The Headcase Stax thread

[faust3d]

Yeah, transmission line desktop speakers

[spritzer]

That could be done... When I'm "done" with this amp phase I'll build some transducers just for kicks. How about wire stators for an ESP?

[Duggeh]

You could build your own set of Peters Balls

[mypasswordis]

What if I made my own sealing pads around the insides of the Float frame, Lambda-style?

I need to find a better way for the drivers to be coupled to the frame than just thin foam, and maybe seal/damp some stuff. Yet more modding to be done... why can't I just buy a headphone that was made right in the first place

Edit: I just got zapped. Whoops.

[Duggeh]

I tried that pads inside solution with Ergos and Floats, it's unworkable.

[mypasswordis]

Do you mean unworkable from a technical standpoint or that it sounds hideous? I don't see how it would be unworkable, the back padding would have to be thicker than the front to match the head, and wrap some leather over it, stick it to the frame with double-sided tape.

[Duggeh]

Its unworkable in that there isn't space inside the chassis to create the baffle and pads.

[mypasswordis]

Oh, when I meant inside, I just meant... around the ears. I'm going to try and make pads that come in from the back and go up almost to the front, leaving a small gap so that they don't completely seal.

There shouldn't be too much to do on the inside but damp the frame a bit and couple the drivers to the frame better.

The sound is growing on me. It's just very slightly bright (lower treble peak, methinks) and a bit flabby on the bottom and doesn't extend far enough into the bass, which is just due to the nature of the headphone and not the drivers themselves.

[HeadphoneAddict]

Aaaaah, oh no!

I was hoping that the KGBH will brighten up and increase treble aggressiveness a bit. Not too much, just a little bit would be enough. Then I could consider selling the HE90 and SR-Omega. And maybe request a member name change to Spritzer v2.

Compared to the Aristaeus, the ES-1 has increased dynamics and makes the O2's more energetic and less laid-back, with more treble energy and some more brightness overall.

This is already with some attempts at tube-rolling on both amps, for example, Sylvania 5751 instead of 12AX7 on the Aristaeus, and Tung-Sol 2C51, Sylvania 6SN7 metal base and Mullard EL34 instead of WE 396A, Ken-Rad 6SN7 and GE 6CA7 on the ES-1. This is probably useless info to most people, but I mention it because tube changes make some differences.

I got the impression that even Naaman was a little disappointed with the O2 on the KGBH, at least vs his K1000 out of the B22 (or the Jade - Gasp!). His is not a KGBHSE and it's possible the SE would be better, or rrolling tubes could change that completely as well. But the Buffalo DAC was great as a source and I wouldn't change that in his rig.

With the GES I was able to eek more treble out of the O2 Mk1 and Mk2 with a change from the stock 12BZ7 to some Telefunken smooth plate 12AX7 or GE "Wurlitzer" 12AX7. It gets even better when I switch from feeding the GES from the Apogee mini-DAC and use the Pico DAC/amp as a source/preamp.

Alas, I worked out a trade of my O2 Mk1 for a low SN K1000 and we should both be cross shipping on Monday. I'm keeping the O2 Mk2 though, along with the Jade, HE60, ESP950 and the others.

[Elephas]

I'm not really expecting the BHSE to be better than a regular BH, but I won't have both to compare, so that's a moot point.

I'll have the ES-1 and Aristaeus to compare with the BHSE. If the BHSE is close to the ES-1, I'll be satisfied. Some of you guys heard the ES-1 at the 2008 Colorado meet. I've been having fun tube-rolling and trying out combos with the adapters: 2C51, ECC1 (5751, 12AU7, 12AX7), 5687 and 3D21 as well as the 6SN7, 6BL7 and EL34 types. My favorite tubes are unfortunately mostly the rarer and more expensive ones.

Hopefully the BHSE will be responsive to various EL34. I've prepared a bunch of EL34 to try.

[spritzer]

You could build your own set of Peters Balls

Stacked stators are definitely on the to-do list.

I got the impression that even Naaman was a little disappointed with the O2 on the KGBH, at least vs his K1000 out of the B22 (or the Jade - Gasp!). His is not a KGBHSE and it's possible the SE would be better, or rrolling tubes could change that completely as well. But the Buffalo DAC was great as a source and I wouldn't change that in his rig.

Perhaps Naaman could chime in what the bias for the output stage is. Considering he's using similar heatsinks as Justin used in the older amps he must have scaled back the bias.

Hopefully the BHSE will be responsive to various EL34. I've prepared a bunch of EL34 to try.

The difference on my old unit was night and day. Even brilliant new production tubes like the SED lacked a whole lot compared to the Mulllards.

