FX Audio 6j1 tube preamp - a $31 wonder

I am listening to the Svetlana svetlana 6ZH2P-EV right now (in the morning), Short impression, Sound good great speed, great bass , bass has less body than the mullard ef95, not too bright . I am happy with my budget system in my office right now amp + speaker >>>> fx audio tube 01 + pioneer VSX9900S (paid 90$ for it, sound not bad ) + TELLURIUM Q GREEN speaker cable (warm sounding speaker cable)+ Tannoy XTF8 (great speaker for theirs price , but have to aware of bass body (too much for a small room) and theirs brightness) >>> In addition, trying the RCA 6AK5 right now (in the evening), wowwww what a great tube. Its has everything, less bass body than the Mullard EF95, which suit my system more because both my speaker at home and at the office are both bass heavy speakers, The RCA has a better soundstage than the Mullard. real real great seperation between instruments. I think at the moment. I like it more than the Mullard (will try some more songs before my final verdict)

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butnotforme said:
I am listening to the Svetlana svetlana 6ZH2P-EV right now (in the morning), Short impression, Sound good great speed, great bass , bass has less body than the mullard ef95, not too bright . I am happy with my budget system in my office right now amp + speaker >>>> fx audio tube 01 + pioneer VSX9900S (paid 90$ for it, sound not bad ) + TELLURIUM Q GREEN speaker cable (warm sounding speaker cable)+ Tannoy XTF8 (great speaker for theirs price , but have to aware of bass body (too much for a small room) and theirs brightness) >>> In addition, trying the RCA 6AK5 right now (in the evening), wowwww what a great tube. Its has everything, less bass body than the Mullard EF95, which suit my system more because both my speaker at home and at the office are both bass heavy speakers, The RCA has a better soundstage than the Mullard. real real great seperation between instruments. I think at the moment. I like it more than the Mullard (will try some more songs before my final verdict)

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butnotforme said:
I am listening to the Svetlana svetlana 6ZH2P-EV right now (in the morning), Short impression, Sound good great speed, great bass , bass has less body than the mullard ef95, not too bright . I am happy with my budget system in my office right now amp + speaker >>>> fx audio tube 01 + pioneer VSX9900S (paid 90$ for it, sound not bad ) + TELLURIUM Q GREEN speaker cable (warm sounding speaker cable)+ Tannoy XTF8 (great speaker for theirs price , but have to aware of bass body (too much for a small room) and theirs brightness) >>> In addition, trying the RCA 6AK5 right now (in the evening), wowwww what a great tube. Its has everything, less bass body than the Mullard EF95, which suit my system more because both my speaker at home and at the office are both bass heavy speakers, The RCA has a better soundstage than the Mullard. real real great seperation between instruments. I think at the moment. I like it more than the Mullard (will try some more songs before my final verdict)

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Give those RCA's a chance to burn-in.
 
Yeah will do, Dr ears. I got these NOS, even out of the box they sound great. Thank for giving information about the RCA tube in those previous posts, that's made me want to try them out. Now I am waiting for the last tubes to come in the Voskhod 6zh1p-ev.
 
dajack761 said:
I received my Voskhod 6J1P-EV tubes today. How long should it take for them to burn in?
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I have no experience with them, but based on my experience with other Russian tubes, they start off hot, meaning too much gain, then start to calm down after 20 to 30 hours.

Your choice will come down to the RCA's or the Mullard's, which will likely be mood dependent.

The only tubes I like better than those are the Philips, Holland EF-95's, but I have loved made in Holland tubes for more than 20 years now, they feature a sweet warmth

My second tube buffer is loaded with a single ECC82 from the same plant in Holland as the EF-95's.

I still own hundreds of tubes, but only use three in my reference system, which is all I need.

There is an Ebay seller offering the Philips EF-95's at $39.95 each, but she hit a $50 bid for a pair + shipping, I bought two pairs and all tubes tested as high as possible!

My volume control is only set between 1/4 and 3/8 with these tubes, you will probably have to set the Russian tubes lower than that until and if they calm down.

I may bid on some Western Electric tubes that look like they are going to go cheaply on an Ebay auction, but you never know. Western Electric's are usually dead neutral.
 
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New guy here does anybody ever tried to used 6AU6 tube on FX-Audio tube 03?, from what I heard you need to jumper the pins to make it work
 
New member here also.
I have tube01 before but got fried coz I tried to power it with 15v adaptor. Was trying to fix it by bringing it to some electronic repairman, but unfortunately he couldn't fix it. So I decided to try tube03. Any hints on what parts should I change if I want to modified? What's the best caps, elco & opamp.
Thanks
 
Rakyat02 said:
New guy here does anybody ever tried to used 6AU6 tube on FX-Audio tube 03?, from what I heard you need to jumper the pins to make it work
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There is nothing special about 6AU6's, why bother?
There is a wide variety of plug and play tubes.
I just sniped a quad of Western Electric 403B's, which are a premium version of the 6AK5's, look for my review in a couple of weeks.
 
