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Bravo Audio - funny looking little tube amps - Page 176

post #2626 of 2637
Quote:
Originally Posted by amigomatt View Post
 

Between those two, I would recommend the Beyerdynamic as the 32ohm or 250ohm would be much easier to drive than the K702.  I found the K702 really picky in terms of amping.  I only kept them for a couple of weeks.

 Thanks for the recommendation. I see you have the HE400's how does the ocean do powering those? I know its a completely different sound just curious. 

post #2627 of 2637
Quote:
Originally Posted by Mhumbach View Post

Quote:
Originally Posted by amigomatt View Post

 
Between those two, I would recommend the Beyerdynamic as the 32ohm or 250ohm would be much easier to drive than the K702.  I found the K702 really picky in terms of amping.  I only kept them for a couple of weeks.
 Thanks for the recommendation. I see you have the HE400's how does the ocean do powering those? I know its a completely different sound just curious. 
I would say that, despite it sounding smooth and warm, which is good for the he400, it still doesn't have quite enough oomph to drive them to loud enough levels for me without distorting with some music.
post #2628 of 2637
Quote:
Originally Posted by amigomatt View Post


I would say that, despite it sounding smooth and warm, which is good for the he400, it still doesn't have quite enough oomph to drive them to loud enough levels for me without distorting with some music.

Sounds good thanks. I know my turntable amp would be able to power all these but i'm going to use the ocean to power my digital collection. Ill keep my search up for a suitable phone.

post #2629 of 2637
Quote:
Originally Posted by Mhumbach View Post
 
Quote:
Originally Posted by amigomatt View Post


I would say that, despite it sounding smooth and warm, which is good for the he400, it still doesn't have quite enough oomph to drive them to loud enough levels for me without distorting with some music.

Sounds good thanks. I know my turntable amp would be able to power all these but i'm going to use the ocean to power my digital collection. Ill keep my search up for a suitable phone.

Yeah, they power my Grado SR80, NAD HP50, Sennheiser HD598 etc all wonderfully.  I love having the option of that tube sound as well.  Good luck!

post #2630 of 2637
Quote:
Originally Posted by RFtech53 View Post
 

USAstrat,

 

Thanks for your post. My wife gave me a V2 for Christmas today along with AudioTechnica ATH-M50's. I love the little amp, but I was also getting the intermittent ticking noise. My cell phone has only been about 10 inches away. I'll have to try what you said to see if it goes away.

 

My background has been over 40 years in electronic repair and engineering. I spent 20+ years repairing electronic musical instruments and was authorized by companies such as Fender, Marshall, Peavey and others. In all those years, I've heard tube amps do some crazy things ... but never rhythmic ticking.  :-)   

 

I'm hoping getting the cell phone away takes care of things. I'm even a licensed FCC General Class RadioTelephone Operator, but don't know if cell phone interference ever would have occurred to me. 

 

The Bravo amps are completely un-shielded, so you should expect that any kind of transmitter, like your cell phone, will induce RFI in the unit. This should come as no surprise to an electronic technician. There is nothing wrong with the amplifier.

 

Personally, I like the indication that comes from the RFI because it tells me I'm about to get a phone call or a text message.

 

Move the phone a couple feet away and it will stop.

post #2631 of 2637
Quote:
Originally Posted by pezhore View Post
 

I'm not sure if this is the best place to ask, but I prior to performing the crosstalk mod on my newly arrived Bravo V2, I was getting significant distortion sounds in the right side when panned to the left, and distortion/music in the left side when panned all the way to the right. After the crosstalk mod, the distortion in the right has gone completely, but I'm still not getting complete isolation of my left channel when panning to the right.

 

Any ideas what this could be attributed to? Suggestions for addressing it?

 

You may not have totally cut the circuit traces. Take a close look at the board with a magnifying glass.

post #2632 of 2637
Quote:
Originally Posted by amigomatt View Post
 

Hi guys,

 

I posted earlier in this thread that my Bravo reaches clipping/distortion level before my preferred volume on a couple of my harder to drive cans and I was wondering if replacing the tube with a 12ax7 variant would increase my volume range as I read that the 12ax7 tubes exhibit more gain than the 12au7.  I also read that they perform different duties as well but haven't quite got to the bottom of that mystery yet being a noob where valves are concerned.  Can anyone help me?