[moray james]

The RCA 7025 is to me the best 12AX I have listened to. The 7025 is an ultra low noise 12AX and it has dual heater coils which are wound in opposite directions to cancel heater supply noise amongst other physical differences. Sovtec build a copy of a 7025 not as good bu not bad either and very inexpensive. I still like the RCA 7025 best. I am with Birgir as far as EL34's go Mullards are very well balanced with excellent mids. You could also play with 6CA7.

6CA7 / EL34 Vacuum Tube List

12AX7 Vacuum Tube List

[spritzer]

The 6CA7's offer more bass (the bloated and messy type though) but the midrange is a mess. They work ok with the HE90 and are rumored to be better in the ES-1 since they can handle the abuse which the grounded heater dishes out.

[Elephas]

Yes, the GE 6CA7 works well in the ES-1 with the HE90, HE60, SR-Omega or 4070. They don't do as well with the O2's.

I have a pair of Tung-Sol 7025 labeled GAP-R Computor but no RCA.

I like using 5751 in place of 12AX7, and have had excellent results with 5751 in the Aristaeus. Very crisp and clean sound.

I've been able to try some 5751 in the ES-1 using the ECC1 adapters, and they work very well too. Right now, I'm using Sylvania 5751WA, Tung-Sol 6SN7 black glass round plates, and Mullard EL34 xf1 with the O2Mk1. Sound is very refined, extremely liquid and silky smooth. I think that few headphones can match this level of smoothness; not the HE90, SR-Omega or R10. Details, imaging, dynamics and tonality are very good. I think there is still a touch of darkness, but it is slight.

[HeadphoneAddict]

I'm not really expecting the BHSE to be better than a regular BH, but I won't have both to compare, so that's a moot point.

I'll have the ES-1 and Aristaeus to compare with the BHSE. If the BHSE is close to the ES-1, I'll be satisfied. Some of you guys heard the ES-1 at the 2008 Colorado meet. I've been having fun tube-rolling and trying out combos with the adapters: 2C51, ECC1 (5751, 12AU7, 12AX7), 5687 and 3D21 as well as the 6SN7, 6BL7 and EL34 types. My favorite tubes are unfortunately mostly the rarer and more expensive ones.

Hopefully the BHSE will be responsive to various EL34. I've prepared a bunch of EL34 to try.

The KGBH Naaman has reminded me more of your ES-1 with the O2 Mk1, with a little harder attack or more aggressive sound or punch to it. It wasn't bad, just different than what I am used to (a more tubey romantic sound). I think the right tubes would make a big difference in the sound, and it could always be different just from that.

[Elephas]

I was thinking of canceling my BHSE order. My ES-1 is working very well, and there are many tube combinations to try. With the BHSE, I would only be able to change the quad of EL34.

I realize this isn't really a shortcoming of the BHSE. Presumably it sounds good the way it is designed, as a hybrid. But I like rolling tubes and I've found that the preamp tubes affect the sound more in the ES-1, Aristaeus and also the Zana Deux's single 6SL7. I got a bit carried away acquiring tubes and have enough to last a long time.

But one can never have enough tubes!

I was saving the quad of Mullard EL34 xf1 (that I'm now using in the ES-1) for the BHSE. Also a quad of Philips metal base, an unmatched quad of TF, and some xf2's as well as Tesla, GE 6CA7, RFT dimple tops and a couple of other types. Recently I saw the new black glass Shuguang Treasure 6CA7-Z on sale and I plan to get a quad.

But even with all these choices, I'm not expecting changing the power tubes in the BHSE to change the sound as much as changing the preamp tubes in the other amps. The O2Mk1 and O2Mk2 are already sounding as good as I can imagine driven by the ES-1. I can't imagine them getting any better.

[deepak]

Keeping the other tubes the same in the ES-1 and just swapping out the quad of EL34s, how big is the difference between various EL34s?

[HeadphoneAddict]

The O2Mk1 and O2Mk2 are already sounding as good as I can imagine driven by the ES-1. I can't imagine them getting any better.

Isn't that something a newbie would say? You have to have a better imagination, Spritzer would say.

[spritzer]

The BH just gets out of the way and lets the phones do their thing. Not only from a fully DC-coupled neutrality standpoint but by supplying the phones with all the current they need, no matter the load. At first glance this appears to be a boost to the bass region and some extra treble but change the fit to make the bass a bit leaner and it all snaps into place. The BH will never be an amp to impress and it gives ruthlessly revealing a whole new meaning.

The ES-1 is a very limited from a design standpoint and no amount of bling caps and other crap like that will fix it. It is after all just a 1968 Stax design, a good one though but it lacks all the refinements that the last 40 years have brought us. Then you add the crap construction and the possible filament fiasco and amp will chew through those expensive tubes in no time. Before you commit to anything but new production tubes in the ES-1 I would have it checked out to see if the same filament wiring is feeding the entire amp. I've heard enough horror stories...

