[DMITRIY R]

Does the amp need to be adjusted when changing tubes? Or this is a "plug and play" device, put in the same tube from another manufacturer and listen?

 

[Wes S]

Does the amp need to be adjusted when changing tubes? Or this is a "plug and play" device, put in the same tube from another manufacturer and listen?

It's plug and play. You want the power and driver tubes to be matched (for channel balance), and the rectifiers don't have to be matched. Cayin mentions all this in the manual by the way, of which can be downloaded for free if you don't have one or want one.

This amp definitely becomes an absolute beast with the right tube combo.

 

[Andykong]

I have a question about the measurements of plate currect and transconductance.

I purchased a matched pair of Sophia Electric Princess Mesh Plate 300B tubes, and this is their specification as listed on their website.

See - https://sophiaelectric.com/pages/pages-se-princess-300b-specification

Note that it states a plate current of 62.5 ma and a transconductance value of 5700 as their specification. However, the matched pair that I received has a plate current measurement of 54ma and a tranconductance measurement of 4,400. Does that difference imply that my received 300B tubes are deficient in some way?

Also, I have attached a copy of the measurements of a particular person's WE 300B tube.

Note that it states a plate current of 82.9ma and a transconductance measurement of 5,190.

I read somewhere that a person was using a 300B tube that caused his tube amplifier's fuse to continuously blow and the amplifier manufacturer stated that the 300B tube's plate current was too high for that amplifier.

Can that apply to the Cayin HA300BMK2 headphone amplifier? Can it handle a high plate current of 82.9ma?

Jeff.

I have consulted our Chief Engineer (Chen DeHai) and confirmed that our HA-300 and HA-300MK2 can work with the WE300B tube with a plate current of 82.9ma. So please go ahead and plug it in.

 

[Skyediver]

@Andykong , hope you're well. Quick question, and apologies if I missed it the thread: Can I use an 6SN7 adapter for ECC31, 6Z7, and 6Z7G tubes with this amp? I have a ton of these types of tubes from my Glenn OTL days that I'd like to repurpose as long as it's within the amp's tolerances, etc. Thanks!

 

[steve468]

Seems like this thread is dying down a bit, but for anyone looking for tube recommendations, I've really been digging Sylvania 6F8G 1940's leaf logo lately. Just a nice balanced sound, maybe a little warm but not as much as other American brands. Great 3d soundstage, super bass that straddles presence and detail, and great detail in the midrange. I know in some other 300b threads here they're highly touted - they really do seem to pair well with the 300b sound. I never thought too much about Sylvania tubes until trying several in the HA-300.

 

[jamato8]

These blow away any 6F8G (and I have many NOS), 6SN7 (Many NoS and some of the best) and other types. The 7193, just has it all. Extremely open sounding, dynamic and layered. Quite surprising at the difference. Each 7193 is one half of a 6SN7 and has a Grid cap and Plate cap, which must be part of the secret.

The speed the delivery is startling. Adapters from China that work very well.

Also, these 1942 Kenrad tubes are extremely quiet. Also, they match super close. All the 7193 I have checked are very close in plate current draw and mutual conductance. No problem matching them to quads.

 

[steve468]

These blow away any 6F8G (and I have many NOS), 6SN7 (Many NoS and some of the best) and other types. The 7193, just has it all. Extremely open sounding, dynamic and layered. Quite surprising at the difference. Each 7193 is one half of a 6SN7 and has a Grid cap and Plate cap, which must be part of the secret.

The speed the delivery is startling. Adapters from China that work very well.

Also, these 1942 Kenrad tubes are extremely quiet. Also, they match super close. All the 7193 I have checked are very close in plate current draw and mutual conductance. No problem matching them to quads.

Can I ask where you found a matched quad of these?! I had been keeping on eye on eBay but gave up.

 

[jamato8]

Can I ask where you found a matched quad of these?! I had been keeping on eye on eBay but gave up.

I match them myself. I don't rely on anyone to match tubes, I have 8 tubes testers. I mainly use my 2 539C Hickoks which are both calibrated and super close to each other. I test all tubes on one tester and have digital meters to get correct settings and then for the plate current. These 7193 are all the same date code in original military does, Kenrad tubes.

These tubes, and what I have read about 7193s in general that they are quiet and these so far, with sensitive headphones, have no perceptible noise.

 

[jambaj0e]

)Seems like this thread is dying down a bit, but for anyone looking for tube recommendations, I've really been digging Sylvania 6F8G 1940's leaf logo lately. Just a nice balanced sound, maybe a little warm but not as much as other American brands. Great 3d soundstage, super bass that straddles presence and detail, and great detail in the midrange. I know in some other 300b threads here they're highly touted - they really do seem to pair well with the 300b sound. I never thought too much about Sylvania tubes until trying several in the HA-300.

(Pardon the dust!)

Absolutely love the pairing of my Western Electric 300b and Sylvania 6SN7W metal tubes. Pricey, but such a great combination with soundstage, speed, texture, bass extension, and beautiful mids and vocals.

