Acoustic portrait Swara Tube buffer V2 (A review)

[Shammi Dang]

A review after more than a month of usage - This is my first Acoustic portrait product. I purchased this on total risk as there were no reviews (video or written) available anywhere. I am very satisfied with this tube buffer. It adds warmth to the vocals and music. Very nice to hear such depth and wide soundstage. No listening fatigue. Very appropriate for listening to classical (Indian, western), pop, vocals, hindi songs & gazals. The slight harness that we feel sometimes while using our regular transistor based amplifier is not there any more. Excellent built quality, Good fit & finish, Solid chassis, subtle & simple looks. One more point to mention is the excellent packaging done by the company and there was no problem with the deliveries. I have purchased this from Hifi mart but the deliveries were initiated directly from the company based in Bangalore. I have attached this in between the DAC (Schiit modi 3) and integrated amplifier (Norge Concerto Gold 1000 class AB) and most of my music sources are routed through this Dac.

Some nick picking - Very heavy in weight and big size for a tube buffer, The embossed logo on the front can be little brighter, it looks dull and not properly visible. The bypass is not there, in case connected between two lines then it must be "ON" to pass the signal. Heats up a little, I think that's the characteristic of tubes so it requires good ventilation. The dynamism of the amplifier is mellowed down slightly because of warm tonal signature so we have to open little more volume to arrive at a comfortable listening level.

Overall it is a recommended product for anyone who wants to add the warmth and signature of tube sound to their solid state set up at a reasonable cost. There are some cheaper options available on amazon by some chinese brands (branded & generic) but I really doubt those will be able to match the quality of this tube buffer.

 

[alpha1]

I wonder is there a quantifiable property (or properties) that explain the harshness and warmth in audio?
Ultimately all acoustic signal (sound waves) reaches our ears, whichever way they may be produced/processed, and the usual properties associated with such a signal (compression wave propagating using air molecules) is amplitude, frequency, time/phase, ...

 

[Shammi Dang]

I wonder is there a quantifiable property (or properties) that explain the harshness and warmth in audio?
Ultimately all acoustic signal (sound waves) reaches our ears, whichever way they may be produced/processed, and the usual properties associated with such a signal (compression wave propagating using air molecules) is amplitude, frequency, time/phase, ...

Human ears, everyone perceives things differently. In reality there is nothing good or bad, superior or inferior, it is just how we feel and portray our opinions/emotions/feelings.
And this is a super quote in your reply , I really liked it - When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion.

 

[ajuvignesh]

I wonder is there a quantifiable property (or properties) that explain the harshness and warmth in audio?
Ultimately all acoustic signal (sound waves) reaches our ears, whichever way they may be produced/processed, and the usual properties associated with such a signal (compression wave propagating using air molecules) is amplitude, frequency, time/phase, ...

In fact, two. Less treble makes the sound warm. Tube adds even harmonics to the chain, and that makes the sound a bit more musical. Harshness is due to odd harmonics, unrefined treble, digital glare, etc.

 

[alpha1]

Human ears, everyone perceives things differently. In reality there is nothing good or bad, superior or inferior, it is just how we feel and portray our opinions/emotions/feelings.
And this is a super quote in your reply , I really liked it - When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion.

Of course, preferences will vary, and someone may like the sound the others may hate it (refer the below section of my post).
But unless it is measurable it remains arbitrarily defined and subject to misuse and abuse - today I will feel certain amp is warm, tomorrow I will feel the same amp with exact same setup as cold, in which case there is no meaning to any audio review other than simple reading pleasure!

In fact, two. Less treble makes the sound warm. Tube adds even harmonics to the chain, and that makes the sound a bit more musical. Harshness is due to odd harmonics, unrefined treble, digital glare, etc.

Shouldn't that be easily replicable on non-Valve amps?
I remember a plugin in f00bar media player that could introduce odd/even harmonics at will.
I remember it helping the bass frequencies sound deep but everything else sounded like hearing a clean radio AM reception (= perceptible underlying static and giving a low-fi feel).

 

[mbhangui]

Of course, preferences will vary, and someone may like the sound the others may hate it (refer the below section of my post).
But unless it is measurable it remains arbitrarily defined and subject to misuse and abuse - today I will feel certain amp is warm, tomorrow I will feel the same amp with exact same setup as cold, in which case there is no meaning to any audio review other than simple reading pleasure!

Very true. I for one don't like the sound from my tube amp, even though my first real amp was a tube amp. Soon outgrew it and I prefer my Class D amps and even my Yamaha AVR over the tube amp. The tube amp I have doesn't have the treble that I look for.

Vintage amps always had the bass and treble control and that was a good thing because it allowed you to tune the amp to your liking.

Shouldn't that be easily replicable on non-Valve amps?
I remember a plugin in f00bar media player that could introduce odd/even harmonics at will.
I remember it helping the bass frequencies sound deep but everything else sounded like hearing a clean radio AM reception (= perceptible underlying static and giving a low-fi feel).

