[vcoheda]

how is it that the amp died so soon after receiving it? that doesn't sound right.

 

[RockCity]

Riceboy forgot to poke air holes for the The Dragon?

 

[pompon]

I got my unit back ... from local repair.

Was

the bad part.

Old one was not attached firmy to the case for heat dissipation and got all the heat and finally burned.

 

[purk]

So how does it sound now?

 

[pompon]

I will test that shortly ...

I have done somes tests before he died but with a fault part, I will redo all my tests.

I have many tubes to test ... but probably 6SN7GT + 5687 seem to be the best or 2c51 or 6SN7GT + 6528a.

I have impressions the transformers are probably limit for 6528 tubes ... they are small. I can't drive my D5000 with them ... I have somes distortion in the bass section.

I will check that with a friend after Christmas ... once the amp is open, will be easy to check if transformers are strong enough ... if not, will think about mod it to replace them with bigger one.

 

[mikeymad]

Bad Rectifier?... I had that issue with my Cary... good to hear that it is back up and running.

Cheers,

 

[sacd lover]

Quote:

Originally Posted by pompon /img/forum/go_quote.gif I will test that shortly ... I have done somes tests before he died but with a fault part, I will redo all my tests. I have many tubes to test ... but probably 6SN7GT + 5687 seem to be the best or 2c51 or 6SN7GT + 6528a. I have impressions the transformers are probably limit for 6528 tubes ... they are small. I can't drive my D5000 with them ... I have somes distortion in the bass section. I will check that with a friend after Christmas ... once the amp is open, will be easy to check if transformers are strong enough ... if not, will think about mod it to replace them with bigger one.

The original owner of your amp brought the amp to my house for a meet. The amps transformer is plenty big enough for 6528s. One transformer is for the tube heaters and one is for the high voltage supply. That is why one transformer gets hotter than the other. The heater supply has a 20 amp transformer if I remember correctly, which again, is definitely enough to run 6528s. You should be able to drive any headphone with this amp.

Have you used the second driver stage yet? If the amp wont drive D5000s, which I highly doubt, try the second gain stage.

Try 6SN7 to 5687 to 6528 ....

 

[pompon]

I tried

6sn7gt + 5687
6sn7gt + 6bx7 + 5687
2c51 + 6528a
5687 + 6528a

All the same problem ... D5000 distord. My HD650 work fine.

I tend to think one of the transformer not working at 100% of it's capacity and with a certain charge, it's lack juice ...

Will check that with a friend with good knowledge with tube amp ...
With a meter, we will probably be able to see what going on.

It's not a matter of tubes because D5000 can be driven with my MPX3 (without any problem), LittleDot, internal soundcard (PC), portable amp, IPOD ...

By chance tube amp don't have a complicated circuit and all parts are available easily.

 

[pompon]

Quote:

Originally Posted by purk /img/forum/go_quote.gif So how does it sound now?

It's sound better ... before he was not playing at all. lol

In some words ...

- Dragon have more holographic 3D (more depth of soundstage and more height).
- Each instrument have more focus and apparent details. Width of soundstage is affected with a better focus and seem larger on the dragon.
- Each note is more articulated (dynamic). The average level seem lower on the dragon but peek have more room to raise.
- Little more bass extention on the dragon.
- Vocal are slighty more laidback on the Dragon ... probably an effect of the focus side effect.

* I am using the same powercord (stock 18 avg on Tripplite LC1800) and the same RCA X2 Oritek interconnect.
* I put both unit at the same level using pinknoise and SPL at 82dbc.
* Both unit perfectly warm up ...

On the Dragon I am using TungSol 2C51 + Centron 6528A and with the MPX3 the Sylvianna 6SN7GT + TungSol DGetter 5687 with herbies tube damper on 6sn7 and 5687.

It's my *preferred tubes on both unit. I have MANY mix I can do but all the others tubes I put on the Dragon was "different" or not better.

I think that Dragon will work good on my Sennheiser HD800.