most likely you are still a victim of some audio myths, which are technically unfounded and solely based on subjective / biased listening impressions of individuals (reviewers) without any scientific approach (eg. controlled ABX Tests). Those so-called reviews are unfortunately still plentiful and this forum aims to distinguish between facts and myths.

Or is there any hard data (for the amps you mentioned) which would support the characteristics you are after?

If not maybe you are open to consider the alternatives which are favorably reviewed here?
 
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Robin L

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in layman terms ur saying that this tubes are half class_A amp right?
if so what other tube amp would recommend for warm and large sound stage.
"Tube" gear covers a very wide range of audio gear including headphone amplifiers. By way of example---for many years I had STAX earspeakers with a Stax SRM-T1 amp. It was an amp with J-Fets driving a direct coupled tube output, that is to say no transformers in the design's output or signal path. It had a fractionally "warmer" sound than Stax' slightly less expensive transistor Energizer/Amp. At one point tried out my Earspeakers (as Stax called them) using an energizer without an amp that was attached to a Marantz 8b (all tube with output transformers). It was decidedly less focused in sound, close to muddy in the lower registers and rolled off in the treble. Different? Yes. Better? Decidedly not.


I have also used tube gear in many other ways. I don't want tube gear anymore. Usually the inclusion of tubes in the signal path reduces the level of audible detail.

I'd say the illusion of a "soundstage" has much more to do with the headphones themselves.

Right now I'm using the Topping L30 as a headphone amp. I prefer the sound of various open back Sennheiser headphones, in particular the Drop 6XX (the most precise and neutral) and the HD 579 (best projection of vocals). The Drop 6XX headphones are essentially the same as the Sennheiser HD 650 headphones. I'd say that headphones themselves have more to do with the illusion of a soundstage. My Philips Fidelio X2HRs have the widest soundstage, but are somewhat nasty in the treble range. The open back Sennheisers that I have owned and used do not have as wide a soundstage but have much better treble.




Ya pays yer money and you makes yer choices. My choice is Drop 6XX/Topping L30 combo, though there are obviously many other options out there. This combo has the most focused sound, albeit with a smaller sense of sound stage than other combos I've owned. This combo is the most detailed without ever being artificially harsh in the upper registers.

While this doesn't answer your question, it should give you some idea of the variables. Tubes can "warm" up the sound or make it "muddier" depending on the auditioner. But soundstage has a lot more to do with the headphones themselves.
 
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Robin L

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Tubes will not, in general, give you a "warm" sound, except in your imagination. They are fashion statements.

If "warm" is what you want, use EQ.
Or Sennheiser open back headphones, which usually have artificial "warmth" in their sound without EQ.
 

ftv

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Or Sennheiser open back headphones, which usually have artificial "warmth" in their sound without EQ.
Not to hijack this thread, but do you know what gives them that artificial warmth (bump in the mid range?), and how can I add that to more neutral headphones? Just bought the Utopia and while better in every aspect than my old Sennheiser HD585(?) on paper, it does not quite elicit the emotional response to vocals that the Sennheiser provided. Thought of getting a tube amp and/or something like the Schiit Lokius or Loki Max to fix that.
 

DVDdoug

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Not to hijack this thread, but do you know what gives them that artificial warmth (bump in the mid range?)
I used to think "warm" meant a boost in the upper-bass range, but to some people it means slight "desirable" distortion. So I usually try to avoid this kind of terminology, or like you, explain exactly what I'm talking about.

A headphone's frequency response is determined by its electro-mechanical and physical properties. I don't know exactly what contributes to the midrange or mid-bass bump. It's obviously not "easy" to make a headphone with flat frequency response, or one that tracks the Harmon preference curve, but it's also obviously not super-expensive.

and how can I add that to more neutral headphones?
You can tweak the frequency response with equalization. There are software & hardware equalizers.

You have to be a bit careful with boosting because you can drive the amplifier or headphones into distortion (especially if you are already listening "loud"). Or with digital EQ you can push the digital levels into digital clipping although most software equalizers have a volume/gain adjustment to lower the overall level.

Thought of getting a tube amp and/or something like the Schiit Lokius or Loki Max to fix that.
Probably not...

