Tube Rolling for Bellari HA540 - Page 2

Let me get this straight.  Earlier in the thread, you say:

Then when I post my impressions, you pout that I did what you asked?  I know there are no age limitations for posting but I sure wish there was a separate section for children.

I have no hidden agenda for "retaliation" against Bellari.  They did not send me a "lemon" and even if they had I wouldn't be unreasonable about it.  As I've said repeatedly it sounds "good" or "fine" in my system.  I said in my review that if I hadn't heard the Sunrise in my system, I'd be content with the Bellari.  I told you I'd let the sound quality determine which amp I personally think is best in my system and that's what I did.  You can dream up whatever imbecilic conspiracy theories you want.

And thanks for the insulting sarcasm!  Nice way to show your appreciation for me taking the time to compare them and report back as you had asked me to do.

I have tried Sylvania, Philips, Mullard 12AU7;  Westinghouse, Mullard 12AT7; Admiral, Sylvania, Mullard 12AX7; and a GE 5751 (all NOS) and found that the Westinghouse 12AT7 and GE 5751 were the best so far. The 12AX7 tubes are too high gain and sound way to piercing to my ears. This is with AKG Q701 and Denon AH-D2000 cans, both relatively low impedance headphones. Maybe with high impedance cans like Sennhiesers, the 12AX7 would be fine, but not with mine. Anyway, let's keep this thread on topic and get away from the defensive bickering. Enjoy.

Also wanted to state that the high and low inputs on the Bellari do not change the gain, they have to do with the sensitivity. With low power inputs like MP3 players, the low works better, but with steady power inputs like cd players, DAC, etc the high input works best. Or at least that's what I read in the info sheet with the amp.

It's been a few months since I last posted here, thought I'd update my Bellari HA540 experiences. I've been using a NOS Mazda 5751 tube almost exclusively since July - about 60 hours I guess. This has been absolutely magical with my main phones, the Grado PS500 and now the RS1i. The lower gain of the 5751 makes a big difference with the Grados which are low impedence. The tube amp that is most often recommended by Grado fans is the Mapletree ($700) which also uses a 5751, and I think that is a big reason why. That is not the tube I use with harder-to-drive cans such as my AKG Q701 - this is why I love the versatility of the Bellari and the 12ax7 tube. Other tubes I highly recommend are Sylvania 7025 and any of the RCA blackplates (including 5751 which is 1/2 the price of a Mazda). All things considered, I think the HA540 is a huge bargain for a quality tube amp - I am definitely enjoying mine! 

Quote:

Originally Posted by desertblues 

It's been a few months since I last posted here, thought I'd update my Bellari HA540 experiences. I've been using a NOS Mazda 5751 tube almost exclusively since July - about 60 hours I guess. This has been absolutely magical with my main phones, the Grado PS500 and now the RS1i. The lower gain of the 5751 makes a big difference with the Grados which are low impedence. The tube amp that is most often recommended by Grado fans is the Mapletree ($700) which also uses a 5751, and I think that is a big reason why. That is not the tube I use with harder-to-drive cans such as my AKG Q701 - this is why I love the versatility of the Bellari and the 12ax7 tube. Other tubes I highly recommend are Sylvania 7025 and any of the RCA blackplates (including 5751 which is 1/2 the price of a Mazda). All things considered, I think the HA540 is a huge bargain for a quality tube amp - I am definitely enjoying mine! 

I'm trying out the JJ Electronic gold pins on the Bellari HA540.  They just came in today and I'm slowly burning them in.  I appreciate the above posts and will be tube rolling the Sylvania 7025 next. 

Nice to see some other Bellari HA540 users. It is a nice amp. Just to share, I saw this review on Amazon 

http://www.amazon.com/review/R3P9VK1YU3KA08/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B004FI6AKW&linkCode=&nodeID=&tag=

The user recommends switching to another power supply as the HA540 is rated to run at 15v 700ma but the included wallwart is only 15v 200ma. They claim an increase in soundstage depth and and after changing to another power supply myself, I would agree.

Quote:

Originally Posted by DTKZ 

Nice to see some other Bellari HA540 users. It is a nice amp. Just to share, I saw this review on Amazon 

 

http://www.amazon.com/review/R3P9VK1YU3KA08/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B004FI6AKW&linkCode=&nodeID=&tag=

 

The user recommends switching to another power supply as the HA540 is rated to run at 15v 700ma but the included wallwart is only 15v 200ma. They claim an increase in soundstage depth and and after changing to another power supply myself, I would agree.

What power supply did you change to?

I just got one of those regulated switchable power supplies that can provide 15v 800ma  from a electrical store here. If you want to play it safe, you could get the Rolls PS15 mentioned in the review. I would have gone for that myself but it's not available here in Singapore. Looks like there are quite a few online US retailers that carry it, so it should be easy for you though.

Quote:

Originally Posted by DTKZ 

I just got one of those regulated switchable power supplies that can provide 15v 800ma  from a electrical store here. If you want to play it safe, you could get the Rolls PS15 mentioned in the review. I would have gone for that myself but it's not available here in Singapore. Looks like there are quite a few online US retailers that carry it, so it should be easy for you though.

Thanks for the advice I will try that out.

Yes, I read that on Amazon too and ordered a Rolls PS15 for about $20. I have noticed an improvement and think it's worth it.

I upgraded to the PS15 and will give the feedback when they come in.  I also ran down some vintage (1960) Telefunken 12AX7 to try out.

I'm curious. Do you guys feel that NOS really provide a much better sound? I have a bunch of tubes, but they're all current production. I could get some NOS ones but they're quite a bit more expensive. Also, have you tried any of the lower gain tubes such as 12AT7s or 12AU7? I don't have any high impedance cans and never go past the 12 O'clock mark on volume so I've been thinking that I don't really need the gain of 12AX7s.

I'm new to tubes, so I haven"t been able to compare more than two contemporary tubes.  Bellari on their FAQ area claimed that the best sounding tubes they heard were Telefunken so for about 2 & 1/2 x's normal tubes I decided to give them a try.

DTKZ, there is a marked difference between the NOS tubes and the new issue tubes I have tried. I have tried new and old 12ax, at, au7 tubes and the NOS tubes sound so much better to my ears. I have enjoyed my 12AU7 tubes the most, especially since I got the Audioengine D1 DAC because of the variable output on it. Without it, I wouldn't be able to get enough volume for my Q701. The D2000 work beautifully with them too. Less noise, less piercing treble. However, I have a 5751 and a 12AT7 that sound almost as good as the Mullard 12AU7 I use the most. NOS tubes are worth the money if you look for good local places to get them, places you can trust to sell you solid working tubes, not faulty b or c stock units.