NFJ&FX Audio Tube-03 - Tube Pre Amplifier

amrutmhatre90

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I came across this super cheap Tube Amplifier on Amazon, always wanted to listen how these tube amps sound.
Bit the bullet and ordered this.


Now some say this is a Tube Pre Amp some call it Tube Buffer, what I was looking was to add my own personal coloration to the sound when I wanted to.
Heard Tubes sound warm, I would like it that way, but a tone control on this opens up more options.

Now my Gear is Denon x3700 connected to Crown XLS 2002 powering Taga 606v3 Floorstanding speakers. I love the way they sound for music as well as movies.
For Music I have a Preset which keeps fronts as Large and turns Audyssey off, Stereo Mode enough punch but slightly on brighter side.
I mostly listen through Tidal HEOs App or sometimes Alexa Echo Dot.

Recently I acquired a Activo CT10 using it to play hi res and MQA on the go and use as a streamer plan is to connect this to the Tube Pre Amplifier.
Had 2 Paths in mind will look something like this,
1) Activo CT10 > Tube Preamp > AVR Line In like CD or AUX ( 90% using this)
2) Crown XLS > Tube Pre Amp > AVR Front Pre outs (This can spoil the perfect movie setup I am having now)

Which one from above will be a good path? any other paths or ways around this?

Wanted to know how to source Vaccum tubes, I got few links on Amazon but most of them are coming from outside India.
Any leads on Vaccum tubes or IC amplifiers or parts in Mumbai or source within India ?

Has anyone used this Tube Pre Amp before or something like this?
 

DB1989

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Recently I acquired a Activo CT10 using it to play hi res and MQA on the go and use as a streamer plan is to connect this to the Tube Pre Amplifier.
Had 2 Paths in mind will look something like this,
1) Activo CT10 > Tube Preamp > AVR Line In like CD or AUX ( 90% using this)
2) Crown XLS > Tube Pre Amp > AVR Front Pre outs (This can spoil the perfect movie setup I am having now)

Which one from above will be a good path? any other paths or ways around this?

Wanted to know how to source Vaccum tubes, I got few links on Amazon but most of them are coming from outside India.
Any leads on Vaccum tubes or IC amplifiers or parts in Mumbai or source within India ?

Has anyone used this Tube Pre Amp before or something like this?
You mean AVR Front Pre outs > Tube Pre Amp > Crown XLS I assume.

The first config is the way to go. I have the same tube buffer. Adds a bit of warmth to the sound with the stick tubes but they do not sound clean and the bass is bloated. Get GE tubes which tone down the warmth quite a bit compared to the stock ones but relatively still more full bodied sound than if there was no tube preamp and but the sound is becomes much more cleaner.
 

amrutmhatre90

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You mean AVR Front Pre outs > Tube Pre Amp > Crown XLS I assume.

The first config is the way to go. I have the same tube buffer. Adds a bit of warmth to the sound with the stick tubes but they do not sound clean and the bass is bloated. Get GE tubes which tone down the warmth quite a bit compared to the stock ones but relatively still more full bodied sound than if there was no tube preamp and but the sound is becomes much more cleaner.

Yes my bad, your right.
Can you tell me how to source the GE tubes ? have you tried changing the IC amp too ?

Can you post picture and how have you geared it ? new to all this.
 

greenhorn

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+1 to the above. If you think the ge tubes are pricey, there are russian equivalents which are cheaper and are better than the Chinese and have 95% of the ge sound.

I don't have a fixed config. I use it in between any digital source and amp. (Which I've been playing around with to find different configs)
 

amrutmhatre90

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I am able to find the GE tubes on Amazon only, any leads to other tubes would also work out.
But need authentic and real ones, lots of fake stuff out their.
 

ssf

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I came across this super cheap Tube Amplifier on Amazon, always wanted to listen how these tube amps sound.
Bit the bullet and ordered this.


Now some say this is a Tube Pre Amp some call it Tube Buffer, what I was looking was to add my own personal coloration to the sound when I wanted to.
Heard Tubes sound warm, I would like it that way, but a tone control on this opens up more options.

Now my Gear is Denon x3700 connected to Crown XLS 2002 powering Taga 606v3 Floorstanding speakers. I love the way they sound for music as well as movies.
For Music I have a Preset which keeps fronts as Large and turns Audyssey off, Stereo Mode enough punch but slightly on brighter side.
I mostly listen through Tidal HEOs App or sometimes Alexa Echo Dot.

Recently I acquired a Activo CT10 using it to play hi res and MQA on the go and use as a streamer plan is to connect this to the Tube Pre Amplifier.
Had 2 Paths in mind will look something like this,
1) Activo CT10 > Tube Preamp > AVR Line In like CD or AUX ( 90% using this)
2) Crown XLS > Tube Pre Amp > AVR Front Pre outs (This can spoil the perfect movie setup I am having now)

Which one from above will be a good path? any other paths or ways around this?

Wanted to know how to source Vaccum tubes, I got few links on Amazon but most of them are coming from outside India.
Any leads on Vaccum tubes or IC amplifiers or parts in Mumbai or source within India ?

Has anyone used this Tube Pre Amp before or something like this?
You could also try Activo CT10 > Tube Preamp - > Crown without the Denon AVR in the chain. You will just need a pair of additional interconnects which you can change at the crown side. This will be a pre-power setup for music.