 

[ARCXENOS]

Much thanks to @Wes S for helping me identify which RFT I want, they definitely have an unique construction, It took months to get a pair (that isn't ebay levels of prices), but it was all worth it. I have been enjoying them since last week, it is a fantastic experience

I figured some of the MELZ 1578 guys might wanna know the difference between both, here are some summary notes of my opinions using them with the Elrog :

- If you have heard of the Kenrad VT231 and Telefunken ECC82 smooth plates, IMO these are the perfect cross between both, it has a nice blend of smoothness and impactful bass, but most importantly on the Elrog, the bass do not reach the muddy levels that the kenrads can get to sometimes.
- MELZ 1578 and the RFT have different sound profiles, I don't think they are really comparable directly. RFT sounds faster with harder hitting bass, whilst the MELZ is more towards the sparkly brighter side of things, it has a wider stage and more defined instrument separation
- I consider both RFT and MELZ to be well balanced in tonality, you will not go wrong with either for everyday general usage, but I found them different enough to warrant to get both. I do not think the MELZ lacks bass, the same way I do not think the RFT lacks treble presence - but long story short, go RFT if you want bass, go MELZ if you want treble
- I must stress that the RFT bass is really good, its a well controlled kenrad IMO!!
- Noise floor wise, maybe I have lucked out, but testing with my Focal Utopia, both the Melz and RFT are quiet - I think it is possible to get low noise units of both. But I am sure you can visit the 6SN7 thread for tips on soldering pins if necessary


I guess I am a fan of German tubes now, Elrog, Telefunken and RFT all have been a hit for me

 

[incredulousity]

Absolutely love the pairing of my Western Electric 300b and Sylvania 6SN7W metal tubes. Pricey, but such a great combination with soundstage, speed, texture, bass extension, and beautiful mids and vocals

These blow away any 6F8G (and I have many NOS), 6SN7 (Many NoS and some of the best) and other types. The 7193, just has it all. Extremely open sounding, dynamic and layered. Quite surprising at the difference. Each 7193 is one half of a 6SN7 and has a Grid cap and Plate cap, which must be part of the secret.

The speed the delivery is startling. Adapters from China that work very well.

Also, these 1942 Kenrad tubes are extremely quiet. Also, they match super close. All the 7193 I have checked are very close in plate current draw and mutual conductance. No problem matching them to quads.

Damn. Now look what you made me do!

 

[Andykong]

@Andykong , hope you're well. Quick question, and apologies if I missed it the thread: Can I use an 6SN7 adapter for ECC31, 6Z7, and 6Z7G tubes with this amp? I have a ton of these types of tubes from my Glenn OTL days that I'd like to repurpose as long as it's within the amp's tolerances, etc. Thanks!

We have listed several recommended replacement tubes in the user manual, these are the tubes we tested and confident that different implementation will work fine in HA-300MK2.

Offically we don't recommend expanding the replacement pool by adding adapters. We knows tube audiophiles have been doing these regularlly, but as a manufacturer, we cannot take the risk to recommend something that involves a lot of variables.

 

[Wes S]

Much thanks to @Wes S for helping me identify which RFT I want, they definitely have an unique construction, It took months to get a pair (that isn't ebay levels of prices), but it was all worth it. I have been enjoying them since last week, it is a fantastic experience

I figured some of the MELZ 1578 guys might wanna know the difference between both, here are some summary notes of my opinions using them with the Elrog :

- If you have heard of the Kenrad VT231 and Telefunken ECC82 smooth plates, IMO these are the perfect cross between both, it has a nice blend of smoothness and impactful bass, but most importantly on the Elrog, the bass do not reach the muddy levels that the kenrads can get to sometimes.
- MELZ 1578 and the RFT have different sound profiles, I don't think they are really comparable directly. RFT sounds faster with harder hitting bass, whilst the MELZ is more towards the sparkly brighter side of things, it has a wider stage and more defined instrument separation
- I consider both RFT and MELZ to be well balanced in tonality, you will not go wrong with either for everyday general usage, but I found them different enough to warrant to get both. I do not think the MELZ lacks bass, the same way I do not think the RFT lacks treble presence - but long story short, go RFT if you want bass, go MELZ if you want treble
- I must stress that the RFT bass is really good, its a well controlled kenrad IMO!!
- Noise floor wise, maybe I have lucked out, but testing with my Focal Utopia, both the Melz and RFT are quiet - I think it is possible to get low noise units of both. But I am sure you can visit the 6SN7 thread for tips on soldering pins if necessary


I guess I am a fan of German tubes now, Elrog, Telefunken and RFT all have been a hit for me

Good stuff! The German's sure did and still do know what they are doing. If you like tight and super impactful bass, with speed and detail, and a weighty sound that makes music sound alive, look no further. RFT and Elrog are where it's at for me.

Just out of curiosity, what year are your Melz? I have it on good authority, the 50's and 60's version sounds a bit different/better than the 70's-80's version.

 

[ARCXENOS]

Good stuff! The German's sure did and still do know what they are doing. If you like tight and super impactful bass, with speed and detail, and a weighty sound that makes music sound alive, look no further. RFT and Elrog are where it's at for me.

Just out of curiosity, what year are your Melz? I have it on good authority, the 50's and 60's version sounds a bit different/better than the 70's-80's version.

It has been awhile and my message with the seller seems to be cleaned up, my memory is failing me but I think it should be the 50's, according to my old notes

Maybe a melz-lord can appraise it

But 1 thing is for sure, bringing up the old legendary pic,

its the ledged mica one

 

[572217]

Hello head-fi experts,

I am building a new system for a new apartment. Sources are the Innuos ZEN Mk3 going into the dCS Bartók. Eyeing the Cayin HA-300MK2 to replace a HeadAmp GS-X mk2 to get more of the tube goodness. I use a Riviera AIC-10 to drive the DCA Stealth in another rig. That amp / headphone combo works beautifully.

Stealth is my preferred headphone. Personally enjoy it more than the Abyss 1266 Phi TC or the Susvara. Is anybody driving the Stealth with the Cayin? Does it deliver enough juice to make the Stealth sing - as it requires a lot of it? What is your listening experience with that combo?

Second question I own a ZMF Verité Closed but it gets little use. Love the experience with the Stealth too much. Would a ZMF Caldera be a lovely combination for the proposed chain? The Bartók is a capable source and provides deep insight into the music.