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Bravo Audio - funny looking little tube amps - Page 131

post #1951 of 2605
YGPM

 

Quote:
Originally Posted by DefQon View Post

Quote:
Originally Posted by rmouser View Post

Defqon--the "trickery" you refer to is obviously the new Starlight. there are 3 guys on the planet with knowledge, me being the least as I built the very first kit. The designers are very highly respected.

 

 

Hmm sorry no I didn't, I think you have a misunderstanding here? The Starlight didn't even come to mind when I made my post, actually didn't even know the Starlight after I made the post on your Starlight thread. I was talking about few of the low budget and high end "tube buffered" CD players and amplifiers I have read and owned. Namely one of them is my $1k Shanling CD300, the opamp's do the work and the tube is only for cosmetic purposes but all that was changed after following the procedures of getting it Lampized.

post #1952 of 2605

tongue.gif

 

About to get a 6SN7 adapter to 12AU7, going to use my Bravo as a test rat to see how it performs since I have a load of 6SN7 tubes from DV amp.

post #1953 of 2605
I'm noticing distortion appearing when the volume level is above 10 o'clock on certain tracks. I'm using a used Mullard valve from ebay. I had the same issue with the stock valve to an even worse degree, so I opened the amp up with the intention of adjusting the bias pot. I couldn't find one on the board, so I'm presuming I can't adjust that. Is that correct? Here is the inside of the amp:

post #1954 of 2605

None of the Bravo amp's have trim pots for bias adjustment. They are biased from the factory. Distortion doesn't sound like it is a bias problem, if you were experiencing massive channel imbalance than that would be unbalanced bias adjustment for the heater currents at 12.5-12.6v for each channel. 

 

Check for any broken solder contacts or bad solder contacts where there shouldn't be, one of the mosfets could be faulty or badly soldered, missing or inappropriate valued resistors either in series or parallel, volume pot problem/bad solder, bad cap, psu, bad ground or lifted ground etc....To many factors to list, before you opened your Bravo Ocean up and if still under warranty you should've gotten fixed via warranty support from Bravo themselves rather than taking on your own initiative of trying to identify the problem which difficult without the right equipment or knowledge.

post #1955 of 2605
Quote:
Originally Posted by DefQon View Post

None of the Bravo amp's have trim pots for bias adjustment. They are biased from the factory. Distortion doesn't sound like it is a bias problem, if you were experiencing massive channel imbalance than that would be unbalanced bias adjustment for the heater currents at 12.5-12.6v for each channel. 

Check for any broken solder contacts or bad solder contacts where there shouldn't be, one of the mosfets could be faulty or badly soldered, missing or inappropriate valued resistors either in series or parallel, volume pot problem/bad solder, bad cap, psu, bad ground or lifted ground etc....To many factors to list, before you opened your Bravo Ocean up and if still under warranty you should've gotten fixed via warranty support from Bravo themselves rather than taking on your own initiative of trying to identify the problem which difficult without the right equipment or knowledge.

Given that you have to open it up to change the tube, does changing the tube invalidate the warranty too, then?
post #1956 of 2605

Hi All,

 

Thought of sharing some pictures of the mods which I did on my Bravo Audio Ocean.

 

I replaced the stock parts with the following in the amp -

 

1. Replaced the stock capacitors with higher quality Panasonic caps with higher voltage rating (35V & 25V) for the power filter section and with higher capacitance (3300uF & 2200uF)

2. Replaced the stock MOSFET transistor with the IRF 510 

3. Stock tube with a collection of NOS tubes

 

The up-gradation of the capacitors have added more weight to the lows and helps the amp provide more juice during the busy passages in the music.

The IRF 510 MOSFET has opened up the highs considerably and one can feel the improvement immediately. 

These tweaks have helped churning out a balanced sound signature from the otherwise mid-centric little amp. The downside is that the top cover of the amp doesn't fit anymore because of the size of the capacitors but it is helping with improved ventilation (I am an optimist with "B-Positive" blood group wink.gif)

 

I have been trying out the different NOS tubes and feel that all of them handles the music differently and adds its own color to it. The clear tops have overall better "feeling" to the music.

