Bravo Audio - funny looking little tube amps - Page 115

Quote:

Originally Posted by johnnyb3 

Thanks, geetarman, for a thoughtful response. I sorta had upgraditis anyway, so I guess I'll pass that one along to a friend with higher-impedance cans. 

you're welcome & wise move on that ...

if your budget is tight, perhaps one of the fiio models will do the trick for you.  otherwise, i stand by my recommendation for project sunrise if you're looking for a tube hybrid or the O2 if you want to stick with solid-state.

Bought today a RCA Cable instead the 3.5 to 3.5mm i was using and when i was playing i noticed that the sound was all messed up, like the sounds that suposed to come from the left i was listening them on the right side of the headphones. I removed the audio enhancers programs i was using thinking it was from there, well it wasnt. Restarted the pc, no luck. Then I thought it could be the cable so i swapped them, white on red input and red to white input. And it worked!

So now im thinking is it the cable or the bravo that have the rca inputs swapped?

And is there a problem if i use them swapped even if thats the only way they work correctly?

The cable was quite cheap. Evology is the brand.

Oh, awesome! I've wanted a cheap tube amp for a while. I've been investigating this one by fred_fred: http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=200807704603#ht_4069wt_1041

^Anyone know how that might compare to the Bravo V1/V2? 

V1 and V2 is pure Class A amp. This one is not.

Quote:

Originally Posted by fiesta 

V1 and V2 is pure Class A amp. This one is not.

Ahh, thanks.

Replaced IRF630's to IRL520PBF's (the best mosfets I could find in Estonia) on mine amp and now I couldn't be happier :) Even that small tuning changes sound. No more cut off treble and muddy bass. Now V2 sounds concrete like SS amp, but with warmth and liquidity of tube amp. But I noticed that both right channel mosfets are much hotter. I can hold my finger on them maximum one second, but on leht channel mosfets I can hold my finger for about three/four seconds. Could anybody know, what's the problem?

Quote:

Originally Posted by MiLKMAN 

Replaced IRF630's to IRL520PBF's (the best mosfets I could find in Estonia) on mine amp and now I couldn't be happier :) Even that small tuning changes sound. No more cut off treble and muddy bass. Now V2 sounds concrete like SS amp, but with warmth and liquidity of tube amp. But I noticed that both right channel mosfets are much hotter. I can hold my finger on them maximum one second, but on leht channel mosfets I can hold my finger for about three/four seconds. Could anybody know, what's the problem?

offhand, i would say that more current is flowing thru right channel.  the right channel should sound louder than the left (is this the case?). 

have you adjusted the trimpot to match bias voltage on both sides?  if you have and this behavior is still continuing, then i would suggest checking the tube for section mismatch & replace it with one that has balanced sections.

Do i really need to unplug the hp's before turning OFF the amp, as well as, first turn ON the amp then plug the hp's?

Quote:

Originally Posted by apsol 

Do I really need to unplug the hp's before turning OFF the amp, as well as, first turn ON the amp then plug the hp's?

Yea, better to plug or unplug before touching the power switch.

Some of the newer designed single tube amp. come with a built in power up delay, to protect the headphones.

Hmm, i see. It annoys me, always doing that.

So Im thinking of buying a fiio e10, not only because i dont need to have this care, of unplug and plug, but because i heard it have a good synergy with the DT 990 PRO's. But Im not sure if its better than the bravo with a vintage mullard tube that i bought.

What do you think?
 

Quote:

Originally Posted by apsol 

Hmm, i see. It annoys me, always doing that.

 

So Im thinking of buying a fiio e10, not only because i dont need to have this care, of unplug and plug, but because i heard it have a good synergy with the DT 990 PRO's. But Im not sure if its better than the bravo with a vintage mullard tube that i bought.

 

What do you think?
 

The tube might(?) make the DT990s sound better.

Quote:

Originally Posted by MiLKMAN 

Replaced IRF630's to IRL520PBF's (the best mosfets I could find in Estonia) on mine amp and now I couldn't be happier :) Even that small tuning changes sound. No more cut off treble and muddy bass. Now V2 sounds concrete like SS amp, but with warmth and liquidity of tube amp. But I noticed that both right channel mosfets are much hotter. I can hold my finger on them maximum one second, but on leht channel mosfets I can hold my finger for about three/four seconds. Could anybody know, what's the problem?

The IRL520's will do the job, being better then the F counterparts, but you had settled for a Fairchild IRL510 then man, would you be in for a surprise. It is normal the mosfet's are more hotter now, this is normal. If you want to reduce the heat a bit, replace the the large 25v 6800uf power capacitor to a 25v 10000of or 35v 6800uf capacitor, don't worry the supply of more volts will not kill the amp, but right now that 25v 6800uf cap is limiting the power input into the amp from the 24v wallwart being used, a bump in v for the cap or uf will give it some more headroom providing a more clearer sound.

Remove the two resistors next to the tube near the LM317 mosfets (silver heatsink) to trimpots, bias adjust the voltage of the tube to the required amount, there are reference charts for the 12v triode tubes you can adjust the bias to, this will provide a more balance to the sound and certainly can reduce any slight voltage swings and extra heat on those IRL520's.

For tube rolling, I definitely recommend you trying Sylvania O getter (black or grey plates), they mix in with the sound of the those IRL520's very good. 

DefQon, thanks mate :) Will do that :)

Sorry, I made a mistake in the last post, if your going to change the power cap to a 35v make sure its 3500uf not 6800.

Is there a pictorial or a list of parts I have to change to get the most out of my Bravo Audio V2? Received mine today and I am not pleased with the sound compared to my Fiio E17.

I use a Behringer UCA222 DAC