[jambaj0e]

I know 2400mW means 2.4W. I meant, why is single-ended written as 2400mW +2400mW? Why the addition symbol and the two numbers?

 

[LCMusicLover]

I know 2400mW means 2.4W. I meant, why is single-ended written as 2400mW +2400mW? Why the addition symbol and the two numbers?

They used to say ‘...xxx watts per channel...’ Same idea. It’s all just marketing copy.

 

[jambaj0e]

Dies anyone have better, high resolution photos of the inside of both units?

 

[Stefanbat]

I had a problem while auditioning the HA-300 on original tubes, that it to warm for my taste.
Does tube swaping for some 500$ 300B, can make this amp sound colder?

 

[Andykong]

CRAP CRAP CRAP!! I just came home, and when I tried playing music, my Cayin HA-300 did not play any music! Nothing is going through it via RCA interconnect, and my right 300b tube is out.

I switched the two 300bs tube and the one that didn't light up stayed off.

I switched out both 300b tube with another set of 300b tubes, and while they light up, I'm still not getting any sound or even any VU meter.

To rule out any other components, I took out my old Drop THX AAA 789, and music played normally on them.

This is INCREDIBLY frustrating!! This amp is only from November and I am getting NOTHING now!

Sigh, well, I managed to convince the guy I bought it for a refund and I returned it.

I think I'll buy the Ha-300 straight from the Musictek dealer, unless you guys can suggest much better 300b Amp in the same price range.

The question is, am I going to have to worry about the long term reliability of the Ha-300? This was stressful as hell.

Sorry to know that you have run into some problem with your HA-300. We resume operation today after a long break but I still can't get hold of the Engineer and get his advice on your case. Only one out of three support engineers are available today.

If the tubes are lighting up and the transformer were running warm, then the problem is likely a minor one, but troubleshooting might be a bit inconvenient. Anyway this is nothing much we can do right now. I assume the original owner will contact his dealer and the case will come back to us through other channel.

MusicTeck is a good dealer with reputable track record in customer service, he takes good care of his customers. I sincerely hope you'll have an satisfactory experience if you decided to go for HA-300 again.

 

[Andykong]

I had a problem while auditioning the HA-300 on original tubes, that it to warm for my taste.
Does tube swaping for some 500$ 300B, can make this amp sound colder?

Tube rolling definitely will change the sound signature, especially if you prefer a more transparent and neutral (less-warm) presentation, but I think you should start with roling the 6SN7 instead of the 300B tubes. I believe options such as Sylvania vt231 and Sylvania 6SN7W might fit your bill. I am not a tube guy so I am sure there are better 6SN7 options out there.

 

[Andykong]

Dies anyone have better, high resolution photos of the inside of both units?

I only have the internal photo of the Amp box.

 

[Andykong]

You know, one thing I don't quite understand is how to read Cayin's headphone power ratings. Why is it written as a "mW number + mW number" for both Balanced and Single-Ended. For example Balanced has 2200mW+2200mW for medium impedance and 3700mW+3700mW for high.

Single-ended, surprisingly, is showing more power, correct? How do you interpret 2400mW+2400mW (M) and 5000mW+5000mW (H)?I did notice that single ended is louder, but I always thought balanced would be more powerful than single-ended.

You can read that as 2.2Wpc for medium impedance, that will be the common presentation of speaker amplifier. The specification of headphone amplifier appears in different format. Some manufacturer provides one numbers without stating whether that is total output or per channel output, so we want to stated explicitly that this is per channel rating.

The output power of transformer coupled tube amplifier is NOT a linear function like Solid State amplifier, and balanced is NOT necessarily more powerful then single-ended. The design (winding) of the transformer plays a deciding role here, not the amount of electrical components, especially when the 300B and 6SN7 are operated in Single-ended configuration.

 

[Andykong]

Have any current or former owners compared XLR vs RCA inputs? If I'm to interpret @Andykong's post from a while back correctly, it sounds like RCA ought to be the optimal input, all other things being equal.

I started comparing the XLR and RCA inputs this evening and was surprised to discover that I highly preferred XLR, but I'm guessing my findings are more about the quality of my respective interconnect cables rather than that of the amp's inputs. My XLR interconnects are Danacable Diamond Reference 1-meter, and my RCA interconnects are Danacable Diamond mk1 (non-Reference) 0.5-meter. The result using XLR was considerably punchier, deeper bass (always a welcome thing with a tube amp) and more extended treble and air, and generally slightly better all the way around. This was with the Abyss Phi TC.

