[Andykong]

HA300 sounds fantastic for both my ZMF VC and Susvara with the Susvara always dead silent while the VC is more susceptible to picking up noise e.g RF, ringing of 300B tube as it warms up etc, depending on the tubes used, in my system. I even heard some Indian music playing very faintly (probably my neighbour) but when I lifted the ZMF cable it disappears (I suspect either RF or something coming through our shared powerline as I live in a complex). I have rolled many tubes so far and only one pair was dead silent for the VC whereas the Susvara is dead silent for everything
My chain is Gaming PC->Qobuz->Pontus II or Hugo 2->HA300B. So far I am really enjoying the Hugo 2 with the Susvara for the extra bass on the Hugo 2 extra bass filter while sacrificing a little of the 3D holographic nature of the Pontus II
Example track for Susvara god-like performance, Tchaikovsky: 1812 Overture, Op. 49, TH 49, the tiny sound of the triangle dinging away in the blackness in its own airy space blew my mind when I first heard it on the Sus
https://open.qobuz.com/track/161042622

Maybe when you lift the cable, your body has grounded the headphone cable and silent the RF interference.

Not sure if improving the shielding of your headphone cable can solve the problem, but it is worth trying if you have a pair of headphone cables with strong shielding. What I have in mind is something similar to Gotham 11281 or 11288, these GAC-4/1 cables are double-shielded, star-quad cables with LCOF Copper. The 11301 is their "extremely affordable" flagship balanced audio cable with a similar design but is too thick for headphones applications.

 

[Wes S]

Haha, I would hear RF-related music on the HA-300 while using the VC as well. The positioning of the cable and time of day affected how strong the radio signal would come in (Country music in my case; is this what they call a "value added"?). In the worst case, I could actually make out the words in the vocals. Funny enough though, after moving about 300 feet away in the same building, this added functionality has been removed.

Among my headphones, the VC is the most sensitive to RF noise and especially tube noise. The Utopia (which is of course very sensitive but lower Z) picks up quite a lot less so.

And of course as you say, the Susvara is dead quiet, because... Susvara. Same has been true for every planar I've ever used with the HA-300 (maybe about 6 in total).

I started getting some noise/interference with my VC's, and it was actually from the router in a completely different room. My roommate had moved the router and put it on the ground in the room next to me, and out of nowhere I started getting noise. Without knowing the router had been moved, I tried everything to get rid of the noise, for instance moving the amp to another outlet, changing tubes and cables, adding several different power conditioners, etc. . .and nothing helped. Then I realized the router had been moved and that was the only thing that had changed once the noise started happening. So, on a whim I moved the router back to a higher location on a book shelf in that same room next to mine, and the noise is completely gone. The VC's let you hear everything, and once all noise issues are addressed and the amp is quiet, that everything becomes micro detail and little nuances that come through instead of unwanted noise and it's blissful listening. I thought this was worth sharing, as I never would have thought a router in another room could cause noise/interference being so far away.

 

[skylinekursk]

decided jump in with ha300 mk2 as tube amp in my set up.
Heddphone, lcd5 and Susvara are some heavyweights for 300b...we will see how it goes..

 

[ThanatosVI]

decided jump in with ha300 mk2 as tube amp in my set up.
Heddphone, lcd5 and Susvara are some heavyweights for 300b...we will see how it goes..

Keep us updated

 

[ColSaulTigh]

decided jump in with ha300 mk2 as tube amp in my set up.
Heddphone, lcd5 and Susvara are some heavyweights for 300b...we will see how it goes..

Psst....hey buddy? Yeah, you. Can I interest you in some Elrogs???

[Opens trenchcoat]

 

[jamato8]

Perv alert. lol

 

[EagleKent]

Maybe when you lift the cable, your body has grounded the headphone cable and silent the RF interference.

Not sure if improving the shielding of your headphone cable can solve the problem, but it is worth trying if you have a pair of headphone cables with strong shielding. What I have in mind is something similar to Gotham 11281 or 11288, these GAC-4/1 cables are double-shielded, star-quad cables with LCOF Copper. The 11301 is their "extremely affordable" flagship balanced audio cable with a similar design but is too thick for headphones applications.

Thanks Andy. That's good info. Happy to report I have kept my ZMF cable lifted and the RF interference hasn't come back so far. I will explore the cable options if the RF comes back

 

[Andykong]

Thanks Andy. That's good info. Happy to report I have kept my ZMF cable lifted and the RF interference hasn't come back so far. I will explore the cable options if the RF comes back

Its a pity that most headphone cable didn't take anti-RF interference into consideration. a pair of unshielded 2m to 3m cable can easily act like an RF antenna, especially when you are using a full-tube headphone amplifier which normally operated in high impedance.

 

[Andykong]

On the last day of 2022, we want to thank our friends and users for your long-term support and participation. Your contribution is the main reason that endorses HA-300MK2 as one of the benchmarks for the Personal Audio community. Headfonics has named HA-300MK2 as the Best Tube Amplifier in 2022, and we believe HA-300MK2 is also the best vacuum tube headphone amplifier to a lot of personal encaustic in this thread.

2022 is a difficult year, we are looking forward to 2023 and with your support, we'll bring more joy and fun to all cayin friends and users in the coming year.

 

[jamato8]

On the last day of 2022, we want to thank our friends and users for your long-term support and participation. Your contribution is the main reason that endorses HA-300MK2 as one of the benchmarks for the Personal Audio community. Headfonics has named HA-300MK2 as the Best Tube Amplifier in 2022, and we believe HA-300MK2 is also the best vacuum tube headphone amplifier to a lot of personal encaustic in this thread.

