Parasound's Hint 6's new volume control provides huge sonic advances?


Promotional language for the (relatively) new HINT 6 says this: "New Burr-Brown Volume Control:
The Parasound HINT 6 is packed full of technical advancements. The new, upgraded volume control replaces the original model's motorized potentiometer and sliding mechanical contacts with a Burr-Brown electronically controlled analog resistor ladder volume control. Technical advancements in the new volume control offer a more distinct sound stage by increasing the dynamic range, lowering the noise floor, improving left-right separation and maintaining absolute left-right channel tracking at any volume level."

I'm not a skeptic, but am trying to learn.

QUESTION: How does a volume control affect so many elements important to the sound?

I almost never look to the details of how an amplifier's volume control is designed. Is it this important?
128x128hilde45
IF you have a very high end and very revealing system, then you will want to consider this, it would be overkill in many systems.

Regarding perfect balance, I have and use remote balance, from my listening position, as I find many recordings are a bit off, a slight tweak can make a surprisingly big difference regarding both imaging and 'opening up' the music, individual instruments properly distinct from others, an improved level of involvement.

I have 3 options for volume: manual vintage tube preamp; remote line controller (rlc) with remote volume and remote balance; remote volume of modern tube integrated amp (no balance). I use the rlc, preamp and amp preset at half volume.

Simple signal path, minimum cables .... I try/listen of options: source direct to amp, thru preamp to amp, direct to rlc then to amp, to preamp to rlc to amp. I find signal to noise the important criteria, my rlc has s/n 120db, no one can tell if it is in or out.


You have to understand that attenuation diferences between chanels will result in phase shift which will muck up imaging
It’s a good question. I do not have difficulty imagining that some devices attenuate signals more accurately than others and perhaps with less noise but how or why....who knows?
Thanks for the answers so far. I realize that attenuation must be done correctly, but I thought that would just be standard operating procedure for any amp costing $3k. The fact that Parasound is singling out this element of their design for special attention suggests that others don’t do it well enough or that Parasound  has now done it so well (compared to others) that it’s going to make a noticeable difference. I find either explanation to be pretty weak, and so there’s one more possibility, namely that their marketing people decided to tout an otherwise standard feature just to grab people’s attention. Not the kind of company I thought they were, and that's why I'm curious.
They are not the first to tout higher quality volume controls. Maybe it’s an improvement for their products. Don’t know.

I can vouch for the fact as likely could many that potentiometers in volume controls need to be kept clean else audible deterioration of the sound occurs so clearly volume controls matter.  
hilde

volume control design is absolutely critical in top quality linestages, designers have fretted and test their wiles for years to do the best sounding ones, esp. if remote control capability is involved

many attempts to innovate over time, from the melos pho-tentiometer, to the tortuga light based LDM units, to cj's relay based units, to the Polish Khozmo units that Don Sachs uses... not to mention those doing it in the digital domain -- which is fine if it doesn't lose the full bitstream resolution at lower volumes

parasound has become pretty sharp at marketing... i think this hint unit is their attempt to steal some thunder (and sales) from the successful hegels it emulates with its features set (and then some - hegels don't have phono stages built in) - i am curious if their Burr Brown volume control is such hot stuff, why is it not in their high end jc pre?  maybe it is coming in the next product cycle

Thanks, jjss49. I appreciate learning that, and it will be interesting to see whether this feature is really an advance. I know that I avoided a remote control with my own Line Stage because of advice to keep things as simple as possible. But simple is not how Parasound rolls, so this may be their way of saying, "convenience and sonic quality."

I read the older Parasound integrated amp used an old school potentiometer whereas the new one does not so that would seem to be a significant difference.
Yeah, Parasound marketing of that is more to point it out as one of the bumps from their original HALO Integrated. The Hint 6 is pretty highly regarded bang for the buck-wise.
I appreciate learning that, and it will be interesting to see whether this feature is really an advance
It’s about as much as a sonic improvement over say, the likes of an Alps Blue Velvet (-80db channel balance) as a Dact series/shunt switched resistor volume control is.
http://www.dact.com/html/attenuators.html

Nothing to write home about Burson Audio been using them for ages.
https://www.ti.com/lit/ds/symlink/pga2310.pdf?ts=1601877853848&ref_url=https%253A%252F%252Fwww.google.com%252F

