The Headcase Stax thread

[spritzer]

Cool, thanks. Is this potentially a higher quality solution than using transformers (building your own) with a SET amp?

I'm guessing it'll basically be a capacitor quality vs. transformer quality fight? Any thoughts?

An OTL amp will always sound better then running through one or even two transformers and for most amps you can use something like the Mundorf Silver-Oil caps with their 900vAC rating and they are very good caps indeed. I've always been meaning to buy some Chinese kit amp and fit it with a Stax output and some other features. I have one in mind but time is always a problem and so this remains untested in the long term. A simple switch on the front panel that would disconnect both legs of the output transformers while the Stax socket is active should create a good all rounder as you would have a p-p DHT SET for some speaker use.

[Nanoha]

An OTL amp will always sound better then running through one or even two transformers and for most amps you can use something like the Mundorf Silver-Oil caps with their 900vAC rating and they are very good caps indeed. I've always been meaning to buy some Chinese kit amp and fit it with a Stax output and some other features. I have one in mind but time is always a problem and so this remains untested in the long term. A simple switch on the front panel that would disconnect both legs of the output transformers while the Stax socket is active should create a good all rounder as you would have a p-p DHT SET for some speaker use.

Hmm, let's see if I can get this straight. How is it going to be both push-pull and single ended? \

[spritzer]

Hmm, let's see if I can get this straight. How is it going to be both push-pull and single ended? \

The SET wasn't supposed to be there. My bad! The input stage is single ended and all triode but it could use some work.

[Nanoha]

The SET wasn't supposed to be there. My bad! The input stage is single ended and all triode but it could use some work.

So this is an amp with DHT SET input and push-pull output? (And then the caps and resistors attach to the push-pull output?)

[drp]

A little Stax stack

I just got the final pieces of my little office rig, and since it's electrostatic, I thought I'd post it here. The stack up is a Sony D25 PCDP on top of a Stax SRM 252 amp, driving a pair of Stax SR-003 earphones. This entire rig fits in a 5.25 x5.25 x 2.5 inch space so will take up little space on my cluttered desk.

The D25 has the Turbo mod I started several years ago. Through the kindness of a new member of the other site, I was able to snag an image of the PCB, the spec on the DAC, and a bit of coaxing and coaching to complete the modification by rewiring certain pins on both DACs. This is another story, maybe for the DIY section if anyone here cares, but the outcome was a true dual DAC player (separate DAC per channel) that sounds incredible for a little portable. Although, no longer really a portable because the battery tray is now stuffed with Black Gate PS and headphone caps.

The 252 is just a few hours old but is already painting a fairly nice soundscape with the little earbuds. I just switched over to the HE60s; sounds like a "full size" rig. At first blush, it seems to have more detail than the SRD-7 Pro. Headroom is more difficult to ascertain due to the low voltage output of the D25. I'll have some fun experiments to perform over the holiday.

This little setup is also performing well at all volume levels; even at low volumes, which will make for some good background noise at the office. Plus, I type faster and more accurately when listening to headphones. Anyone got an explanation for this?

My next thought is to build/buy a small dedicated power supply, or perhaps a battery pack in a thin square box about the same dimensions as the amp itself. That would be slick and a certain sonic improvement over my crappy AC.

Back to spinning CDs. Currently digging Radio Head OK Computer.

[pabbi1]

This post is USELESS without pics...

[Nanoha]

I just got the final pieces of my little office rig, and since it's electrostatic, I thought I'd post it here.

drp, congrats on the nice little office rig!

[drp]

This post is USELESS without pics...

You've obviously never experienced my crappy photography. Here are a few funky lighting marvels. . . My mod pics are no better I'm afraid.

[Nanoha]

drp, is that the HE60 reterminated by Alex?

[drp]

drp, is that the HE60 reterminated by Alex?

You bet! Editing to clarify that the plug in my pix is the one to the SR-003. I think Pabbi1's KGBH pic has a good shot of the Stax retermination plug. It's very well done.

