[sonnysound]

There would be no issue buying new tubes as they triodes will be balanced. There is little risk in buying used tubes as long as they have been tested and verified to have balanced triodes and that they test strong. Good listening, SonnY

Matched tubes refer to power tubes being current matching for bias requirements. There is no such requirement to current match preamp driver tubes. Most headphone amps are self biasing. Cheers, SonnY PS: Testing preamp driver tubes, especially dual triodes, requires balanced or close test results on both sides of the triodes and between the tubes if there are more than one. Most of all these discussions are way more complicated than they need to be. Upgrading to vintage USA/European tubes will be easy and will increase performance and sound quality. Good listening, SonnY

 

[Slipmyster]

Matched tubes refer to power tubes being current matching for bias requirements. There is no such requirement to current match preamp driver tubes. Most headphone amps are self biasing. Cheers, SonnY PS: Testing preamp driver tubes, especially dual triodes, requires balanced or close test results on both sides of the triodes and between the tubes if there are more than one. Most of all these discussions are way more complicated than they need to be. Upgrading to vintage USA/European tubes will be easy and will increase performance and sound quality. Good listening, SonnY

Hi Thank you for all your help.
I've ordered a couple of Sylvania nos and the electro harmonix new tube's so with the jj's that are in it I should be good for a while.
I'll let you know how I get on.
Thanks again

Martin

 

[tomb]

Matched tubes refer to power tubes being current matching for bias requirements. There is no such requirement to current match preamp driver tubes. Most headphone amps are self biasing. Cheers, SonnY PS: Testing preamp driver tubes, especially dual triodes, requires balanced or close test results on both sides of the triodes and between the tubes if there are more than one. Most of all these discussions are way more complicated than they need to be. Upgrading to vintage USA/European tubes will be easy and will increase performance and sound quality. Good listening, SonnY

Yes, with power tubes on a push-pull amp, it can destroy the amp if the tube outputs are not matched. While it won't damage the amp, mis-matched tubes in the signal stage are also important. Self-biasing? Yeah, if the circuit includes it, the tubes wilf self-bias based on the tube's output. So, if there's a mis-match in tube output, the self-bias will also result in channel imbalance.

This is not complicated. A single dual-triode tube is no different than two single triode tubes. ANY reputable tube dealer will test and also match tubes or multiple triodes within a single tube (but not on ebay).

I agree with you that NOS tubes are better than new manufacture, but they must be tested and matched.

 

[DropTekRoon]

Does anyone know if the Spartan Helot 2x runs a 6.3v heater? I'm looking into a 6SN7 to 12AU7 adapter to use with the amp. The adapter says "your device must be configured to use center tap of an 12AU7 tube and work at 6.3v to work properly". The 6SN7 produces 600ma so I want to be sure that if I were to use one, it wouldn't fry anything. I would assume it would be fine though?

 

[Slipmyster]

Does anyone know if the Spartan Helot 2x runs a 6.3v heater? I'm looking into a 6SN7 to 12AU7 adapter to use with the amp. The adapter says "your device must be configured to use center tap of an 12AU7 tube and work at 6.3v to work properly". The 6SN7 produces 600ma so I want to be sure that if I were to use one, it wouldn't fry anything. I would assume it would be fine though?

Have you contacted Spartan music they are usually really good with advice. It would be great if you could let us know how you get on.

Martin

 

[DropTekRoon]

Have you contacted Spartan music they are usually really good with advice. It would be great if you could let us know how you get on.

Martin

Yes, the person that messaged me said that they are in the process of moving so it may take a week for them to get back to me. There's no information anywhere about the amp heaters. I'm assuming it would be fine to use a 6SN7 tube with the Helot 2x since I've tried that tube with another amp without any problems and that amp used a 5670 tube which outputs half the power of a 6SN7 tube. Just need to be sure it would be fine to do so.

 

[Slipmyster]

Yes, the person that messaged me said that they are in the process of moving so it may take a week for them to get back to me. There's no information anywhere about the amp heaters. I'm assuming it would be fine to use a 6SN7 tube with the Helot 2x since I've tried that tube with another amp without any problems and that amp used a 5670 tube which outputs half the power of a 6SN7 tube. Just need to be sure it would be fine to do so.

Ye I noticed there's very little information online. I also tried searching information on the Wang's pha t1 amplifier as it's the same amp with a different paint job but found nothing. Here's a picture of the t1

Martin

 

[DropTekRoon]

Ye I noticed there's very little information online. I also tried searching information on the Wang's pha t1 amplifier as it's the same amp with a different paint job but found nothing. Here's a picture of the t1


Martin

I've seen that amp before. I guess it's just a rebranded version of the Helot 2x. Only difference being that it's sold in the US compared to only Europe.

I was looking at some of the previous messages here. Did you ever try those Sylvania NOS tubes? Was there any noticeable difference compared to whatever tubes you were originally using?