Be
Dr. Ears said:
There is nothing special about 6AU6's, why bother?
There is a wide variety of plug and play tubes.
I just sniped a quad of Western Electric 403B's, which are a premium version of the 6AK5's, look for my review in a couple of weeks.
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cause there's not a whole lot of variety of 6AK5 tubes in my country and there's no amazon or ebay here, the import tax is also high. The most readily available here area 6AU6, EF91 and EF92. so wondering can it be done.
 
carrots99 said:
I also have a doubt regarding the caps, since I've already seen someone saying we should replace the caps by others with the same capacitance and voltage, but on the other hand I already saw one user replacing the 4x 1uF 250V caps by 630V ones, where he mentions this way the ESR will be lower...also that japanese variant of the tube 03 has apparently 1.5uF caps instead of 1uF, so, is it better to keep the values, or put ones either with more voltage or more capacitance?!...

I was planning on replacing mine with the following (only found russian 160V and 250V caps, not 100V, so not sure about what impact it may have...):

https://www.ebay.com/itm/0-047uF-1u...Various-Russian/192887265127?var=493043887659
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160v or 250v variants are both completely fine from the standpoint of voltage.

I've been using the K42Y-2 for a longtime in many different audio circuits with great success, BUT getting them to fit can sometimes be a challenge.

Trying to get those 4 caps in that tiny space will be very difficult...


Rob43

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Rakyat02 said:
Be

cause there's not a whole lot of variety of 6AK5 tubes in my country and there's no amazon or ebay here, the import tax is also high. The most readily available here area 6AU6, EF91 and EF92. so wondering can it be done.
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They have different pin-outs and would require an adapter.
We are already not using these tubes as intended, they are RF sharp cut-off pentodes wired in triode mode!
Where are you located? Does the USPS deliver there?
 
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Dr. Ears said:
They have different pin-outs and would require an adapter.
We are already not using these tubes as intended, they are RF sharp cut-off pentodes wired in triode mode!
Where are you located? Does the USPS deliver there?
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No USPS doesn't deliver here. I'm located in Indonesia the only overseas shipping service that delivers here are FedEx and DHL but they charge a hefty tax for it
 
The reason I asked for this because from the Head Fi Little dot Tube rolling thread there's some success to it that some claim it sounds great though you are needed to do some tinkering to the pins. Also the problem with my country stock still persist.
 
Rakyat02 said:
The reason I asked for this because from the Head Fi Little dot Tube rolling thread there's some success to it that some claim it sounds great though you are needed to do some tinkering to the pins. Also the problem with my country stock still persist.
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From what I read substituting a 6AK5 for a 6AU6 improves the sound, meaning the other way it would not sound as good.
Does China deliver to Indonesia?
How much would it cost to have a $35 pair of tubes delivered there?
What piece of equipment are you putting them in?
If, an FX Audio, what happened to the original tubes?
The 6AU6's draw nearly twice the current of a 6AK5, 300ma's versus 175 and I don't know what effect that will have.
I honestly think, if a 6AU6 improved the sound over a 6AK5 the market would have discovered it by now.
The international prices of the two different tubes tells me that hasn't happened.
 
carrots99 said:
I also have a doubt regarding the caps, since I've already seen someone saying we should replace the caps by others with the same capacitance and voltage, but on the other hand I already saw one user replacing the 4x 1uF 250V caps by 630V ones, where he mentions this way the ESR will be lower...also that japanese variant of the tube 03 has apparently 1.5uF caps instead of 1uF, so, is it better to keep the values, or put ones either with more voltage or more capacitance?!...

I was planning on replacing mine with the following (only found russian 160V and 250V caps, not 100V, so not sure about what impact it may have...):

https://www.ebay.com/itm/0-047uF-1u...Various-Russian/192887265127?var=493043887659

Regarding tube rolling, today I just got a pair of Brimar CV4012 (6BE6W) tubes and they sound amazing, it's such a difference, bass is much deeper and to me the soundstage is also much wider (before I was using a pair of Voskhod 6J1P-EV)
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6BE6 can be used as it is without modding? is there any other series that can be done like so?
 
Performance curve charting predicts the performance of a tube under various operating cdx, the ideal is a linear relationship between input change vs output response.
Anything else is at best random guesswork.
 
Dr. Ears said:
From what I read substituting a 6AK5 for a 6AU6 improves the sound, meaning the other way it would not sound as good.
Does China deliver to Indonesia?
How much would it cost to have a $35 pair of tubes delivered there?
What piece of equipment are you putting them in?
If, an FX Audio, what happened to the original tubes?
The 6AU6's draw nearly twice the current of a 6AK5, 300ma's versus 175 and I don't know what effect that will have.
I honestly think, if a 6AU6 improved the sound over a 6AK5 the market would have discovered it by now.
The international prices of the two different tubes tells me that hasn't happened.
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Yes china does deliver here but most of time it isn't reliable and got lost in the process.
From china it will cost me about $60-74 total to get it here most of the cost comes from the tax.
Fx-Audio 03 and a DIY kit
The tubes is still here curious about rolling another type of tube.
also in the local antique shop a pair NOS tubes only cost me about $10-20 in local currency ranging from GE,Raytheon,NEC, to Philips. So little reason to get it for $60 imported.
 
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