Both connections were active simultaneously, going from the DAC to the HA300. It was easy and quick to volume-match by adjusting digital volume on the DAVE by +/- 6dB. Worth noting too is that the DAVE's preferred output is supposed to be RCA (though I doubt the DAVE's XLR loses much if at all to RCA in practice).

Anyway, if I could be half-way confident that the better results I'm getting via XLR is due to the interconnects and not the amp input, I may have to spring for another set of Diamond Ref's but with RCA terminations this time (since my current XLR pair are normally in use with my solid state amp), so was curious to know if anyone had anything thoughts...

I took part in those earlier posts by Andy and shared the signal path diagrams. The point was never that the RCA signal path would be better in any way, it was just that it was more direct beause a 300B tube is single-ended (it could be balanced, but that's not the point here wit hthe HA-300) and thus the middle of this amp is single ended. So going RCA in->6.3mm out is the least complicated and most direct path through this amp.

However, Cayin winds there own transformers and the XLR/balanced input transformer->SE signal->300B tubes->XLR/balanced output transformer was DESIGNED into the amp from the drawing board. It's not an afterthought and not half-assed implementation. And by leveraging the balanced input transformer and balanced output transformer, the designers would have even more control in delivering a target sound signature rather than being more exposed with the RCA input (source quality/choice) and RCA output (tube quality/choice).

So, your finding about the cables might just mean that you're finding the XLR input and XLR output of the amp are better than the RCA and 6.3mm ones. It could also be your cables, that's true, but when you've got ones that are already both "good", it doesn't add up to me that the clear preference you've found must be coming from the marginal differences in cables rather than the significant differences in amp signal path.

Do you have any other ideas what might be going on? It's an interesting topic, and those are nice interconnects and headphones you've got on either end of that amp

The RCA route is not better, but its is a slightly simpler route. The XLR input will convert to singled-ended by a pair of input transformer before feeding to 6SN7, everything is identical after that. Since converting from Balanced to Single-ended is relatively straightforward, I doubt you can hear the different, after volume matched, because of the extra conversion stage, maybe when you are using a very revealing system and you are purposively looking for the different.

 

[Andykong]

By the way, what line level voltage are you guys outputting from your DAC to the HA300? I'm still trying to decide whether to use 3V or 2V from my Qutest.

I recommend you use 2V from the Qutest, that 's the input level we used during R&D and final fine turning.

 

[Jarle]

I had a problem while auditioning the HA-300 on original tubes, that it to warm for my taste.
Does tube swaping for some 500$ 300B, can make this amp sound colder?

Psvane WE Series WE300B. Compared to Full Music they are colder (more neutral), significant more transparent, dynamic and joyful with an articulated bass.

 

[jambaj0e]

Sorry to know that you have run into some problem with your HA-300. We resume operation today after a long break but I still can't get hold of the Engineer and get his advice on your case. Only one out of three support engineers are available today.

If the tubes are lighting up and the transformer were running warm, then the problem is likely a minor one, but troubleshooting might be a bit inconvenient. Anyway this is nothing much we can do right now. I assume the original owner will contact his dealer and the case will come back to us through other channel.

MusicTeck is a good dealer with reputable track record in customer service, he takes good care of his customers. I sincerely hope you'll have an satisfactory experience if you decided to go for HA-300 again.

I ended buying an ha-300 straight from Musictek this time & it should come this week! Hope to have a better experience since I really like the Amp!

 

[jambaj0e]

Psvane WE Series WE300B. Compared to Full Music they are colder (more neutral), significant more transparent, dynamic and joyful with an articulated bass.

You'd choose the Psvane WE 300B over the ACME? If I want something like the WE, but warmer, what's my best choice?

 

[JinTam]

I ended buying an ha-300 straight from Musictek this time & it should come this week! Hope to have a better experience since I really like the Amp!

I just had a similar event with the amp almost going dead. It turns out that the sockets were loose and the service center tighten them up and it works flawlessly again. Seems to be the 300B and 6SN7 sockets.
Other symptoms were one of the channels would go silent.

Anyways, I hope this helps some body with similar problems.

 

[jambaj0e]

Question: Do you tend to leave your HA-300 when you're not using it? Here's an interesting video regarding if it's better to leave electronic equipment on or not:

Does leaving equipment on shorten its life?