[money4me247]

'all 3 EQ turn to highest means unequalised. this is the characteristic of "passive EQ" which equiped by the Bravo V3.' (Bravo Technician)

this shld be right based on how the amp is designed.

 

[money4me247]

I have to strongly disagree with this statement. The correct flat setting is at the middle position which have indents you can feel when moving the sliders. I have tested with several DACs and several headphones and it is clear to me that the sound is audibly flat with all sliders in the middle position. All EQ's since the dawn of HiFi time have worked this way. There is no EQ I have encountered in 40 years of HiFi experience that works with the flat setting with all sliders at the top. Of course, the posters unit may be defective which I cannot comment on. I am using a Bravo V3 that I obtained in March 2015 through Massdrop. Additionally, with all the sliders at the top the gain is much higher which makes the volume control almost useless because of limited travel before attaining ear bleed level. Please use the middle position as a start and then adjust for preference from there.

the middle may sound the most neutral to your ear since you are comparing against the other two positions, but the passive eq design actually makes the top setting unequalized, and then each step down equalizes the sound and cuts down on the specific frequency band

 

[Didhefocus]

  I have to strongly disagree with this statement. The correct flat setting is at the middle position which have indents you can feel when moving the sliders. I have tested with several DACs and several headphones and it is clear to me that the sound is audibly flat with all sliders in the middle position. All EQ's since the dawn of HiFi time have worked this way. There is no EQ I have encountered in 40 years of HiFi experience that works with the flat setting with all sliders at the top. Of course, the posters unit may be defective which I cannot comment on. I am using a Bravo V3 that I obtained in March 2015 through Massdrop. Additionally, with all the sliders at the top the gain is much higher which makes the volume control almost useless because of limited travel before attaining ear bleed level. Please use the middle position as a start and then adjust for preference from there.

The sliders are probably off-the-shelf parts and come with center detents, no custom parts in this budget amp! About your comment on the gain being too high with the EQ sliders all up...my inefficient Yamaha HP-2 headphones don't play even close to loud unless the sliders are all up. If you look at this thread near the beginning you'll see my EQ bypass mod. The V3 sounds most close to bypass with all the sliders UP! I also have a Little Bear P1 which is identical to the V1 except with some minor enhancements like a relay to eliminate turn-on thump, larger heat sinks for better heat dissipation and dual tube voltage switch for tube rolling options, but basically the same amp. The V3 sounds identical to the Little Bear P1 when the EQ is bypassed! You're not alone when you say you never saw an EQ that is flat with all sliders all the way up, but if you really think about it...it can't be any other way with a passive circuit. The sliders are simply potentiometers (variable resistors) that cut the voltage in the frequency range assigned to it. Without an active circuit with gain amplifiers there's no way to boost so all you can do is cut or attenuate the sound. The headphones you're using must be very efficient, mine vary and I don't listen at excess levels. I haven't had any problem getting the right volume on any of them with 9 o'clock to noon being the range of the knob position. Anyway don't sweat it and enjoy your new V3!
 

 

[Didhefocus]

My V3 is now shutting down after about 5 minutes. Plays fine sounds great then pop, no sound, lights out. A few minutes later, after cooling it's ready to go again. Tried different tube and putting back the 1000uf caps which were upgraded to 2200uf. Still the same! Any opinions on what to try next?

 

[ctbarker32]

 
The sliders are probably off-the-shelf parts and come with center detents, no custom parts in this budget amp! About your comment on the gain being too high with the EQ sliders all up...my inefficient Yamaha HP-2 headphones don't play even close to loud unless the sliders are all up. If you look at this thread near the beginning you'll see my EQ bypass mod. The V3 sounds most close to bypass with all the sliders UP! I also have a Little Bear P1 which is identical to the V1 except with some minor enhancements like a relay to eliminate turn-on thump, larger heat sinks for better heat dissipation and dual tube voltage switch for tube rolling options, but basically the same amp. The V3 sounds identical to the Little Bear P1 when the EQ is bypassed! You're not alone when you say you never saw an EQ that is flat with all sliders all the way up, but if you really think about it...it can't be any other way with a passive circuit. The sliders are simply potentiometers (variable resistors) that cut the voltage in the frequency range assigned to it. Without an active circuit with gain amplifiers there's no way to boost so all you can do is cut or attenuate the sound. The headphones you're using must be very efficient, mine vary and I don't listen at excess levels. I haven't had any problem getting the right volume on any of them with 9 o'clock to noon being the range of the knob position. Anyway don't sweat it and enjoy your new V3!
 