Just to see the difference, you could also connect the Activo CT10 directly to the crown if CT10 has volume controls.

I listen to music in 3 ways:

1. Marantz in pure direct.
2. Marantz + Crown in pure direct
3. Zen Dac -> FX Audio tube pre -> Crown xls 2502

A bit of cable swapping is required but fun to listen to different flavors of sound.

I have two pairs of these:
https://www.amazon.in/Riverstone-Audio-Matched-Fully-Tested-Replacement/dp/B01BFJDTW0
 
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adakadavuley

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FWIW I got a chinese tube preamp (looks just like the FX audio ones. I think they are all the same) to pair with the crown xls2002. I was not a fan of the distortion they added to the chain. I find the sound from the Crown to be cleaner and I prefer it. I feed it from a Digione and Topping E30. Trying some EQ could be better than adding a tube preamp to the chain I feel. I got the tube preamp because I felt the sound in my system was lacking something. I think it is more to do with my speakers than the amp.
 

Kannan

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It is basically a tube buffer with a little extra gain through a SS circuit. The OE tubes are not good and the sound will improve with tube rolling. The gain stage though is below average.
I would instead suggest a zero gain tube buffer like the Yaqin SD2 or SD3. Some cheaper Chinese iterations are also available
 

DB1989

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Yes my bad, your right.
Can you tell me how to source the GE tubes ? have you tried changing the IC amp too ?

Can you post picture and how have you geared it ? new to all this.
Will have to post multiple pics and it wont be clear as to how I’ve connected them. Plus, the back of the AV Rack with its tangle of wires is in need of a good and righteous cleaning. :rolleyes:

The chain is Allo USBridge Signature Player +Digione Signature (streamer)>Chord Mojo (DAC)>FX Audio DP03 (tube preamp)>Cambridge Audio CXA81 (amplifier)>Quad S5 (speakers)

the connection is going to pretty straightforward.

haven’t tried changing the IC amp.

the GE tubes were carried back by a friend from the US as they were ridiculously priced on amazon india.
 
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Yogesh

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Will have to post multiple pics and it wont be clear as to how I’ve connected them. Plus, the back of the AV Rack with its tangle of wires is in need of a good and righteous cleaning. :rolleyes:

The chain is Allo USBridge Signature Player +Digione Signature (streamer)>Chord Mojo (DAC)>FX Audio DP03 (tube preamp)>Cambridge Audio CXA81 (amplifier)>Quad S5 (speakers)

the connection is going to pretty straightforward.

haven’t tried changing the IC amp.

the GE tubes were carried back by a friend from the US as they were ridiculously priced on amazon india.
How much and what kind of difference does FX Audio DP03 make?
 

amrutmhatre90

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Thanks guys for the suggestions, won't be removing the Crowns from AVR. As I am totally satisfied with the sound i get from them while 2ch listening music or movies.
Instead will keep the Tube Pre amp on aux and use it when I need to listen tube sound.

I am trying to find the Vaccum tubes in Mumbai, got one shop in Lamington. He is Checking if they have one.

Will keep you guys updated on the build.
 

ssf

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Thanks guys for the suggestions, won't be removing the Crowns from AVR. As I am totally satisfied with the sound i get from them while 2ch listening music or movies.
Instead will keep the Tube Pre amp on aux and use it when I need to listen tube sound.

I am trying to find the Vaccum tubes in Mumbai, got one shop in Lamington. He is Checking if they have one.

Will keep you guys updated on the build.
I would suggest that you try the connection without the Denon in the chain at least once. I see quite a difference between the two.
 

amrutmhatre90

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Yes sure, i do keep fiddling with setups.
Surely try it once.

I was going to try a integrated amp before ending up on tube pre amps, tube amps are cheap and they look cool too.

I would suggest that you try the connection without the Denon in the chain at least once. I see quite a difference between the two.

Found a shop in Mumbai which sells 5654 Vaccum tubes for 700 each.

Is there anything I should check particularly while buying the tubes?
 

fLUX

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Yes sure, i do keep fiddling with setups.
Surely try it once.

I was going to try a integrated amp before ending up on tube pre amps, tube amps are cheap and they look cool too.



Found a shop in Mumbai which sells 5654 Vaccum tubes for 700 each.

Is there anything I should check particularly while buying the tubes?

As suggested for stereo listening try using your ct10 as source and use the tube pre and crown.

Also while buying replacement tubes go for well known makes in.the model, you will notice good difference. Also buy gain matched tubes if you need a pair.
 

Yogesh

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It is basically a tube buffer with a little extra gain through a SS circuit. The OE tubes are not good and the sound will improve with tube rolling. The gain stage though is below average.
I would instead suggest a zero gain tube buffer like the Yaqin SD2 or SD3. Some cheaper Chinese iterations are also available
Have you had any experience with Yaqin CD 03? How much and what kind of difference does it make?
 

ssf

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How much and what kind of difference does FX Audio DP03 make?
I have a FX Audio DP-02 tube preamp wit GE 5654W tubes. To my ears, it makes the sound a bit laid back and the mids a bit thicker. A good match for my Crown amp.

Takes out the Airy treble of the Quad S2's just a bit though. A pleasant overall listen.
 
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