[hmscott]

I came across that a while back when I was deciding on MT-602 or MT-604.

Nice, thank you for catching that and speaking up, it is nice to know that Xduoo has developed and produced a Tube Pre-amplifier.

@PetFju

Someone on Head-fi is using an Xduoo MT-603 Pre-amplifier:
https://www.head-fi.org/threads/schiit-lokius-impressions-reviews.958856/post-16609749
https://www.head-fi.org/threads/schiit-lokius-impressions-reviews.958856/post-16609854

 

[Shane D]

Nice, thank you for catching that and speaking up, it is nice to know that Xduoo has developed and producted a Tube Pre-amplifier.

And, someone on Head-fi is using an Xduoo MT-603 Pre-amplifier:
https://www.head-fi.org/threads/schiit-lokius-impressions-reviews.958856/post-16609854

My amp (MT-602) states that the line out can be used as a pre-amp. Is that what you are looking for? Or something different?

 

[hmscott]

My amp (MT-602) states that the line out can be used as a pre-amp. Is that what you are looking for? Or something different?

Then the MT-602 output can operate like the TA-26 output as a tube buffer gain stage with volume control, but they are missing a source switcher functionality.

I think of a preamplifier as including both an active gain stage, volume control, and a source switcher, which the MT-603 preamplifier does - it has 4 inputs to one output along with an active gain stage with volume control.

Then there are Phono Pre-Amplifiers, they act as a gain stage, and sometimes include "switching" between Moving Coil and Moving Magnet matching and amplification characteristics, but are usually dedicated to one source device. They may have switchable settings for gain, but typically they don't have a variable volume control.

All just words trying to reign in the description for the function of a device, no matter the words the device can do what it is physically able to do. Humans need the words of description, the devices don't care.

 

[PetFju]

@Shane D @hmscott Thank you guys! That will be just about what the doctor ordered (and soon me i suppose)
Now the question is; will the sound quality of the MT-603 equal that of the TA-26 as a pre..we shall see! Also, this gives so many opportunities as far as different "power-amps" go. The Atrox V2 that i have now has got to be one of the more powerful and sweet sounding class A amps out there for cans, at least at that pricepoint, but its design is a bit dated, and its looks are not gonna win any beauty contests either. Not that THAT matters so much though, but it's part of the total.
Now i wish that Topping (or xDuoo for that matter) made a simple power-amp with no volume control. Anyways, as soon as i find where i want to order from i will get that MT-603, so thank you guys for pointing that out, i didn't know that one existed, even after looking at xDuoo's web page.

 

[hmscott]

@Shane D @hmscott Thank you guys! That will be just about what the doctor ordered (and soon me i suppose)
Now the question is; will the sound quality of the MT-603 equal that of the TA-26 as a pre..we shall see! Also, this gives so many opportunities as far as different "power-amps" go. The Atrox V2 that i have now has got to be one of the more powerful and sweet sounding class A amps out there for cans, at least at that pricepoint, but its design is a bit dated, and its looks are not gonna win any beauty contests either. Not that THAT matters so much though, but it's part of the total.
Now i wish that Topping (or xDuoo for that matter) made a simple power-amp with no volume control. Anyways, as soon as i find where i want to order from i will get that MT-603, so thank you guys for pointing that out, i didn't know that one existed, even after looking at xDuoo's web page.

Well, as far as sound quality, you'll have to get one and let us know which tubes sound best.

It is nice that the MT-603 only has 1 tube, so you can get 2x the variety of tubes to try!

Topping has some amps:
https://www.tpdz.net/amplifier

With their new PA5 the new hotness:
https://www.tpdz.net/productinfo/737898.html

The MT-603 uses a single 12AU7, but I wonder if it will support 12AT7 and 12AX7? service@xduoo.net might know

 

[PetFju]

Well, as far as sound quality, you'll have to get one and let us know which tubes sound best.

I Will let you know It'll take a little while yet, but it'll be interesting to see.

It is nice that the MT-603 only has 1 tube, so you can get 2x the variety of tubes to try!