Could you please read this link about the difference between active and passive eq. I cannot find anywhere your repeated comment that passive eq can only cut and cannot boost. The way you have characterized the Bravo V3 eq just doesn't make any logical sense and would seem pointless to implement if it was. If I push all the sliders to max as I say the volume control is nearly useless.
 
I own nearly all the highly rated headphones under $1k including Sennheiser 700, 650, HiFi Man 400i, BeyerDynamic 880 250 ohm, Oppo PM-2, Shure 1840, and on and on. I am listening to BeyerDynamic 880 250 ohm right now from my computer to a brand new Shiit Modi 2 out to the Bravo V3. I am getting very loud levels at barely 11 o'clock with eq faders at their middle indent setting. Pushing the faders to their max would be at ear bleed level.
 
You only mention the Yamaha headphones which seem to be from about 2002? You should definitely test with some more recent phones?
 
I am not unfamiliar with audio circuitry although I am an amateur for some 40 years. I've built kits from Hafler and PS Audio. I just finished building 3 kits - Hagerman Labs Comet3, Piccolo2 and a Bottlehead Crack OTL Headphone Amp. When comparing the sound of the Crack to the Bravo 3, the Bravo 3 sounds most similar to the Crack when the EQ sliders are at their middle indent position.
 
I guess we will have to agree to disagree about this but I think it is important that other readers understand other points of view.
 
-CB

 

[money4me247]

  Could you please read this link about the difference between active and passive eq. I cannot find anywhere your repeated comment that passive eq can only cut and cannot boost. The way you have characterized the Bravo V3 eq just doesn't make any logical sense and would seem pointless to implement if it was. If I push all the sliders to max as I say the volume control is nearly useless.
 
I own nearly all the highly rated headphones under $1k including Sennheiser 700, 650, HiFi Man 400i, BeyerDynamic 880 250 ohm, Oppo PM-2, Shure 1840, and on and on. I am listening to BeyerDynamic 880 250 ohm right now from my computer to a brand new Shiit Modi 2 out to the Bravo V3. I am getting very loud levels at barely 11 o'clock with eq faders at their middle indent setting. Pushing the faders to their max would be at ear bleed level.
 
You only mention the Yamaha headphones which seem to be from about 2002? You should definitely test with some more recent phones?
 
I am not unfamiliar with audio circuitry although I am an amateur for some 40 years. I've built kits from Hafler and PS Audio. I just finished building 3 kits - Hagerman Labs Comet3, Piccolo2 and a Bottlehead Crack OTL Headphone Amp. When comparing the sound of the Crack to the Bravo 3, the Bravo 3 sounds most similar to the Crack when the EQ sliders are at their middle indent position.
 
I guess we will have to agree to disagree about this but I think it is important that other readers understand other points of view.
 
-CB

 
@Didhefocus is correct.
 
The sliders are simply potentiometers (variable resistors) that cut the voltage in the frequency range assigned to it. 
 
"A potentiometer is an adjustable resistor which consists of a wiper that slides across a resistive strip to deliver an increase or decrease in resistance. The level of resistance will determine output of current to the circuit"
 
The Bravo V3 does not have a programmable-gain, so there is no way to boost. A programmable-gain amplifier (PGA) is an electronic amplifier (typically an operational amplifier) whose gain can be controlled by external digital or analog signals.
 
The way the Bravo V3 works is that sliders maxed out is no EQ engaged and you are fully amplifying your signal. Then slider down one notch applies resistance to the circuit that cuts the amount of voltage to a specific frequency range. Slider down two notches applies more resistance and decreases the amount of voltage to that specific frequency range even more.
 
Whether you prefer the sound of middle sliders or top sliders is a personal thing, but sliders all the way up is unEQed. 

 

[Didhefocus]

The first two paragraphs in your link are very clear of what we are trying to explain.