Alex also provided dust removal services. Mine now live in a plastic cover like Aunt Bessie's parlor couch, exposed only when music is playing.

I was at one point going to use the HEV70 pigtail that came with the retermintation to drive my SR-003s at the office, but this rig is more compact and I'm sure sounds better.

[Nanoha]

You bet! Editing to clarify that the plug in my pix is the one to the SR-003. I think Pabbi1's KGBH pic has a good shot of the Stax retermination plug. It's very well done.

Alex also provided dust removal services. Mine now live in a plastic cover like Aunt Bessie's parlor couch, exposed only when music is playing.

I was at one point going to use the HEV70 pigtail that came with the retermintation to drive my SR-003s at the office, but this rig is more compact and I'm sure sounds better.

Ah ha, I see; very cool.

The office rig looks really nice too. I love the dimensions.

[spritzer]

Ahhh, so you've received it. Congrats! These small Stax amps are perfect for office rigs.

[pabbi1]

SRM 252 added to the Christmas list - with the Azur 840c.... damn it, damn it, damn it...

[mirumu]

The 252 is just a few hours old but is already painting a fairly nice soundscape with the little earbuds. I just switched over to the HE60s; sounds like a "full size" rig. At first blush, it seems to have more detail than the SRD-7 Pro. Headroom is more difficult to ascertain due to the low voltage output of the D25. I'll have some fun experiments to perform over the holiday.

I'm pretty sure the SRM-252 is more detailed than the SRD-7 Mk2 I own as well, it just doesn't provide the same output power. The 252 is a very nice piece of kit for the money. It even drives the SR-404s surprisingly well.

[Cosmopragma]

The Mk2's are highly sought after and can go for way more then 200$.

I've sniped a SRD 7SB Mk II this evening.

I've wanted a spare SRD for modding purposes (just in case I wreck one in a modding attempt), and here it is.

Wasn't exactly cheap though.

Indeed more than $200.

Feck, the SRD 7 Pro I've purchased less than a year ago did cost less than $100.

[Duggeh]

Stax prices on ebay have soared in the last 12/24 months. I sold an SR-3N I bought for ?15 for more than ?100. I wouldn't have paid that for it myself, but I was happy to take the money. That was in January.

[Cosmopragma]

I'm pretty sure the SRM-252 is more detailed than the SRD-7 Mk2 I own as well,

My SRM-313 (from what I've heard similar to the SRM-252 but with a built-in power supply) isn't more detailed than my slightly modded SRD7Pro/CEC Amp 3300 and overall I prefer vastly the SRD/speaker amp combo.

May I ask what speaker amp you are utilizing?

[mirumu]

My SRM-313 (from what I've heard similar to the SRM-252 but with a built-in power supply) isn't more detailed than my slightly modded SRD7Pro/CEC Amp 3300 and overall I prefer vastly the SRD/speaker amp combo.

May I ask what speaker amp you are utilizing?

My amp is nothing fancy, some local brand, Digitech, although I don't recall the model (I'm not currently at home to check). You're no doubt correct in suggesting that might be a factor but the SRD-7 Mk2 is definitely adding some grain of it's own that I can't detect from the amp on it's own. Hopefully soon I'll be able to confirm once my DIY transformer box is complete. I'm not sure how similar the SRM-252 and SRM-313 actually are though, their circuit boards certainly looked rather different. I had thought there wasn't much in common between the two although I may very well be mistaken.

[Nanoha]

Perhaps I should have kept the SRM-Xh. Now that I think about it, it would have been great for transportable use.

[ojnihs]

Perhaps I should have kept the SRM-Xh. Now that I think about it, it would have been great for transportable use.

nah, just get a wooamp and figure out a way to use it portable...

[spritzer]

My amp is nothing fancy, some local brand, Digitech, although I don't recall the model (I'm not currently at home to check). You're no doubt correct in suggesting that might be a factor but the SRD-7 Mk2 is definitely adding some grain of it's own that I can't detect from the amp on it's own. Hopefully soon I'll be able to confirm once my DIY transformer box is complete. I'm not sure how similar the SRM-252 and SRM-313 actually are though, their circuit boards certainly looked rather different. I had thought there wasn't much in common between the two although I may very well be mistaken.

