Bravo Audio - funny looking little tube amps
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Mshenay

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I've just noticed listening to a metal album through this amp, that there is bleed over to the left channel when a guitar riff is supposed to be just on the right.  It sounds like it's distorted and bleeding over to the other side.  This surely isn't right?  Does anyone know what this issue may be?
 
Thanks in advance.
if the bass boost is on that would be the issue. The boost increases the voltage. I've actually measured during before and amp using bass boost and it does boost the bais by avout .2 volts so if one side slighty higher thant he other the bass boost would compound it, also is your tube a balanced tube. 
 
Still I have that issue every so often, just check ur bias and re blance the tube. That should work! 
 
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amigomatt

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Quote:
I've just noticed listening to a metal album through this amp, that there is bleed over to the left channel when a guitar riff is supposed to be just on the right.  It sounds like it's distorted and bleeding over to the other side.  This surely isn't right?  Does anyone know what this issue may be?
 
Thanks in advance.
if the bass boost is on that would be the issue. The boost increases the voltage. I've actually measured during before and amp using bass boost and it does boost the bais by avout .2 volts so if one side slighty higher thant he other the bass boost would compound it, also is your tube a balanced tube. 
 
Still I have that issue every so often, just check ur bias and re blance the tube. That should work! 

Thank you for your help. I'm using the Bravo Audio Ocean. There's no bass boost on it and I'm running it straight from the pre out of an Arcam integrated amp, so no boost of any kind there either.

I'm sorry, I'm a total noob with tubes and this is my first one. Do you have a link to any info about whether my tube is balanced/how to balance it etc.?! I'll go searching...
 
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DefQon

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You can balance the bias supply to both channels usually 12.5-13v for the 12AU7. That mean's you'd need to open the top half of the enclosure and using a multimeter to few a few resistor points near the LM317 mosfets. I think it voids warranty, but you can buy another 12AU7 tube and see if the bleeding is still present. The supplied Chinese tubes are that great. Even a $5 GE or RCA will sound better but offering different sound signatures. But I seriously doubt Bravo didn't balance these properly for you, another problem could also be the volume pot.
 
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amigomatt

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You can balance the bias supply to both channels usually 12.5-13v for the 12AU7. That mean's you'd need to open the top half of the enclosure and using a multimeter to few a few resistor points near the LM317 mosfets. I think it voids warranty, but you can buy another 12AU7 tube and see if the bleeding is still present. The supplied Chinese tubes are that great. Even a $5 GE or RCA will sound better but offering different sound signatures. But I seriously doubt Bravo didn't balance these properly for you, another problem could also be the volume pot.
Thanks again for your help.  I've just won this tube on ebay, seemed like a good deal?  I'll see how that goes before getting a multimeter and start learning how to tinker around inside!
 
http://www.ebay.co.uk/itm/1x-MULLARD-ECC82-12AU7-B329-VINTAGE-RADIO-VALVE-VALVES-TUBES-/261185244722?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWNX%3AIT&nma=true&si=Saz2lICiN7%252BnCD1RMqOtzLje7Iw%253D&orig_cvip=true&rt=nc
 
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DefQon

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Yes Mullards are quite good, warm with good low-end bass. Beware of modern Russian re-issues, they don't sound as good as the old NOS.
 
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amigomatt

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Yes Mullards are quite good, warm with good low-end bass. Beware of modern Russian re-issues, they don't sound as good as the old NOS.
Glad to hear that about the bass, that's exactly what my K240 DFs need!  How does one tell if they are modern Russian re-issues?  Do they look the same?
 
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Glad to hear that about the bass, that's exactly what my K240 DFs need!  How does one tell if they are modern Russian re-issues?  Do they look the same?
Usually sellers don't try to cheat you, you can ask about what year they were made. Generally you want stuff from before the 90's.
I'm not a pro with the 12AU7 tubes (wouldn't call myself a pro with the 6DJ8 type tubes/valves I buy, but I have learned over the past half year), but that Mullard looks pretty good. Generic box, but the worn label on the tube itself doesn't scream "FAKE!" to me, and if the test numbers are accurate the tube should work like new and not have a perceptible channel imbalance. Should sound good so long as it wasn't physically damaged or compromised. I bet you'll love it. Some day, you may want to try a leaner, more energetic tube too, just to have the option :)