Cheers George
A volume control is a voltage divider. To achieve this the sensitive signal must pass through either resistors or transformer windings. There will be two voltage dividers, one for each channel. It’s essential that these dividers achieve the same result for each channel, as the volume is varied, in order to maintain a good centred image. It is also essential that they don’t affect the signal in any way as they’re varied, ie, the sound quality is exactly the same at really low levels as at higher levels.
 If the voltage divider is a potentiometer, then the material the resistive track is made from will effect the sound quality and the two resistive tracks must match exactly. If the divider is switched resistors, this gives the opportunity to use more precise channel matching, and ‘better sounding’ resistors. If the divider is windings on a transformer, you avoid resistors all together and can achieve perfect channel matching. The only other approach, and the best I’ve yet heard, is how Lyngdorf do it, which is not to vary the music signal itself, but to vary the PSU voltage to the output driver stage.
In order of sound quality from poor to best, its Potentiometer, Switched attenuators, transformer and finally Lyngdorf’s approach.
As the volume control quality improves, the sound stage becomes more stable, sound quality more consistent from low volume to high and transparency improves.
@richtruss Thanks for that explanation -- belongs in a textbook, it's so clear! I see the kind of difference better now, and over the other range of methods. If I were comparing other options and price ranges of integrateds, I might look to see how they differed in this regard, though I still don't know the degree to which improvements in volume control  (from model to model) would matter (to my ears, at least) compared to other design elements contributing to the sound. 
Interesting thread, I do volume control completely in the digital domain which of these methods covers that?
Ha! Got me 🙂 None, I was just referring to analogue, but Digital would of course avoid these issues, like the Lyngdorf approach, as it’s not hitting on the analogue signal.
  1. Whether the Para 6 is better largely depends on the connected equipment. It may track better, but that's only a small part of the perceived sound.
  2. 'Better sounding resistors'? In whose estimation and in what context? Higher precision will improve tracking. SMD reduces inductance. Metal film has negative while Carbon film has positive temperature coefficient. How will those changes react with the associated equipment?
  3. Transformer taps change impedance which may affect sonics due to LCR filter values.
  4. Varying PSU voltage introduces its own artifacts
  5. Digital audio math becomes progressively worse as signal level drops and attenuation increases.
There is no free lunch.
The 128 step relay switched volume control in my Schiit Freya is great, it preserves an accurate channel balance, and you're never stuck in the "one click more too much, one less not enough" zone. The pleasant clicking sound it makes reminds you that it's there.
So seems like if soundstage and imaging remain solid at various volumes (and no noticeable noise when adjusting), the volume control is doing its job well.

The biggest problem with conventional potentiometers I have observed over the year is that they accumulate deposits over time that require cleaning to continue to work well.  The easy fix is to just exercise the knob periodically with power off to help remove deposits but eventually cleaning is required.

Can’t speak to the reliability of other types other than to say the technology used in marquee gear these days seems to have tackled the problem pretty well in general. Have not had issues with volume controls in quite a while (knock on wood...).
The biggest problem with conventional potentiometers I have observed over the year is that they accumulate deposits over time that require cleaning to continue to work well. The easy fix is to just exercise the knob periodically with power off to help remove deposits but eventually cleaning is required.
It really depends on pot technology and circuit topology. Some circuits are pot eaters. Same pot in another circuit will last a lifetime and longer.

The incorrect cleaner can destroy a pot faster than you can say Jack Robinson.


wolf_garcia
The 128 step relay switched volume control in my Schiit Freya is great, it preserves an accurate channel balance, and you’re never stuck in the "one click more too much, one less not enough" zone. The pleasant clicking sound it makes reminds you that it’s there.

Hey Wolf, you can get the whole thing 256 step passive in bal or se from this guy.
And if you search eBay you can just get the kit form without chassis as well.

https://www.ebay.com.au/itm/Finished-Relay-Volume-controller-Balanced-Potentiometer-Balanced-preamp/...

https://www.ebay.com.au/itm/Balanced-remote-volume-controller-RCA-XLR-Motor-potentiometer-preamp-C7-...

He's got it all, a real player.
https://www.ebay.com.au/sch/m.html?_odkw=Passive+preamp&_ssn=along1986090&_osacat=0&_fro...