Yea. I already have quite a few different 12AU7's from the TA-20, so a lot to try

Topping has some amps:
https://www.tpdz.net/amplifier

With their new PA5 the new hotness:
https://www.tpdz.net/productinfo/737898.html

I's have to get a special cable made with the speaker plugs on the amp end. Also, how about output impedance? That part is a bit over my head so to speak, but will it work well do you think?

The MT-603 uses a single 12AU7, but I wonder if it will support 12AT7 and 12AX7? service@xduoo.net might know

I'll find out

 

[hmscott]

I Will let you know It'll take a little while yet, but it'll be interesting to see.

Yea. I already have quite a few different 12AU7's from the TA-20, so a lot to try

I's have to get a special cable made with the speaker plugs on the amp end. Also, how about output impedance? That part is a bit over my head so to speak, but will it work well do you think?

I'll find out

Yeah, due to the tiny case size - creating the need for a huge external power brick - the PA5 doesn't have enough case size for connectors, so custom cables are available from Topping too, isn't that nice of them:
https://www.tpdz.net/others

The PA5 is a Class D amplifier, a different design that doesn't need banks of large capacitors or a large transformer, so most of these Class D amps are sold as boards with others combining the amp board with a power supply, box, and measurements - all it takes to become an amplifier builder these days

There are a lot of people that swear by the Class D design, but I've not heard one. That is why I haven't bought one, I'd need to hear a new Class Amp's sound first, on headphones. That and the PA5 has too much power, but has great measurements, the previous PA3 didn't have great measurements nor quite enough power. I'm still looking for an amp to drive the HE6SE V2 - with the TA-26 I've found the amp for 600 ohm headphones.

The MT-603 looks like good fun

This post/thread has some links of interest, and before (after?) photo's of the PA5 inside:

Topping PA5 (TPA325X) : Is a modification worth it? ?
https://www.diyaudio.com/community/threads/topping-pa5-tpa325x-is-a-modification-worth-it.380233/

 

[PetFju]

I got the little tube dampeners today. I have to say they actually help a little as far as noise goes.
So the tubes still will make a racket if i tap them, but now the volume wheel doesn't make the sound crackle any more. So yey

Semi OT: I received the Sennheiser HD560 in the mail today, and have been trying them out on different amps. They work just fine with the TA-26, even at their 120ohms, so that's a good thing!
Other than that i have to say i (for the most part) like the sound of the HD560 better then the 58X. Other than for acoustic and "singer songwriter" type music, and Maybe EDM, they're much more balanced. Good budget cans for sure! Also as a bonus they are great for gaming

Edit; Also i see i need to be dusting again..It becomes so evident in pictures with that kind of lighting lol

 

[albertmuc]

Received my „xDuoo TA-20“ today, unpacked it and was amazed at the flawless quality of the workmanship. If Sony had been listed as the manufacturer instead of xDuoo, I would have believed it. A short function check with the standard tubes, then a pair of matched "Gold Lion 12AU7 / ECC82 Genalex" installed. The xDuoo is my first headphone tube amplifier, so I was curious what to expect. I'm hooked from the first bars, it sounds like I can hear the music through a magnifying glass, and much fuller, sweeter, amazing. In combination with my LCD-X, the „TA-20“ is an asset that belies the purchase price. Let's hear where the tube develops in terms of sound. Anyway, I already realize: it is possible to listen without a tube, but it is a waste of life time!


Question’s:

The headphones should be plugged in and unplugged when the volume control is at 0.
Turn on the amp before plug in the headphones.
Before switching off, unplug the headphones. All right?

The xDuoo is balanced connected to the RME. The settings on the RME are:

"Auto Ref Level = off"
&
"Ref Level = + 7 dBu"
&
"Volume 0 dB"

With the previous RME settings, I listen to the xDuoo with a volume setting of 55-60. Is there something to optimize?

