[MacDEF]

First of all, thanks, Jan for the response!

Quote:

Originally posted by Jeff Guidry I find it strange how we are perfectly willing to SAVAGE other companies for design and sound flaws, minor and major, but when it comes to Headroom, we circle the wagons and have long, breezy running debates on why people who have a problem with their stuff SHOULDN'T have a problem with their stuff.

I think that's a bit of an overstatement. This is one particular design issue, and, as Joe brought up in the first place, some of the PortaCordas also have pot problems.

The fact is that inexpensive pots aren't perfect. Some Total Airheads have the "scratchy" issue, some don't. Some PortaCordas have balance issues on the pot, some don't. I've even seen comments about the pots on JMT's amps. You get what you pay for, and at this price range, you're not going to get perfection. I won't "savage" HeadRoom or Jan for these problem. It has nothing to do with it being HeadRoom. It could be my next door neighbor building an inexpensive amp.

Quote:

In my opinion, this is a by-product of Headroom's sponsorship of this forum. If negative comments about Headroom's products are not allowed, let's just come out and say it. And cut the ********.

Jeff, this is a ridiculous and, frankly, insulting statement (because it implies that those of us defending HeadRoom in this thread are somehow shills for the company). If you think criticism of HeadRoom's products are not allowed, I suggest you use the search feature and see what you come up with. Heck, even Kelly and I, who seem to be sympathetic towards HeadRoom in this thread, have made critical comments about various HeadRoom amps. There are PLENTY of negative comments about HeadRoom products in the forums. Some are debated, just like negative comments about EVERY other product are debated.

This is the old "if you can't out-talk them, question their motives" tact. Which is made even more distasteful by the fact that there is no "win" or "lose" here -- we're having a discussion in a forum.




Quote:

Originally posted by Joe Bloggs DIY it is then But really... Somebody tell me where Sony gets the pots for their pcdps.

Joe, remember that cheap pots aren't all bad. It's just that their quality is extremely variable. You could buy a box of them, and some would sound great, while some would suck, and the rest would be in between. Your Sony PCDP happened to get lucky. My old Sony PCDP didn't

Quote:

Originally posted by jpelg Since you never actually answered my question, I will assume that you have not actually heard the new Airheads.

While I owned the old version, I haven't heard the new one yet. I didn't answer your question before because I don't find it relevant to this particular discussion. All that is relevant for a logical discussion of this topic is verification of two facts: 1) that the new version has better sound than the old one; and 2) that at least some units of the new version have a bit of noise when you change the volume. Since people who have heard both the new version and the old version pretty much all say the sound quality of the new one is better, and since the people who built the thing spend time trying to make it sound better, I think it's a pretty good bet that the new one sounds better. Since at least a couple people who have heard the new one (including you) have experienced the pot noise, and HeadRoom has openly discussed it, it's safe to assume such noise exists. With those assumptions out of the way, we can logically discuss the merits of the design choices that Todd/Tyll/Danny explained

This entire discussion has been based on the assumption that there is a design tradeoff between better sound/scratchy volume change & worse sound/quiet volume change. If you want to have a debate about whether or not the sound-while-not-changing-the-volume of the new model actually is better than the old model, then I'll refrain from commenting, because then I would have no basis for doing so

 

[jarthel]

you get what you paid for. Better POTs are more expensive. I bought a $50 POT for my DIY amp but then again I could have bought a $2 one.

 

[Joe Bloggs]

Quote:

Originally posted by danny We do have a two pot option. It is called the BlockHead. For a slight fee, we will be more than happy to upgrade your Airhead to the BlockHead.

That is so sarcastic I don't even know what you really intend to say.

Do you or do you not offer modifications for adding a balance control in your lesser amps?

 

[danny]

I would have said wry, or tongue-in-cheek, myself.

At this time we do not offer a balance control in our 'lesser' amps.

 

[Joe Bloggs]

Do you manually adjust the volume on the two channels on the BlockHead? A ganged pot and a balance control would seem to be more convenient... but I suppose that messes up the sound more?

 

[tangent]

The Blockhead is a true dual mono amplifier -- two completely separate amplifiers, one for each channel. That's why it has a separate volume control for each channel, and why it requires special cabling.

 

[Joe Bloggs]

I thought a ganged pot is in effect two pots stuck together?

 

[tangent]

I see what you mean now, Joe. I suppose they could have done that, but remember, the Blockhead is about isolating each channel from each other as much as possible. If they'd used a dual ganged pot, the two channels would "meet" inside the pot.

And, then they'd have tracking error to contend with.

 

[kelly]

I'm not sure this is called a ganged pot, but don't dual mono amps sometimes join the pots mechanicallly (via a belt or chain) so that there literally are two pots but there's only one knob? I suppose you'd lose balance control that way, though.

 

[tangent]

Quote:

I'm not sure this is called a ganged pot, but don't dual mono amps sometimes join the pots mechanicallly (via a belt or chain)

...Chain gang?

 

[thomas]

The two channels of any pot are always completely independant, so they can be used in monoblocks without any problems... (unless the "0.0001 amp current going through the pot causes "resonance" along the shaft of the pot, causing a loss of
"airiness" and makes it sound like a "veil has been placed over the headphones"

Seperate pots are used to allow balance control as well, but if they're chained together then its just a marketing ploy. (audiophiles will only buy monoblocks if they can be sawed down the middle and still operate)

 

[Geek]

In response to what has been said insofar, I have the Beyer DT250 @ 80 ohm impedence headphones. These are highly efficient (almost as loud as the el-cheapo commercial headphones off of a raw CD player amp) and easily bring out lots of annoying background noises etc. (when run through my cheap old sound card I clearly hear some static, popping, etc).

I run them through a basic Airhead amp which I purchased about a month ago (new design, 4.5v). When moving the pot, I notice almost no noise until I reach EXTREMELY loud levels (1/4 to 1/3 of max volume level). Many people complain of pot noise but what little noise I can hear is insignificant.

Note that the Airhead series isn't really meant to be constantly tweaked volumewise. Read HeadRoom warnings about hearing loss and constantly fiddling w/volume, and take note of tough pot design.

Pot noise might be an issue with higher impedence headphones, but do take note that I own only the DT250-80.

I have run the Airhead through a regulated 500mw power supply all the way up to 12 volts (compared to the pot-noisy 9v model that some have qualms about) and find no perceptable change in pot noise.

I must side with the "better sound quality outweighs quieter pot" crowd as I have listened to the old TAH and personally believe the new regular AH sounds perceptably smoother and punchier. Weather this comes from simpler pot design or other component upgrades I do not know.

I hope my post made sense.

Cheers,
Geek

 

[Joe Bloggs]

So how about having a volume pot chain gang (

) plus a balance control knob?

Another question: do pots with stepped action have better tracking than continuous pots?