[project86]

  I am finding that Freid addressed the soundstage with this new V281. Much wider than the V200 that I had.

 
 
Exactly! Even in SE mode I sense a little improvement there, but balanced really shines. 

 

[Frank I]

John I can see the differences form the V200 mostly in soundstage and wish i still had one to compare to this V281.  Love the way it is sounding so far both single ended and balanced. it does well at low levels also. I havenot adjusted any of the setting as of yet.

 

[Zkadoush]

   
 
Exactly! Even in SE mode I sense a little improvement there, but balanced really shines. 

Would be interesting to know what accounts for a wider or more spacious soundstage in terms of measurable audio performance, when it comes to Amps.

Cheers

 

[Zkadoush]

@ rx79ez08

There seems to be a little missunderstanding ...

… to make more clear what we are using for volume control inside our Violectric gear:

Inside V90 you can find a nice and small potentiometer with two of the above mentioned resistors in one case.
It is the RK14 from Alps and works quite fine.


Inside all other headphone amps and PRE V630 we are using the good reputated ALPS RK 27. Here you can find each variable resistor (2 for stereo) in a separate housing, so crosstalk is very good. Also there is a 41-detent inside.
We are measuring the channel imbalance at 12 o´clock position. If it is higher than 0.3 dB it will be sorted out.

The first volume control option on V220, V281 and V630 is the remote option.
Beneath other things the volume can be controlled by pushing a remote button.
To do so, we are using a motorized RK 27 potentiometer.
Here a not so little motor through a gearbox turns the potentiometer, visible by the rotating knob. Of course there is a clutch installed so you can turn or stop the knob by hand even when the motor drive is in action.

The second volume control option for V220 and V281 is again made with the motorized RK 27 potentiometer. Same procedure as above. But this time a control voltage is generated and A/D converted to control the 128-step relais attenuator.

Yes, I know, there are more simple and cheaper ways to remotely control the volume.
But that´s the way we go …

By the way, because the volume is attenuated in the digital domain inside DAC V800 the quality of the potentiometer must not be that good. Here we are using again RK 14 from alps.
When there will be an updated version of V800 there will be also a motorized RK27 inside.
In the moment we are seeking the space inside the case to proceed )

Greetz

Fried

Hi Fried,

Yet another little question:

Does having a volume control like the one of the Benchmark DAC 2 (hybrid gain control) make Violectric's second optional volume control redundant?

How does the A/D converter of the VC2 affect the audio signal?

Cheers

 

[Megalomaniak]

Thats one thing I noticed while using the LCD-2s via Balanced mode. Soundstage was even better.

 

[Jodet]

  I am finding that Freid addressed the soundstage with this new V281. Much wider than the V200 that I had.

 
Frank, 
 
Looking forward to your comments on both the V281 and the V220. 
 
Congrats on the new website, very nice! 
 
 
http://headphone.guru/

 

[Frank I]

Mike,
 
Thank you and really enjoying it . We have sone great reviews coming this month from a gifted team of contributors.

 

[Jodet]

Some advice here please. 
 
The V281 has balanced inputs, yes?   So, it's $500 for amp over the V220 (non-balanced) and another $300 for the balanced cables.   
 
Balanced really make that much of a difference on HD800's? 
 
All comments, speculation, etc, welcome. 

 

[PleasantSounds]

  Some advice here please. 
 
The V281 has balanced inputs, yes?   So, it's $500 for amp over the V220 (non-balanced) and another $300 for the balanced cables.   
 
Balanced really make that much of a difference on HD800's? 
 
All comments, speculation, etc, welcome. 

 
Not sure where you buying your balanced cables, but I'd look for a different supplier. $40 should be enough to get decent quality XLR cables to connect your DAC with amp.
 
Whether the benefit justifies the cost difference is up to your own evaluation. But if you consider that to get that benefit you basically have two V220s in one, I don't have a problem justifying the pricing.
 
I'm using it with the HD800 in balanced mode and this pairing is very good. The difference between SE and balanced is mostly that the sounds feel more "articulate". In SE mode by comparison the impression is that some oomph is missing to deliver that finishing touch, especially with more dynamic sounds.
 
I have a feeling though that the HD800 are a bit overdampened on this amp - especially the bass does not "sound out" as expected. I'm planning to build a simple impedance adapter and see if it helps.

 

[fdg]

@ Zkadoush
 
The HGC from Benchmarks DAC 2 seems to adjust the volume of analog and digital sources in different ways.
The digital sources are controlled in a digital manner like we do it inside DAC V800.
The analog level seems to be treated by a motorized custom made potentiometer which might also serve to generate the control signal needed for the digital attenuation.
The "low impedance output attenuation" which provides up to 425 Ohms output impedance is doubtful in my opinion - but as Benchmark is regarded (also by me) as a company with highest engineering skills maybe there is a deeper reason behind.
 
The "Level 2" or "128-step relay controlled attenuation" of V220 and V281 is totally different from Benchmark´s HGC and unfortunately much more expensive to be produced.
The only thing they share is that the control voltage is made in a similar way by a motor driven potentiometer and sent to an A/D converter (in case of DAC 2 this concerns the digital volume control).
 
The A/D converter inside V220 / V281 in charge to generate the control voltage for the 128-step relay attenuator has nothing to do with any analog signal and thus will not affect the quality of the analog signal.

