[Wes S]

After comparing HA-6A and HA300 II extensively for several times, I agree with this opinion. Also the fact that to "unleash" the real capability of HA-300 II, we need high end 300B tube. I always think the differences between these two tube amps are like choosing which guitar is I like more. There are no absolute win/lose, just which one suit my mood or paired better with the rest of the system (headphone and DAC).

Out of curiosity, anyone ever compared HA300 II with Cayin CS-805A? https://en.cayin.cn/features/8/159/492.html (cc: @Andykong ). A speaker amp, with 300B tube, Class A, 50W of power, and also has headphone out.

When extensively comparing the two amps, what tubes were you using? Have you heard the HA300MK2 with Elrog or WE 300B's?

 

[TheMiddleSky]

When extensively comparing the two amps, what tubes were you using? Have you heard the HA300MK2 with Elrog or WE 300B's?

Sadly it's hard to get both 300B tubes you mentioned here, so no, never tried them. I tried several 300Bs (all of them under $1000), and what I like the most so far from KR Audio.

KR300B already show the improvement in sound that easily to be heard when compared to stock Gold Lion.

 

[jamato8]

For fun I changed out the caps for the input/driver tubes. I want to cover the teflon/silver wire with a black cotton as well. The ceramic caps are most likely a little better but these are more to my liking.

6C8C USSR Svetlana 1952 grey plate. Elrog 300B (not really a 300B tube but they work the same).

 

[Wes S]

For fun I changed out the caps for the input/driver tubes. I want to cover the teflon/silver wire with a black cotton as well. The ceramic caps are most likely a little better but these are more to my liking.

6C8C USSR Svetlana 1952 grey plate. Elrog 300B (not really a 300B tube but they work the same).

Nice! Where did you source those black caps from?

 

[jamato8]

Nice! Where did you source those black caps from?

They are available on eBay and sent from China. They are the best price from the seller linked. The shipping can be off so you have to ask them to adjust the shipping.

https://www.ebay.com/itm/283117187210

I also wish someone made a nicely finished adapter that looked complete without the plexiglass. The CV6/6C8C/7193 are that all will be used for me. No 6SN7 can match them. I have some NOS National Union black plate 7193 coming in. I am curious how they sound.

 

[jamato8]

I have replaced the slow blow for the 300B tubes (.1mA/100mA) with Littlefuse slow blow. I measured the resistance of the Littlefuse .1mA and it comes in at a consistent 5.7 ohms. Other brands I have checked range from 6 to 9 ohms in the same brand and the fuses I took out measured 6.2 ohms and 8 ohms. But what is also very important is the material used in the element of the slow blow and the end caps.

What I notice is a much larger sound stage, very dynamic and even more detail. Since the fuses play an important role in letting the current flow, those electrons seem to be happy with the Littlefuse, more so than other fuses. A very inexpensive upgrade! More like listening to speakers or a live feed with a lot of music.

 

[jonchard]

I have replaced the slow blow for the 300B tubes (.1mA/100mA) with Littlefuse slow blow. I measured the resistance of the Littlefuse .1mA and it comes in at a consistent 5.7 ohms. Other brands I have checked range from 6 to 9 ohms in the same brand and the fuses I took out measured 6.2 ohms and 8 ohms. But what is also very important is the material used in the element of the slow blow and the end caps.

What I notice is a much larger sound stage, very dynamic and even more detail. Since the fuses play an important role in letting the current flow, those electrons seem to be happy with the Littlefuse, more so than other fuses. A very inexpensive upgrade! More like listening to speakers or a live feed with a lot of music.

Do you mind sharing parts numbers for those fuses?

 

[jonchard]

Do you mind sharing parts numbers for those fuses?

Im struggling to find something that beats the Tung Sol VT-231 oval mica. Its exceptional. My perfection. The closest CV6 i have to date is the GEC's i had from Wes. They are closest but a touch brighter. The TungSol VT-231 doesnt put a foot wrong for me and its sounds utterly dynamic - To the point i might sell the other 4 sets of 6sn7 / CV6's i have to go all out for another set of VT-231's. Im using Susvara so might not be applicable to other 'phones.

 

[hung031086]

I'm looking for something like this for my tubes. I want all of them are the same look and and height. Anyone know where to get them ? I don't do tubes rolling. I just want rise them up because the front plate is too big.

 

[ARCXENOS]

I'm looking for something like this for my tubes. I want all of them are the same look and and height. Anyone know where to get them ? I don't do tubes rolling. I just want rise them up because the front plate is too big.

I have been using @Deyan 's socket savers since month 1, and its still really tight - I do alot of tube rolling. They look the exact same to me.

BTW 1 issue I have with those savers in the picture is that they are too tight, but apparently that is by design, I was supposed to use a screw driver to loosen them

 

[raindownthunda]

I'm looking for something like this for my tubes. I want all of them are the same look and and height. Anyone know where to get them ? I don't do tubes rolling. I just want rise them up because the front plate is too big.

These are the socket savers I use. No complaints: https://www.partsconnexion.com/SOCKET-74489.html

 

[SAMCL]

Does it fit for utopia? Any tube switching?

 

[hung031086]

I have been using @Deyan 's socket savers since month 1, and its still really tight - I do alot of tube rolling. They look the exact same to me.

BTW 1 issue I have with those savers in the picture is that they are too tight, but apparently that is by design, I was supposed to use a screw driver to loosen them

Does he have the tubes saver for 300b tubes ?

These are the socket savers I use. No complaints: https://www.partsconnexion.com/SOCKET-74489.html

I don't see they have the 300b ones.

 

[ARCXENOS]

Does he have the tubes save for 300b tubes ?

I don't see they have the 300b ones.

Ah, if you mean for the 300b, you would have to ask him - I have seen 300b savers out in the wild before, but I never felt the need to get them for the HA300bmk2, the recessed socket makes it very hard to hold the base to extract the 300b anyways.

https://www.ebay.com/itm/201198710749

I bought alot of stuff from mrs X before, but I have never bought these savers...I think her other stuff is good so it might be worth checking out, unless there is something I am missing.

Does it fit for utopia? Any tube switching?

If you meant how is the amp with the Focal Utopia, I love it

 

[SAMCL]

If you meant how is the amp with the Focal Utopia, I love it

Yep, i want know the sound paring with focal utopia, cause for me, too much on mid.