Exactly. I have seen hardware versions of harmonic generator on diyaudio. The focusrite dac that I got came with software which allows you to do these things using my macbook/macmini. But mac osx has other issues (like fixed sampling rates) due to which I use only Linux boxes for digital music playback.

For my main system I use an ancient Kenwood GE-850 parametric equalizer, output of which goes to a DIY Nelson Pass B1 buffer. The output of that goes to a DIY Elliot's designed preamp (box with wooden face plate). The Elliot's preamp has a self designed switcher that allows me to chose to which amp the output should go. For headphone listening I use DBX 231s 31 band equalizer. which is below this image

 

[ajuvignesh]

Of course, preferences will vary, and someone may like the sound the others may hate it (refer the below section of my post).
But unless it is measurable it remains arbitrarily defined and subject to misuse and abuse - today I will feel certain amp is warm, tomorrow I will feel the same amp with exact same setup as cold, in which case there is no meaning to any audio review other than simple reading pleasure!


Shouldn't that be easily replicable on non-Valve amps?
I remember a plugin in f00bar media player that could introduce odd/even harmonics at will.
I remember it helping the bass frequencies sound deep but everything else sounded like hearing a clean radio AM reception (= perceptible underlying static and giving a low-fi feel).

I guess it is possible. Sugden A21 is a solid state amp but sounds tube like.

 

[COOLDUDE7808]

@Shammi Dang - AP Tube Buffer sort of reduces the treble which Norge 1000 produces . I am reminded of what Laxman said during the demo , He played Norge MOSFET Reference 2000 Stereo Amplifier and told me Mosfet amps have a warm sound , so you will not feel irritated /angry when you listen to music for a long time . To my ears in that setup - that was not very lively

When I pair Norge with CD 5001 its sounds great . When paired with CD 6005 it does sound bright sometimes . If you are using AP with multiple gears then I guess its worth it . I think you are trying get Warm NAD sound out of Norge .

After purchasing Norge when I look at prices of other gears - Its like for 30K you can get one more Norge Amp .

Since we are in HIFIVISION I also liked the quote - When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called audiophile community

 

[alpha1]

@Shammi Dang - AP Tube Buffer sort of reduces the treble which Norge 1000 produces . I am reminded of what Laxman said during the demo , He played Norge MOSFET Reference 2000 Stereo Amplifier and told me Mosfet amps have a warm sound , so you will not feel irritated /angry when you listen to music for a long time . To my ears in that setup - that was not very lively

When I pair Norge with CD 5001 its sounds great . When paired with CD 6005 it does sound bright sometimes . If you are using AP with multiple gears then I guess its worth it . I think you are trying get Warm NAD sound out of Norge .

After purchasing Norge when I look at prices of other gears - Its like for 30K you can get one more Norge Amp .

Since we are in HIFIVISION I also liked the quote - When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called audiophile community

From the webpage:
Norge Concerto Gold 1000
Output 100w + 100w rms @ 4 ohms / 92w + 92w rms @ 8 ohms
Freq. Response 30Hz-20kHz +/- 0.5db
THD @ rated output < 0.075%
Input Sensitivity 92 db

Norge MOSFET Reference 2000 Stereo Amplifier
Output 100w + 100w @ 4 ohms / 90w + 90w @ 8 ohms
Freq. Response 35Hz-20kHz +/- 0.5db
THD @ rated output < 0.04% @ rated output
S.N. Ratio 92 db

 

[Shammi Dang]

@Shammi Dang - AP Tube Buffer sort of reduces the treble which Norge 1000 produces . I am reminded of what Laxman said during the demo , He played Norge MOSFET Reference 2000 Stereo Amplifier and told me Mosfet amps have a warm sound , so you will not feel irritated /angry when you listen to music for a long time . To my ears in that setup - that was not very lively

When I pair Norge with CD 5001 its sounds great . When paired with CD 6005 it does sound bright sometimes . If you are using AP with multiple gears then I guess its worth it . I think you are trying get Warm NAD sound out of Norge .

After purchasing Norge when I look at prices of other gears - Its like for 30K you can get one more Norge Amp .

Since we are in HIFIVISION I also liked the quote - When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called audiophile community

Yes, I do agree it reduces treble a wee bit. As such before attaching the tube buffer I used to reduce the treble a little below half. Now I keep it at half exact. I am mostly using wharfedale evo 4.1 speakers and with these I do not feel any treble loss. I also use another amplifier, a cambridge audio am10 without the tube buffer that is direct connection from the DAC/other source. I have a Fosi audio LC30 switcher where I can use any of the amps with the same speakers. The concerto gold 1000 is different in it's tonal presentation in comparison to the MOSFET 2000. However I do agree with some of the points u have mentioned in ur observation. I have kept my system flexible enough so to use the tube buffer or with just a simple switch of a cable I can use the Norge amp directly. Thanks for ur input and observations.