 

Before the surgery-

 

 

 

After Surgery -

 

 

 

 

The great family picture -

 

 

Enjoy!

post #1957 of 2605
Quote:
Originally Posted by viveksaikia22 View Post

Hi All,

Thought of sharing some pictures of the mods which I did on my Bravo Audio Ocean.

I replaced the stock parts with the following in the amp -

1. Replaced the stock capacitors with higher quality Panasonic caps with higher voltage rating (35V & 25V) for the power filter section and with higher capacitance (3300uF & 2200uF)
2. Replaced the stock MOSFET transistor with the IRF 510 
3. Stock tube with a collection of NOS tubes

The up-gradation of the capacitors have added more weight to the lows and helps the amp provide more juice during the busy passages in the music.
The IRF 510 MOSFET has opened up the highs considerably and one can feel the improvement immediately. 
These tweaks have helped churning out a balanced sound signature from the otherwise mid-centric little amp. The downside is that the top cover of the amp doesn't fit anymore because of the size of the capacitors but it is helping with improved ventilation (I am an optimist with "B-Positive" blood group wink.gif
)


I have been trying out the different NOS tubes and feel that all of them handles the music differently and adds its own color to it. The clear tops have overall better "feeling" to the music.

Before the surgery-





After Surgery -










The great family picture -




Enjoy!


Inspiring!
post #1958 of 2605

Don't use IRF510, they are no different to IRF530/630's. Use IRL510/530's, these babies are the ones that make a difference to the highs.

 

And no tube rolling doesn't void the warranty to my knowledge. Bravo is pretty stupid to put a tube guard on top of the enclosure.

post #1959 of 2605
Quote:
Originally Posted by rmouser View Post

 

mshenay---you're referring to me as the devil is NOT quite appropriate on a forum like this...............

 

Excuse me but how so, that was in NO way a negative comment lol. I LOVE my G3 and I'm very happy to have purchased from you. I used the term devil in a joking manner lol. The "devil" tempts you and that G3 was TEMPTING and I BIT and Now I'm HOOKED on hybrid tubes [again all positives] 

 

But yea that was a compliment, lol nothing negative on your part. I don't see how it was inapproriate seeing as the connetation is entirely postive there. Non teh less I do apologize for the comment

 

Non the less, any one know a good place to get a wood siding for the G3, as I'd love to add that into mine! 

post #1960 of 2605
Quote:
Originally Posted by viveksaikia22 View Post

I have been trying out the different NOS tubes and feel that all of them handles the music differently and adds its own color to it. The clear tops have overall better "feeling" to the music.

 

Totally, I have Clear Tops in both of my Hybrid Tubes and I enjoy them very much! the w1000x sounds WONDERFUL with clear tops 

post #1961 of 2605

Mshenay have you tried any upper range tubes besides those cheap RCA clear tops?

post #1962 of 2605
Quote:
Originally Posted by DefQon View Post

Mshenay have you tried any upper range tubes besides those cheap RCA clear tops?

not yet, to broke to get teh good tubes atm

 

suggestions though? 

post #1963 of 2605

Oh the irony in that. rolleyes.gif

 

What headphones you using out of your G3?

post #1964 of 2605
Quote:

Originally Posted by Mshenay View Post
 

.........

 

Non the less, any one know a good place to get a wood siding for the G3, as I'd love to add that into mine! 

 

Try out Joanne. They have some bass wood planks on sale. These are very easy to work on and can take on any polishing....

post #1965 of 2605
Quote:
Originally Posted by DefQon View Post

Don't use IRF510, they are no different to IRF530/630's. Use IRL510/530's, these babies are the ones that make a difference to the highs.

 

And no tube rolling doesn't void the warranty to my knowledge. Bravo is pretty stupid to put a tube guard on top of the enclosure.

 

I searched out for the IRL510s but didn't find them as all are just sold off and the places were they are available are overpriced.

But the IRF510 are for sure more brighter than the stock IRF630.

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