 

[Zkadoush]

  @ Zkadoush
 
The HGC from Benchmarks DAC 2 seems to adjust the volume of analog and digital sources in different ways.
The digital sources are controlled in a digital manner like we do it inside DAC V800.
The analog level seems to be treated by a motorized custom made potentiometer which might also serve to generate the control signal needed for the digital attenuation.
The "low impedance output attenuation" which provides up to 425 Ohms output impedance is doubtful in my opinion - but as Benchmark is regarded (also by me) as a company with highest engineering skills maybe there is a deeper reason behind.
 
The "Level 2" or "128-step relay controlled attenuation" of V220 and V281 is totally different from Benchmark´s HGC and unfortunately much more expensive to be produced.
The only thing they share is that the control voltage is made in a similar way by a motor driven potentiometer and sent to an A/D converter (in case of DAC 2 this concerns the digital volume control).
 
The A/D converter inside V220 / V281 in charge to generate the control voltage for the 128-step relay attenuator has nothing to do with any analog signal and thus will not affect the quality of the analog signal.

Thanks again for the patient explanations, Fried, much appreciated!

I too noticed that the 425 Ohm of the default 10 dB attenuator (of the DAC 2's balanced analogue outputs) is extraordinarily high. I thought maybe it had something to do with matching their AHB2 Power Amp (that now has fully detailed specs: http://benchmarkmedia.com/products/benchmark-ahb2-power-amplifier).

Would you recommend using the default 425 Ohm 10 dB attenuator - based on the output impedance - with the V281, or perhaps any of the other options (attenuator off: 60 Ohm; 20 dB attenuator: 135 Ohm)?

My main concern was that using a DAC 2 would render a V281 with VC2 option redundant, but since they are essentially different can I assume the benefits of both volume controls can be enjoyed?


Thanks again, Fried.

Schöne Grüße

 

[saxelrod92]

   
Not sure where you buying your balanced cables, but I'd look for a different supplier. $40 should be enough to get decent quality XLR cables to connect your DAC with amp.
 
Whether the benefit justifies the cost difference is up to your own evaluation. But if you consider that to get that benefit you basically have two V220s in one, I don't have a problem justifying the pricing.
 
I'm using it with the HD800 in balanced mode and this pairing is very good. The difference between SE and balanced is mostly that the sounds feel more "articulate". In SE mode by comparison the impression is that some oomph is missing to deliver that finishing touch, especially with more dynamic sounds.
 
I have a feeling though that the HD800 are a bit overdampened on this amp - especially the bass does not "sound out" as expected. I'm planning to build a simple impedance adapter and see if it helps.

I'm asking this from a relatively basic knowledge of impedance matching, but I thought the only time the impedance of the amp can affect the sound of the headphone is when the amp is too high for the headphones or when the amp is not powerful enough for a higher impedance headphone (hd 800, beyer t1). Otherwise the V281 in balanced mode puts out huge amounts of power into both ohm ratings of those headphones, how can they be overdampened? (genuine question, not a statement of opinion, if overdampening is a thing, I'd love to know how that works).

 

[project86]

In a nutshell, some people find that they enjoy HD800 from an amp with higher output impedance. It sort of loosens up the bass, making it more prominent but also not as well controlled. I have a tube amp (Icon Audio HP8) that allows me to increase output impedance with a knob, and sometimes it's a nice result on certain music.

 

[PleasantSounds]

 
I'm asking this from a relatively basic knowledge of impedance matching, but I thought the only time the impedance of the amp can affect the sound of the headphone is when the amp is too high for the headphones or when the amp is not powerful enough for a higher impedance headphone (hd 800, beyer t1). Otherwise the V281 in balanced mode puts out huge amounts of power into both ohm ratings of those headphones, how can they be overdampened? (genuine question, not a statement of opinion, if overdampening is a thing, I'd love to know how that works).

 
It's not so much about power. High impedance headphones may require higher voltage swing, but draw less current. 1V * 1A or 10V * 0.1A still is 1W.
 
The amp's output impedance has it's own purpose: to tame the electric impulses generated by the transducers when returning to their idle position. In principle this "backcurrent" is an unwanted effect and the ability to remove it completely sounds like a desirable treat. But as project86 stated, sometimes there can be too much of the good thing and letting some of it to flow through can sometimes have a positive effect on sound.
 
I have encountered on some recordings bass just going fart-fart-fart on the HD800, but not on my low impedance headphones or speakers. I'm not sure myself if increasing output impedance is going to fix this (and what side effects it's going to bring), but it's a simple experiment so why not.

 

[saxelrod92]

   
It's not so much about power. High impedance headphones may require higher voltage swing, but draw less current. 1V * 1A or 10V * 0.1A still is 1W.
 
The amp's output impedance has it's own purpose: to tame the electric impulses generated by the transducers when returning to their idle position. In principle this "backcurrent" is an unwanted effect and the ability to remove it completely sounds like a desirable treat. But as project86 stated, sometimes there can be too much of the good thing and letting some of it to flow through can sometimes have a positive effect on sound.
 
I have encountered on some recordings bass just going fart-fart-fart on the HD800, but not on my low impedance headphones or speakers. I'm not sure myself if increasing output impedance is going to fix this (and what side effects it's going to bring), but it's a simple experiment so why not.

Ok, I see how that all works now. Thank you for the useful info! It sounds like it is almost a similar situation to tubes vs. solid state, where the distortion is tubes is what makes them sound warm, just like the less technical ability of an amp to remove "backcurrent" as you say can add a bit more bass. Both are technically engineering "flaws" but are musically correct. Interesting stuff.