Most forms of audio equalisation are inherently 'lossy' processes in terms of signal level, and simple filter circuits are actually frequency-selective attenuators; they reduce the signal level above or below a frequency determined by the component values. So if you want to make a simple cut-only equaliser (as shown in the top diagram, right), it can be done quite easily with purely passive components (capacitors, inductors and resistors), all carefully chosen to provide the desired turnover frequencies and slopes. With this kind of design, power is not needed at all, but the type of equalisation that can be achieved is limited to simple high- and low-pass filters, and basic band-pass filters with gentle slopes.
The loss of signal level through a purely passive filter stage is often undesirable, and the turnover frequencies and slopes may be affected by the impedances of the source and destination equipment. For these reasons it is common practice to incorporate transformers and buffering amplifiers to help guarantee consistent performance, and to compensate for losses through the filters. In this case, although the equalisation itself is still passive, power will be required for the amplifiers that are present in the circuit.

The only thing they don't mention is the position of the sliders for flat response.

 

[sasquatch98]

Could you please read this link about the difference between active and passive eq. I cannot find anywhere your repeated comment that passive eq can only cut and cannot boost. The way you have characterized the Bravo V3 eq just doesn't make any logical sense and would seem pointless to implement if it was. If I push all the sliders to max as I say the volume control is nearly useless.

I own nearly all the highly rated headphones under $1k including Sennheiser 700, 650, HiFi Man 400i, BeyerDynamic 880 250 ohm, Oppo PM-2, Shure 1840, and on and on. I am listening to BeyerDynamic 880 250 ohm right now from my computer to a brand new Shiit Modi 2 out to the Bravo V3. I am getting very loud levels at barely 11 o'clock with eq faders at their middle indent setting. Pushing the faders to their max would be at ear bleed level.

You only mention the Yamaha headphones which seem to be from about 2002? You should definitely test with some more recent phones?

I am not unfamiliar with audio circuitry although I am an amateur for some 40 years. I've built kits from Hafler and PS Audio. I just finished building 3 kits - Hagerman Labs Comet3, Piccolo2 and a Bottlehead Crack OTL Headphone Amp. When comparing the sound of the Crack to the Bravo 3, the Bravo 3 sounds most similar to the Crack when the EQ sliders are at their middle indent position.

I guess we will have to agree to disagree about this but I think it is important that other readers understand other points of view.

-CB

I've currently got a bravo V2 I'm using with an assortment of NOS tubes with my HD580s. I've been having static most likely from a bad solder joint and I'm considering sending the amp back and ordering a bottlehead crack kit do to concerns about the longevity of the bravo. What are your thoughts on the crack vs the bravo v series sound quality wise?

Thanks

 

[Didhefocus]

I've currently got a bravo V2 I'm using with an assortment of NOS tubes with my HD580s. I've been having static most likely from a bad solder joint and I'm considering sending the amp back and ordering a bottlehead crack kit do to concerns about the longevity of the bravo. What are your thoughts on the crack vs the bravo v series sound quality wise?

Thanks

Sorry no experience with the bottlehead crack. Actually, never heard of it! 
These Bravos all sound bad unless modified. They're hobbyist toys IMO. If you don't like soldering and modding, the Bravo probably isn't for you!

 

[Sam21]

How strong does the Bass get by EQing the Bass ? 
 
Also, can someone please tell me which class of tubes are compatible with this amp ?
 
 
Many thanks

 

[Didhefocus]

To boost bass on this amp you lower the mid and treble sliders. The strength will depend on your headphones and how loud you listen.

 

[Sam21]

Passive EQ only cuts the signal down ? doesnt boost it ?

 

[Sam21]

Let me clarify what I mean :
 
Flat setting is the max setting, you can't boost the Bass more than the max(Flat) setting ?

 

[Didhefocus]

Let me clarify what I mean :

Flat setting is the max setting, you can't boost the Bass more than the max(Flat) setting ?

Correct.
By cutting the other 2 sliders you have in effect boosted the third one. The problem is that you loose gain and it doesn't go as loud as before!

 

[Manjerico]

Hi guys. I've been using a Bravo Audio V3 with AKG's K702 and I since I know very little about tubes and tube rolling I was wondering what better tubes are for music (Hard Rock, some EDM, Jazz and classical) and for gaming. My main goal with the "gaming tubes" is to have the best soundstage possible so I better pinpoint the location from where the sounds are coming from.
 
Thanks.