2022 is a difficult year, we are looking forward to 2023 and with your support, we'll bring more joy and fun to all cayin friends and users in the coming year.

Yes, it is an extremely good amp at a reasonable price.

 

[Erwinatm]

On the last day of 2022, we want to thank our friends and users for your long-term support and participation. Your contribution is the main reason that endorses HA-300MK2 as one of the benchmarks for the Personal Audio community. Headfonics has named HA-300MK2 as the Best Tube Amplifier in 2022, and we believe HA-300MK2 is also the best vacuum tube headphone amplifier to a lot of personal encaustic in this thread.

2022 is a difficult year, we are looking forward to 2023 and with your support, we'll bring more joy and fun to all cayin friends and users in the coming year.

Can't agree more Andy...keep up the good work Cayin...

Happy New Year 2023 every one

 

[Wes S]

On the last day of 2022, we want to thank our friends and users for your long-term support and participation. Your contribution is the main reason that endorses HA-300MK2 as one of the benchmarks for the Personal Audio community. Headfonics has named HA-300MK2 as the Best Tube Amplifier in 2022, and we believe HA-300MK2 is also the best vacuum tube headphone amplifier to a lot of personal encaustic in this thread.

2022 is a difficult year, we are looking forward to 2023 and with your support, we'll bring more joy and fun to all cayin friends and users in the coming year.

I am happy to own such an amazing amp, and it continues to blow my mind both sonically and visually every time I use it. Cayin has truly created a masterpiece!

Congrats to Cayin on a well deserved award and thanks for the continued support Andy!

Happy New Year and Happy Listening to all.

 

[msq123]

I have a very bizarre situation with T1.6AL250V fuse next to power supply blowing up with certain combination of tubes.

I recently acquired KenRad JAN VT231 clear glass and it was working fine when I had it paired with Elrog 300 and Sylvania or GE 22De4. This morning to test out I swapped Elrogs and rectifier tubes to stock and as soon I started the amp fuse blew up, went through 4 fuse and then I swapped VT231 with stock TungSol GT231B and it worked fine. And then I swapped back VT231 but changed power to Elrog and rectifier to Sylvania and that combination worked too without issues.

So for some strange reason this amp doesn’t like combination of KenRad with stock power and rectifier. My understanding is VT231 and GSN7GTB are the same tubes just different inventory numbers and there shouldn’t be any difference in the spec? Is that correct?

If the Kenrad VT231 was faulty it wouldn’t run with Elrog but no issues there so is it that the combination with stock is too hot or is it the combination with stock RCA 22DE4. I will try that out too so I can get to the actual combination causing the issue but I am clueless as why this could be happening in the first place.

Anyone got any insight on this or faced similar situation where certain pairing of tubes doesn’t work?

PS - I have had issues with blown fuse in the past but that was sorted when I ensured pre amp volume pot was down to min when starting but there has been no blown fuse since I switched to Elrog so GoldLion 300b could have issues and I am picking up wrong end of the stick with KenRads?

 

[ColSaulTigh]

I have a very bizarre situation with T1.6AL250V fuse next to power supply blowing up with certain combination of tubes.

I recently acquired KenRad JAN VT231 clear glass and it was working fine when I had it paired with Elrog 300 and Sylvania or GE 22De4. This morning to test out I swapped Elrogs and rectifier tubes to stock and as soon I started the amp fuse blew up, went through 4 fuse and then I swapped VT231 with stock TungSol GT231B and it worked fine. And then I swapped back VT231 but changed power to Elrog and rectifier to Sylvania and that combination worked too without issues.

So for some strange reason this amp doesn’t like combination of KenRad with stock power and rectifier. My understanding is VT231 and GSN7GTB are the same tubes just different inventory numbers and there shouldn’t be any difference in the spec? Is that correct?

If the Kenrad VT231 was faulty it wouldn’t run with Elrog but no issues there so is it that the combination with stock is too hot or is it the combination with stock RCA 22DE4. I will try that out too so I can get to the actual combination causing the issue but I am clueless as why this could be happening in the first place.

Anyone got any insight on this or faced similar situation where certain pairing of tubes doesn’t work?

PS - I have had issues with blown fuse in the past but that was sorted when I ensured pre amp volume pot was down to min when starting but there has been no blown fuse since I switched to Elrog so GoldLion 300b could have issues and I am picking up wrong end of the stick with KenRads?

I've not encountered any issues with my VT231's (Tung Sol, Sylvania, RCA) and any of my 300B tubes (granted, I don't have the same stock pair you do, and I'm running a different amp. But to answer your question, no, the VT231's should all be the same unless you got a weird variant.

 

[msq123]

I've not encountered any issues with my VT231's (Tung Sol, Sylvania, RCA) and any of my 300B tubes (granted, I don't have the same stock pair you do, and I'm running a different amp. But to answer your question, no, the VT231's should all be the same unless you got a weird variant.

I have narrowed it down to GoldLion 300b stock tubes. Tried every other possible combination and have no issues and even in the past every time there was a blown fuse these tubes were in the mix. They do work fine mostly but maybe with certain combinations there is a surge at start up which trips the fuse. I don’t have a tube tester yet so can‘t be absolutely sure but I am going to be more careful when working with these tubes, definitely not with KenRad input tubes .