No. Clipping means you're pushing an amp beyond its design limits. Replacing a tube will not eliminate clipping. Try using headphones with a lower impedance. Or try buying a better amp (suggest Bottlehead Crack).

post #2633 of 2637

I moved the phone away from the V2 the next day after my original post, and as you previously posted, the noise went completely away. 

 

No surprise at all from this FCC licensed technician ... though it's somewhat natural to suspect the new piece of equipment when you've never heard the same noises from anything else. Then again, what other amplifiers around a house are so open and un-shielded.

 

I'd even written the manufacturer, and he'd suggested sending me a new power brick, suspecting it was the likely source of the ticking and other weird noises.

 

Thanks again for the heads-up. 

post #2634 of 2637
RFtech,
Bravo probably suggested the power supply because a few of them had grounding issues and DID introduce background noise, but as a different kind of technician (phone software/hardware troubleshooting... All kinds of technicians in today's world!), I can confidently say that sometimes previous experience biases us into misdiagnosis. I can only hope that by the time I have as much experience as you and Cirric, I'm as gracious and curious about new things as you two!

If I recall correctly, GSM cellular like AT&T uses (and other companies) produces a little more noise, but my CDMA cellular Verizon iPhone will still cause my tube amp (Single Ended Triode tube amp, not a bravo) to produce buzzing, squeals, and clicks. I think I experimented once but I forget if the issue still happens when I turn off cellular data...

If you've got the soldering experience and enjoy tinkering with benefits, the early part of this thread is rich with mod ideas and their effects. I particularly would point out JudgeBuff's posts (just don't call him Buffy!). Larger capacitors, film resistors, trim pots, etc.
post #2635 of 2637
Quote:
Originally Posted by UmustBKidn View Post
 
Quote:
Originally Posted by amigomatt View Post
 

Hi guys,

 

I posted earlier in this thread that my Bravo reaches clipping/distortion level before my preferred volume on a couple of my harder to drive cans and I was wondering if replacing the tube with a 12ax7 variant would increase my volume range as I read that the 12ax7 tubes exhibit more gain than the 12au7.  I also read that they perform different duties as well but haven't quite got to the bottom of that mystery yet being a noob where valves are concerned.  Can anyone help me?


No. Clipping means you're pushing an amp beyond its design limits. Replacing a tube will not eliminate clipping. Try using headphones with a lower impedance. Or try buying a better amp (suggest Bottlehead Crack).

Thanks for the straight up answer.  As it's not my main amp, I'll just keep it for my appropriate headphones when I want that taste of tube sound.

post #2636 of 2637
Quote:
Originally Posted by Evshrug View Post

...
If I recall correctly, GSM cellular like AT&T uses (and other companies) produces a little more noise, but my CDMA cellular Verizon iPhone will still cause my tube amp (Single Ended Triode tube amp, not a bravo) to produce buzzing, squeals, and clicks. I think I experimented once but I forget if the issue still happens when I turn off cellular data...

If you've got the soldering experience and enjoy tinkering with benefits, the early part of this thread is rich with mod ideas and their effects. I particularly would point out JudgeBuff's posts (just don't call him Buffy!). Larger capacitors, film resistors, trim pots, etc.

 

1) I use T-mobile, and when I had a Bravo V2 at work, my cell phone was kept within a foot or so of the amp. I could always tell when I was about to get a text message from one of my kids, or a phone call, because there would be a distinct pattern of noise audible over the top of whatever song I was listening to. The closer the phone was to the amp, the louder it got. At 3 feet away, the sound was practically inaudible.

 

2) I have two Bravo V2's, one modified with most of the enhancements listed earlier in this thread, and one stock. I can tell you right now that for the most part, the modifications ARE NOT worth the effort. Some day when I have the energy I shall attempt to create a new post about my adventure with modifying one of my V2's. For now suffice it to say that my modified V2 is more accurate, but has lost some of the bottom end, and was much more expensive to modify than it was worth. I am guessing that one of the capacitor mods is probably to blame, but that's only a guess.

 

When I get REALLY ambitious one day, I may replace the caps with something else, to see if I can reclaim some of the bottom end that I lost. Don't hold your breath waiting though :)

post #2637 of 2637

I bought a V2, can't wait for it. Going to make some tweaks, anyway I would ask a method to connect it to my laptop. Is it worth to buy a DAC like FiiO?

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