If your headphone amp has a high output impedance, the frequency response of your headphones will be altered... A bump in headphone-impedance at a certain frequency will make a bump in frequency response at that same frequency. (Headphones are tested & specified with a low-impedance "constant voltage" source.) It's all relative and it happens to a lesser extent with high impedance headphones and it doesn't happen at all with a good headphone amp, which will have low output impedance.*

If the headphone amp has high output impedance and the headphone has a bump in impedance in the mid-bass range that might work. Some people get that effect and they like it. But, the headphones probably have other impedance variations and you probably won't get the "right amount" of boost at the "right frequency". (Technically, it's not "boost"... It's a drop where the impedance is lower but it's a relative boost where the headphone impedance is higher.)

Tubes to tend to have higher impedance than solid state electronics but in a hybrid amp the tube probably isn't at the output stage driving the headphones. With tube power amplifiers (for driving speakers) the audio goes-through an impedance-matching transformer between the tubes & speaker. The transformer can potentially add its own distortion and frequency response variations in addition to any potential tube distortion. I don't know if any "modern" tube headphone amps have a transformer.



* You don't normally get a published output-impedance spec. Usually they give you the recommended minimum headphone impedance. The amp's impedance should be much lower.
 

Katji

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Not to hijack this thread, but do you know what gives them that artificial warmth (bump in the mid range?), and how can I add that to more neutral headphones? Just bought the Utopia and while better in every aspect than my old Sennheiser HD585(?) on paper, it does not quite elicit the emotional response to vocals that the Sennheiser provided. Thought of getting a tube amp and/or something like the Schiit Lokius or Loki Max to fix that.
If the source is Windows PC, you can do EQ quite easily with nice free software Equalizer APO. Boost the dB over the voice frequency band by dragging points on the graphical display or by increasing the dB number with up/down arrows or typing a higher number. And hear the difference in 1 second. Like you could boost that entire band or just the middle of it, then when that sounds more like what you want, adjust up/down just the higher or lower ends of the range, and see how that affects it. And then you can go on to refine it further. Rather thn buying and trying various tube or hybrid tube amps and hoping it will have the effect you want. Although as per DVDdoug's reply, there can be more to it than just EQ.

crop of screenshot showing 32 band graphic equalizer:

1656697499503.png

you can make it simpler by using 15 band:

1656697676063.png
 
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Robin L

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Not to hijack this thread, but do you know what gives them that artificial warmth (bump in the mid range?), and how can I add that to more neutral headphones? Just bought the Utopia and while better in every aspect than my old Sennheiser HD585(?) on paper, it does not quite elicit the emotional response to vocals that the Sennheiser provided. Thought of getting a tube amp and/or something like the Schiit Lokius or Loki Max to fix that.
What DVDDoug sez. I actually eq that upper bass/lower midrange so as to cut between 100hz to 300hz.
 

ftv

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So equalization may do the trick if I interpret this correctly, which is fine if using a PC but honestly after working on computers for almost 40 years now the last thing I want to do is mess around with yet another piece of software when the idea is to relax and enjoy the music.
Some have mentioned that Roon has the ability to apply EQ, and if that is configurable and easy to use (once set up), that's a consideration, though that implies that all streamed music is source (Qobuz, Tidal, etc) to Roon core(?) to streamer which adds yet another hop. Why would devices like Schiit EQs or an RME DAC/amp not work, albeit at lesser precision? They do have the advantage of working with all sources including CD players and turntables.
 

Katji

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yes, the RME would be easier, simpler. I only listen to music on computer, 90% while using the computer...the only thing that changed in the last 30_ years is that now it's only laptop. iow, I don't sit or lie and stare into space, I do that in front of the tv.
 

Ja1man

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Why would a tube amp be “warm” (second order harmonic distortions?, non flat frequency response?) or exhibit a “large soundstage”?

Please nothing wrong if one likes tube amps for whatever reason.
But most likely you are still a victim of some audio myths, which are technically unfounded and solely based on subjective / biased listening impressions of individuals (reviewers) without any scientific approach (eg. controlled ABX Tests). Those so-called reviews are unfortunately still plentiful and this forum aims to distinguish between facts and myths.

Or is there any hard data (for the amps you mentioned) which would support the characteristics you are after?

If not maybe you are open to consider the alternatives which are favorably reviewed here?
Even order harmonic distortions are sometimes added to mixes for a feeling of heft to notes and odd order harmonic distortions are added for grit. Even order are considered more natural, these are what is given out by Single Ended Triode amps. The second order harmonics apparently give music presence.
 

SIY

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Even order harmonic distortions are sometimes added to mixes for a feeling of heft to notes and odd order harmonic distortions are added for grit. Even order are considered more natural, these are what is given out by Single Ended Triode amps. The second order harmonics apparently give music presence.
Where did you read this?
 
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