 

[Slipmyster]

I've seen that amp before. I guess it's just a rebranded version of the Helot 2x. Only difference being that it's sold in the US compared to only Europe.

I was looking at some of the previous messages here. Did you ever try those Sylvania NOS tubes? Was there any noticeable difference compared to whatever tubes you were originally usingi

I am using the Sylvania tubes. The amplifier originally came with the JJs and they are very good but I do prefer the Sylvania's. The JJs are more punchy in the bass and they have more treble but the Sylvania have a lovely midband that the JJs just can't match. I also have the Eloctro Harmonix but I haven't tried them as of yet.

 

[DropTekRoon]

I am using the Sylvania tubes. The amplifier originally came with the JJs and they are very good but I do prefer the Sylvania's. The JJs are more punchy in the bass and they have more treble but the Sylvania have a lovely midband that the JJs just can't match. I also have the Eloctro Harmonix but I haven't tried them as of yet.

I am actually getting the amp this week. I wanted to try something else besides the hybrid amp I was using. It seemed like a good option considering the price and it had good reviews. Mine is coming with the Electro Harmonix and some other vintage tubes I got. I've never tried an OTL tube amp before so it'll be something new coming from using a ss and a hybrid amp. When I changed tubes on the hybrid amp, it was kinda hard to tell the difference from each one of them tbh. Makes sense though because it has a ss output and you aren't getting all of the tube sound compared to if you were to use an OTL amp. I'm hoping that it will be safe to use the 6SN7 tube on this amp.

 

[Slipmyster]

I am actually getting the amp this week. I wanted to try something else besides the hybrid amp I was using. It seemed like a good option considering the price and it had good reviews. Mine is coming with the Electro Harmonix and some other vintage tubes I got. I've never tried an OTL tube amp before so it'll be something new coming from using a ss and a hybrid amp. When I changed tubes on the hybrid amp, it was kinda hard to tell the difference from each one of them tbh. Makes sense though because it has a ss output and you aren't getting all of the tube sound compared to if you were to use an OTL amp. I'm hoping that it will be safe to use the 6SN7 tube on this amp.

You will have to let me know how you get in with it. I would be interested to know about the 6sn7 switch. I'm just using mine on a cd player with a pair of Philips shp9500 headphones and it has really opened my eyes to what can be achieved sound wise without breaking the bank.

 

[DropTekRoon]

You will have to let me know how you get in with it. I would be interested to know about the 6sn7 switch. I'm just using mine on a cd player with a pair of Philips shp9500 headphones and it has really opened my eyes to what can be achieved sound wise without breaking the bank.

I'll definitely keep you updated on when I get an answer. It is kinda dumb though how the director doesn't know the answer right away and said that they have to look more into it if you can use a 6SN7 tube or not.

 

[DropTekRoon]

Here is what the person sent me.. "I'm afraid my knowledge of electronics is quite basic and when designing this amp, I put forward a lot of criteria I wanted, as well as feedback on the prototype. But the actual design was done by a factory in China who made guitar amps I really liked. I'll ask them, but recently they've started to reply very slowly. I do think it should be ok though, the 12bh7 is more related to the transformer, so that's not a problem".

They sent me a picture of this asking if it helps. I don't really understand it though. All I wanted to know is if it would be safe to use a 6SN7 tube or not. I didn't think it would be this difficult to find out the answer. I ordered the adapter since they said it "should be ok".

 

[Slipmyster]

Here is what the person sent me.. "I'm afraid my knowledge of electronics is quite basic and when designing this amp, I put forward a lot of criteria I wanted, as well as feedback on the prototype. But the actual design was done by a factory in China who made guitar amps I really liked. I'll ask them, but recently they've started to reply very slowly. I do think it should be ok though, the 12bh7 is more related to the transformer, so that's not a problem".

They sent me a picture of this asking if it helps. I don't really understand it though. All I wanted to know is if it would be safe to use a 6SN7 tube or not. I didn't think it would be this difficult to find out the answer. I ordered the adapter since they said it "should be ok".

Hopefully someone with knowledge of diagrams will see your post. It sounds as though if it will fit they think it will work ok but I have no clue from that. This is also my first tube amp and I know very little as you have probably gathered from my earlier post's so I am learning something new here. I'm looking forward to finding out how you go on.

Martin

 

[DropTekRoon]

Hopefully someone with knowledge of diagrams will see your post. It sounds as though if it will fit they think it will work ok but I have no clue from that. This is also my first tube amp and I know very little as you have probably gathered from my earlier post's so I am learning something new here. I'm looking forward to finding out how you go on.

Martin

The problem isn't the tube fitting or not. As long as you have the correct adapter, it will fit. It has to do with the amp heater needing to run at 6.3v to work properly and not 12.6v. I ordered the adapter to try it out. I'll let you know if the amp blows up in a few days