Cheers George
The Lightspeed Attenuator, made by George, was probably the best volume control I have had in my system.  It was also the longest on going thread back in the day.  Im not sure why it isn’t still talked about and used by some of you.

The belles aria integrated also uses a burr brown volume control.  In essence, isn’t the volume control the only job of the preamp?  
The Lightspeed Attenuator, made by George, was probably the best volume control I have had in my system.
Thanks for the rap.

 
Im not sure why it isn’t still talked about and used by some of you
Haven't sent one out of Australia since the start of Covid Feb, we shut down with the "Covid thing" very early with imported/exports parts to make them with, and with the export of the final product.
I still won't send one OS as the last one took 4mts to get to the new owner in the US, he was happy in the end but quite upset during the delay.

Cheers George     
NP George.  Still to this day I think your pre’s are the best sounding pre for that kind of $ and I love the idea of no bs straight signal idea.  It worked very well with my Classe CA150, my Classe CA250 and parasound z dac.  
The Lightspeed just got out of the way and I had no issues what so ever with dynamics or lack of meat on the bones, per se.  


I'd like to offer a different take on the volume mechanism. I am a huge fan of Ayre Acoustics. They have developed the VTG - Variable Gain Transdonductance Volume Control for their preamps. No resistors in the signal path. Silver to silver self cleaning contacts. Very high tech. I do own the Ayre C-X7eMP and the K-5xeMP and love them! However I have a local Ayre dealer in Cincinnati, OH. and have listened to much of Ayre's equipment over the years. 

Ayre has begun doing zoom videos with three their top technicians where they have a cold beer and discuss different aspects of their gear. I've attached a link to the newest on their top line volume controls. 

https://youtu.be/HR414rhDmQM

N

No resistors in the signal path.


Must have something? Unless it uses the constant (high) "output resistance" of the stage before the volume as part of a divider to get shunted to ground.

Cheers George
Reading an Ayre VGT circuit description here
https://www.soundstageultra.com/index.php/equipment-menu/90-ayre-acoustics-kx-r-preamplifier-and-mx-r-mono-amplifiers in the paragraph that begins "First, in a traditional preamplifier, " it sounds like they have an input buffer before a gain stage that follows the level control. YAWN.

If you can’t dazzle them with brilliance, baffle them with bullsh!t.
I can't answer ..look at the potentiometer Steve McCormick designed for his statement preamplifier.
Then there is the system employed in 'The Truth' where there are no capacitors, resistors nor potentiometer in the signal path except for the photocell. I have built line-stages using the very good DACT pot and Guido Tent's switched relay system which is also very good with accurate channel tracking etc. but The Truth reveals the two systems mentioned to colour the sound. It is simply the cleanest way to control volume that I have heard. The improvement over the DACT is much greater than the DACT is over other pots like Noble or Alps

The much lower noise floor produces detail I did not know was there. Of course everything else is improved. Imaging, bass weight, huge dynamics and overall clarity and purity of notes. Terence Blanchard's trumpet is now awesome.
Photocells are semiconductors & thermally sensitive.

It is very difficult to ascribe sonic purity to a particular attenuation method as the surrounding circuitry and packaging all affect the sound.
@ieales, you state: Photocells are semiconductors & thermally sensitive. So what exactly are you saying? You saying I don't or shouldn't prefer the photocell system?

In all your above posts you have criticised whatever has been mentioned, so please tell us what perfect attenuation you use.


In all your above posts you have criticised whatever has been mentioned, so please tell us what perfect attenuation you use.
There is no perfect attenuation.

I use a self designed and built for my gear discrete matched 1% resistor silver contact stepped 0 to -22dB attenuator. Maximum 1dB step error is 0.05dB. L/R tracking is nearly perfect.
http://ielogical.com/assets/Audio/PassiveLC1.png & http://ielogical.com/assets/Audio/LC1.png

It may suck everywhere but here.

All pieces affect and are affected by to what they are connected.

There is no free lunch.

For me, the real improvement in the volume control in the Hint 6 (and the companion P6 preamp) is the numeric readout in the display. I can't stand preamps or integrateds with no readout, those which use a little light dot on the dial to indicate volume.