 

[PetFju]

Received my „xDuoo TA-20“ today, unpacked it and was amazed at the flawless quality of the workmanship. If Sony had been listed as the manufacturer instead of xDuoo, I would have believed it. A short function check with the standard tubes, then a pair of matched "Gold Lion 12AU7 / ECC82 Genalex" installed. The xDuoo is my first headphone tube amplifier, so I was curious what to expect. I'm hooked from the first bars, it sounds like I can hear the music through a magnifying glass, and much fuller, sweeter, amazing. In combination with my LCD-X, the „TA-20“ is an asset that belies the purchase price. Let's hear where the tube develops in terms of sound. Anyway, I already realize: it is possible to listen without a tube, but it is a waste of life time!

Congrats on a great amp! It's really a great value, for sure

Question’s:

The headphones should be plugged in and unplugged when the volume control is at 0.
Turn on the amp before plug in the headphones.
Before switching off, unplug the headphones. All right?

I honestly don't mind any of that. This amp is "easy street" to me; connect, disconnect, turn on or off, doesn't matter it seems. My way might wear on the amp after a while, but it certainly won't kill it. And if any of the aforementioned behaviour would be damaging to the amp it really should be clearly stated and labeled on the amp, true "Murica-style"

The xDuoo is balanced connected to the RME. The settings on the RME are:

"Auto Ref Level = off"
&
"Ref Level = + 7 dBu"
&
"Volume 0 dB"

With the previous RME settings, I listen to the xDuoo with a volume setting of 55-60. Is there something to optimize?

I find that having my RME on +7 and from there turning it down to 0 gives headroom for eq in a better way as to not overdive. Same goes for the use of the loudness, if you utilize that. However normally i just keep it at +1 and call it a day, no eq.
Depending on the connected headphones that would run my TA-20 between 65 and 80 for comfortable to loud listening levels.
BTW; if you upgrade the firmware on the RME you get new colorschemes for the VU, as well as an auto-DC cutoff. The DC-cutoff has saved my ass a couple of times playing random tracks on spotify actually, so it's a useful feature.

 

[albertmuc]

…I honestly don't mind any of that. This amp is "easy street" to me; connect, disconnect, turn on or off, doesn't matter it seems. My way might wear on the amp after a while, but it certainly won't kill it. And if any of the aforementioned behaviour would be damaging to the amp it really should be clearly stated and labeled on the amp, true "Murica-style"…

I'm less worried about the amp than about the Audeze headphones, because they don't like plop's…

 

[PetFju]

I'm less worried about the amp than about the Audeze headphones, because they don't like plop's…

Obviously turn the volume down.. Anyways, take care if you swap headphones and such as far as different sensitivity etc.
I haven't noticed any bad "plops" with the TA-20 though, but that is my experience and you may not be as lucky..

 

[albertmuc]

Plugged the T1.3 into the TA-20 with low expectations. Low expectations, because the Beyerdynamic already sounds warm and bassy. To my surprise, the Beyerdynamic wins enormously, especially through a plastic image and more beautiful voices.

 

[jonathan c]

Plugged the T1.3 into the TA-20 with low expectations. Low expectations, because the Beyerdynamic already sounds warm and bassy. To my surprise, the Beyerdynamic wins enormously, especially through a plastic image and more beautiful voices. The T1.3 seems made for tubes (at least for the TA-20), despite being only 32 ohms, strange but true.

It may actually be less strange than you think. The output stage of the TA-20 is solid-state operating in class A. The output impedance (though not stated), therefore, is likely to be very low (1 ohm or less). The T1.3 headphones at 32 ohms would be well controlled by the TA-20. [The ‘damping factor’ would be 32.]

 

[albertmuc]

It may actually be less strange than you think. The output stage of the TA-20 is solid-state operating in class A. The output impedance (though not stated), therefore, is likely to be very low (1 ohm or less). The T1.3 headphones at 32 ohms would be well controlled by the TA-20. [The ‘damping factor’ would be 32.]

Control is also provided via the RME, thanks to an equally low output impedance. But over the TA-20, the T1.3 doesn't get too much bass, or too much warmth, I would have expected something like that, the T1.3 only wins!

Suffice to say, those who haven't heard the T1.3 through a matching tube amp haven't heard the T1.3 at all. Admittedly I've only heard the T1.3 on the RME, not on the more powerful SS, but the jump through the TA-20 is just massive.