The tube that came with my amp came smashed, and the Amperex I first bought to try was warm but seemed to have a channel imbalance. I got a military-spec tube after that which was leaner & more energetic, I was amazed (& addicted instantly) by the detail retrieval and soundstage depth. Just recently I bought a pair of Amperex with the little bugle-blowing tube cartoon on it and four New Old Stock (NOS) Vokshod tubes from the 70's, haven't tested them all yet because I'm enjoying the first Bugle Boy I put in (which doesn't sound THAT much different from the Mil-spec tube I used before)

The Electro Harmonix that (I believe) came with your Ocean is a current production Chinese manufactured tube... Some people like 'em, but really they aren't held to high production standards and may account for the sound crossing over to the other channel. Hopefully it isn't an issue from the amp itself, I guess you're about to find out. Good luck man! :)


Edit: Oh yes, DefQon mentioned biasing and using a multimeter, and you said you were a n00b. Basic explanation:
Inside your amp, there is probably two little components (called Potentiometers) with little screwdriver adjustment pins. Turn these to adjust how much voltage goes to each channel of the Tube, you want both channels equal at somewhere between 12.5 and 13 volts. You measure those volts using a multimeter, here's mine:

I got mine from Amazon for about $6 USD, works well enough for me. Those red & black wires with pins on the end are the test leads, you touch them to the part of the circuit path you are adjusting to get a reading (amp has to be turned on & warmed up, I turn on my multimeter by turning the dial to the 20 volt DC setting). I don't know where to take a reading on the Ocean, sorry. You could try tuning the tube by ear, I tried that but I couldn't get it to sound right (probably messed up my first Amperex tube that way too), using the Multimeter made a big difference.

Again, good luck! Hopefully that helped, and you now know what to search the 'net for to answer other questions.
 
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DefQon

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Glad to hear that about the bass, that's exactly what my K240 DFs need!  How does one tell if they are modern Russian re-issues?  Do they look the same?
Since the Russian reissues are current modern day in production tubes manufactured in Russia strictly according to Mullards spec sheets and QC testing, sellers on ebay will usually say re-issue or Russian re-issue on the description page or the title of the item being sold. If you're experienced with identifying tubes and the variances (which I am not) one can tell and compare from the logo printing/etched on the tube or date codes or part codes etched. Usually it will say Made In Russia on the tube though. Similar to my Gold Lion re-issues (duds now).
 
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DefQon,
There are some current production tubes that sound pretty great though, right? Of course, they cost a lot more than the vintage tubes, and I don't think they outperform the rarer tubes from the heyday of tube audio.
 
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DefQon

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DefQon,
There are some current production tubes that sound pretty great though, right? Of course, they cost a lot more than the vintage tubes, and I don't think they outperform the rarer tubes from the heyday of tube audio.
The best current production 12AU7 tubes which is the only 12**7 variant tube of the dual triode family that I have a lot of experience with (but not a pro) today is the grade A Sophia and Psvanes, it knocks the socks easily off the vintage Holland Bugle Boys I had and gave the Telefunken smooth plates a run for it's money which is the second best lot of the Tele's money can buy NOS grade apart from the European military variant Telefunken's which costs a leg and arm to afford.
 
Although the Psvanes and Sophia's don't come cheap as well $100 a tube, it does indeed easily best any of the cheap and expensive NOS I've tried only to ever lose to a rare unidentified Amperex my friend had which he said cost $250 for 1 tube, he still won't tell me what they are exactly and I'm betting my money that it's some rare-ass Bugle Boy from as early as 1940's, he runs a quad, 2 pair each in a pair of $35000 monoblocks he uses for his horns. 
 
People tend to stay away from modern re-issues and stick by the good old statement that the older, the better i.e. NOS > reissues. This is not the case, a lot of people that use to run NOS Gold Lion 6DJ8's which cost heaps of $$$ would even agree the reissues sound almost identical, in some cases even better than the NOS, all comes down to the application and amplifier being used. 
 
Although I have not tried many Russian reissues for the 12AU7 family, the EL84's I have, for example, the reissue Mullards and Philips sound better than the NOS grade Britain made Mullard and the Philips manufacture for 1970's Valvo, although the differences are not great, it's notable. There is no reason to think that reissues shouldn't sound better than NOS, with newer tech/equipment and better ways of fabricating valve tubes, and NOS supply running low as demand and interest continously grows, it will be a matter of time (not anytime soon though) that modern reissues will take over NOS variants.
 
My 2c.
 