That said you might prefer the ES-1, hell you liked the Jade after all and the ability tube roll may be appealing to some. With the old BH I tried every EL34 I could get my hands on but after that the Mullard XF2's were the only ones I used and a single quad at that.

[Elephas]

I think it's safe to say I'm just not as discerning as some other people. Our disagreements about the amount of difference between the O2Mk1 and O2Mk2 showed this.

I tend to like anything I'm listening to at the time. It could even be a dynamic, such as a Grado RS-1 or AT W5000. I would be interested in seeing Spritzer's horrified expression while he's listening to either of those headphones.

Keeping the other tubes the same in the ES-1 and just swapping out the quad of EL34s, how big is the difference between various EL34s?

Hmm, this is not easy to describe.

Some types such as RFT dimple top and Tesla work OK, but they just aren't as smooth or refined as the Mullard xf1, xf2 and Philips metal base. The GE 6CA7 also seem less refined but they are punchier and more energetic, with more bass quantity but also muddier bass.

But the effects can be different depending on the headphones used, keeping everything else the same. For example, I think the 6CA7 is warmer and fuller-bodied, and more suited to the HE90 and HE60 and less suited for the O2's.

I think the saying about the last 5% comes into play. The Mullard xf1 I'm using now are great. I prefer them greatly over the 3D21 with adapters or the RFT dimple tops. After hearing the O2Mk1 with them, I can't stand to switch back. But the difference in cost? It's quite large, especially vs. the inexpensive 3D21.

Given a set budget and the choice, I would put more money towards the preamp tubes than the EL34. I could probably get by with a set of xf2. Yes, they would be sufficient.

All of the above is with the ES-1, of course.

Isn't that something a newbie would say? You have to have a better imagination, Spritzer would say.

I'm still a relative newbie! I've heard a lot of headphones but not that many amps. I've only attended one meet, a long time ago, and haven't pitted my gear head-to-head against others at a meet. I consider doing so to be a good reality check against self-delusion or self-stupidity.

[Dusty Chalk]

I think it's safe to say I'm just not as discerning as some other people. Our disagreements about the amount of difference between the O2Mk1 and O2Mk2 showed this.

I don't think of it as "less discerning", I think of it as "less exaggerating" (as in, the differences between the two). Some people want to glorify their own ability to hear, so that when there's a subtle difference, they say, "OMG, it's like night and day".

[aardvark baguette]

From my own experience, equipment differences are extremely subtle at the beginning, then over time become far more apparent. I've always assumed this was due to 'training the ear'.

[spritzer]

From my own experience, equipment differences are extremely subtle at the beginning, then over time become far more apparent. I've always assumed this was due to 'training the ear'.

That's my take on it as well but on top of that I'm just an anal bastard. The differences between the Mk1 and Mk2 SR-007 may be minor in absolute terms (both are brilliant transducers) but to my ears one is the best headphone ever made and the other is far from it.

[catscratch]

I think it's safe to say I'm just not as discerning as some other people. Our disagreements about the amount of difference between the O2Mk1 and O2Mk2 showed this.

I tend to like anything I'm listening to at the time. It could even be a dynamic, such as a Grado RS-1 or AT W5000.

Say rather that you're less perfectionistic and anal about your gear. Which I would like to be, but the reality is very far from that.

I simply *cannot* for the life of me enjoy a system that has obvious flaws. Every tiny little flaw drives me up the wall. That's why I like the O2 Mk1 so much - not because it's the most exciting, most vibrant, most energetic presentation there is, but because it does nothing wrong. There is very little in its sound that annoys me, assuming that the signal path is correct. Nearly every other headphone has flaws, some of which make them impossible to enjoy.

Now, this doesn't mean that I don't enjoy music on less than perfect systems. I can listen to my favorite stuff on my crappy Bose car system and like it. I can listen to laptop speakers and like the music. I've listened to music on nothing but the E500 over the last week since I'm never home, and I liked every minute of it, though admittedly the E500 isn't bad.

However, I can't like a system unless it's flawless.

Frustration with gear is what made me upgrade this far, and I'm not anywhere near done. There are still flaws to iron out.

I'm also not a headphone polygamist. There are certain headphone niches I want to fill - closed/computer/gaming/movie headphone, isolating portable headphone, primary critical listening headphone. But I don't need a different headphone for different genres and flavors. I just want one for each category, as long as it's perfect for its intended use.

(so why do I have the massive stash then... )

[Dusty Chalk]

Uh...you know there's no such thing as "flawless". There's better and worse, but there's absolutely no such thing as flawless. You might listen to a system and think it's flawless, and it's probably pretty good, but you'll hear flaws in it eventually, if you listen to enough different musicks on it.