The SRD-7 has it's own colorations but they have many positive traits over the cheaper amps, namely dynamics and they are much smoother. Plug in the BH and the transformers become a distant memory...

The 313 and 252 share some of the circuit but the PSU in the 313 is of course much bigger with higher voltage swing.

Perhaps I should have kept the SRM-Xh. Now that I think about it, it would have been great for transportable use.

The new amps are much, much better and can be had for 150$ or less from Japan. They are almost always in the combos but selling a SR-202 wouldn't be too hard.

[mirumu]

The SRD-7 has it's own colorations but they have many positive traits over the cheaper amps, namely dynamics and they are much smoother. Plug in the BH and the transformers become a distant memory...

Yes, the 252 and SRD-7 Mk2 are good in different ways. My aim is definitely to build a system that is less of a compromise. Costs have been ensuring that I will not be there any time soon unfortunately.

The 313 and 252 share some of the circuit but the PSU in the 313 is of course much bigger with higher voltage swing.

Oh, okay. So they're more similar than I realised.

Perhaps I should have kept the SRM-Xh. Now that I think about it, it would have been great for transportable use.

I saw one going on a certain auction site earlier. The 230V Bias is what puts me off.

[spritzer]

Yes, the 252 and SRD-7 Mk2 are good in different ways. My aim is definitely to build a system that is less of a compromise. Costs have been ensuring that I will not be there any time soon unfortunately.

I'm also looking into some form of Stax amplification that is less compromised then the Stax amps at a similar price.

I saw one going on a certain auction site earlier. The 230V Bias is what puts me off.

THe SRM-Xh is Pro only though there is a normal solder tag on the PCB but I didn't test it. Stock it was available without a bias supply and Pro only as a part of the Spirit system. The one without a bias supply was marked as "Electret Energizer" or something like that.

[scottiebabie]

1st post in your esteem forum and based on all i've been reading, i like it! seems like no BS hypocrites showoffs are welcome or they get their comeupperance ! hope u guys take it easy on a noob like me though.

that said, im seriously thinking of getting a taste of this here stax electro-cutes cans after reading all the joyous reports. due to my very tiny budget, which system would be best? 1. 3050a sig system or 2. 4040 II sig system? theres 400 reasons why i should go for the cheaper rig but hell...if the diff is real and big enuff, mites well go for broke. am thinking of gettin it from Bluetin btw.

O and i read the 6moon comparo which says that the 30s are the better deal and dont lose out much sonically. what says u stax sages?

[spritzer]

First off, 6moons is a horrible source for anything but pretty pictures though there is one or two reviewers with some sense.

When it comes to Stax there is a wealth of choice and you can either have the new models, pick up a vintage system or mix the two. The 4040 is a clear step up from the 3050 but I've never liked the 006t amps as much as I like their older brothers, the T1, T1S and T1W. The 313/323 are good amps but they can be a bit cold in the wrong system but we are talking about 500$ amps here so they can have faults. Another option would be to pick up a used SRM-1 Mk2 Pro amp, preferable with a "C" serial number above 5000 and use it with either the 303 or 404 earspeakers. The older amp is very different from the 313/323 and IMO sounds quite a bit better and it has more power. It runs pretty hot so that might be an issue but the tube amps do that as well.

On the phones side then the SR-303 is the sweet spot of the range. The 404 is more refined and better but the difference is hardly worth 100$. On the used market you can find any one of the previous models but prices are very high right now, even higher then what the new models cost so unless you stumble across some local deal it's hard to find any of the Lambdas/Gammas/Sigmas at a reasonable price.

I would personally get a used amp and new phones and spend the rest on other aspects of the system. Better IC's and PC's help quite a bit and you could also do some mods to the amp and upgrade it's internal wiring and connectors.