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Mshenay

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Thanks again for your help.  I've just won this tube on ebay, seemed like a good deal?  I'll see how that goes before getting a multimeter and start learning how to tinker around inside!
 
http://www.ebay.co.uk/itm/1x-MULLARD-ECC82-12AU7-B329-VINTAGE-RADIO-VALVE-VALVES-TUBES-/261185244722?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWNX%3AIT&nma=true&si=Saz2lICiN7%252BnCD1RMqOtzLje7Iw%253D&orig_cvip=true&rt=nc
i have one of those in my millet hybrid amp, they are a nice tube! Very warm and thick though, make sure to use them with a very lean can for an epic paring ^^ 
 
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Judge Buff

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yea ignore Buff he's a cranky old fart ;3. Although he knows his tubes xD so he's always a joy to listen to... unless ofc he's giving us whimper snappers some life leassons lol [kiddin with ya buff <3 <3] 
Bwahahaha! Old fart? You bet. Don't get downwind... Whimper snappers?

I have what I think is a cheap RCA 12ua7a Clear Top tube in my indeed G3, and it sounds really wondeful!

Great tight bass, smooth highs, lush punchy mids and awesome sound stage. My w1000x really lobes my indeed <3 <3

I thought you'd appreciate the clear-top sound... Good all round listening tube; smooth as silk panties :-o

Amigomatt's Mully is the real deal. If it is close to balanced and biased right, it is addicting for vocals, especially ladies! Good Mullies are like eating honey on an English muffin: really yummy, but really rich. The advice re brighter cans may be dead on, if it's too dark.

Hey y'all, I asked Evshrug to canvass for restarting the Indeed thread. I think that while these amps are the same basic design, the G2/G3 are a better deal than any Bravo unit and especially that crappy EQ model. (No offense to any owners). Lecky (an awesome Brit Indeed owner) had (has?) a thread out there. I should have split off in 2010, but it was just easier to post in the Bravo thread. If any Indeed folks want to start up a new thread, I'll support it.

Cheers!
 
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Mshenay

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Bwahahaha! Old fart? You bet. Don't get downwind... Whimper snappers?
I thought you'd appreciate the clear-top sound... Good all round listening tube; smooth as silk panties :-o

Amigomatt's Mully is the real deal. If it is close to balanced and biased right, it is addicting for vocals, especially ladies! Good Mullies are like eating honey on an English muffin: really yummy, but really rich. The advice re brighter cans may be dead on, if it's too dark.

Hey y'all, I asked Evshrug to canvass for restarting the Indeed thread. I think that while these amps are the same basic design, the G2/G3 are a better deal than any Bravo unit and especially that crappy EQ model. (No offense to any owners). Lecky (an awesome Brit Indeed owner) had (has?) a thread out there. I should have split off in 2010, but it was just easier to post in the Bravo thread. If any Indeed folks want to start up a new thread, I'll support it.

Cheers!
Same here, the bravo is terribad b ut a popular thread. I started a new thread or better yet I made a review, we can use my review thread and continue it forward like a lot of ppl do
 
interesting enough, the clear top is STILL warmer than the LEAN solid state I got. So that's nice! I'm w8ing for the L3k pads for my w1kx the pads are spoused to make the can warmer, so it should pair nice with the ss
 
alsoi the dt 880 sounds REALLY nice out of the ss :O warmer than it does out of my THICK tube e.e
 
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Forgive me if this has already been answered, but with a 129 pages devoted to the Bravo, I've not been able to find it.
 
I just received a V2 today and guess I got lucky, because it is dead quite (no static).  My question is, the stock tube does not glow at all from what I can see.  In other words, I have a Cary tube system as my main home audio system and those tubes obviously glow orange.
 
I have looked at the stock tube on the Bravo V2 and I see zero glow from the heaters.   The blue LED is bright, but it would not "drown out" any glow from the tube if looked at closely.
 
Thanks very much all
 
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Mshenay

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Forgive me if this has already been answered, but with a 129 pages devoted to the Bravo, I've not been able to find it.
 
I just received a V2 today and guess I got lucky, because it is dead quite (no static).  My question is, the stock tube does not glow at all from what I can see.  In other words, I have a Cary tube system as my main home audio system and those tubes obviously glow orange.
 
I have looked at the stock tube on the Bravo V2 and I see zero glow from the heaters.   The blue LED is bright, but it would not "drown out" any glow from the tube if looked at closely.
 
Thanks very much all
... buy a cheapo tube n see if it glow orange :O
 
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