Stax SRM-T1W as my Soldering 101 project

[s1rrah]

I recently bought a Stax SRM-T1W and in speaking with others online, have heard that the PSU caps might be "dried up" and it's recommended that they be changed by default.

 

Reportedly, the unit sounds/functions fine and is in "like new" shape cosmetically, but I'd like to do the most basic of these changes if I end up keeping the unit as a nearly two decade old bit of electronics is still a nearly two decades old bit of electronics, no matter how it might look. So I'm considering this project my (re)introduction to Stax and so am intrigued/excited about working through a few minor mods, mostly in regards to extending longevity.

 

Can anyone here recommend the PSU caps that might need to be swapped and especially the specs regarding the sourcing of new ones to install?

 

I have no soldering experience but plan on using this item as my introduction to such. I figure with the size of the components, it might be just the sort of Soldering 101 project to get started with. ;-)

 

I have no desire to do any tube modifications yet (switching to ECC99, etc.) and really just want to immediately handle any internals that could be easily (relatively speaking of course) swapped.

 

I'll be receiving the amp early next week. 

 

thanks in advance for any assist...

 

.joel

[nikongod]

thanks in advance for any assist...

 

.joel

 

You are welcome in advance for saving you so much trouble, and possibly your life. 

 

Don't fucking touch this thing. 

I'm not saying that the piece of shit built 50 years ago is good and will work properly for another 50 years, it probably isn't good, and it probably wont work that long. I'm saying that this is the worlds worst first project. 

[shellylh]

By the way, I can vouch for Joel - he's been a friend of mine (originally from HF) for many years.  

 

Joel, listen to Ari, he knows what he is talking about.  Also, don't do/say anything too stupid here - a warning.     Also, when you joined there may not have been a welcome message, so I might as well tell you to read this in case you haven't already.

 

Edited November 15, 2013 by shellylh

[s1rrah]

You are welcome in advance for saving you so much trouble, and possibly your life.

Don't fucking touch this project.

That's precisely the information I was looking for.

Danke mate; I'll certainly be heeding that advice then.

(BTW.. Hey Shelly ... is it safe to borrow some cans yet?)

;-)

[shellylh]

Haven't seen any bb around lately and have been sprayed twice so probably but you probably should wait a few more weeks to be sure.  

[kevin gilmore]

andy built a diyT2 as his first electronics project ever.

(although he seems to have divine help on this stuff)

 

Getting the old caps out is not as easy as you might think, the circuit

boards are crap and if you don't already know how to solder, best

to have someone else do it and watch.

 

And yes the voltages in the thing (+ and - 350V) and the energy

stored in those caps is not something to take lightly.

[spritzer]

As Kevin said, while this may look easy enough the parts are a pain to work with.  The traces lift off the PCB if you just look at them the wrong way and to make matters worse, the PSU caps aren't proper snap in units but have longer leads.  These are bent into place and then flooded in solder so they can be a pain to replace with modern units. 

[s1rrah]

Thanks for all that.

 

As a complete electronics feckin idiot, I can't help but feel a sense of relief that I posted here; now my chances of death by electrocution are vastly diminished (while my chances of actually pulling off a first-time soldering project have increased). All day today I kept thinking, "Wow ... this is just like if somebody went surfing with me for the first time, on a particularly huge and nasty day and asked if they should put the leash around their neck instead of their trailing foot!" ... death or no death? Success or failure? Funny.

 

Anyway. I'm really wanting to settle on a general purpose electrostatic set up, something that lasts and is pretty good with just about everything I listen too (which is everything except rap) ... and so I think I'll enjoy the SRM-T1W gear for a few weeks and then put it back up for sell in favor of a significantly greater investment in a new Stax driver unit (some folk have recommended the 323S or the 727II) or one of the other DIY/3rd party builds.

 

For sure I'll be reading more before buying.

 

Shit man ... I just had a dude tell me that there is a whole calibration process to follow whenever one simply wants to swap the tubes in a Stax amp (if that is actually true) ... and his description included process notes that made my  head spin and included gear that I've never even set hands too.

 

So anyway ... 

 

;-)

[s1rrah]

Haven't seen any bb around lately and have been sprayed twice so probably but you probably should wait a few more weeks to be sure.  

 

Funny. I might not have a dynamic set up by then (major paradigm shi(f)t set in last week and suddenly I want to stop juggling dynamic cans and just settle on one really good electrostatic set-up. I have great fear about this. LMFAO ... I'll give you a shout in the next couple weeks then ... 

[shellylh]

Electrostatics are really good.  What headphones are you going to be using?

[s1rrah]

I'll keep the NIB SR-307's that come with the deal ... the amp? Undecided ... 

[The Expanding Man]

I have a t-1 that needs new caps and new tubes on my pile of DIY projects.

 

If / when I ever get round to doing it, I can share my experiences with you.  

 

Soldering takes a lot of practice.  I suggest you go to your nearest electronics/hobby store and buy some cheap kits with components and pcbs and practice soldering & desoldering on these.

 

The t-1 will pack some very high voltages and the power caps may contain some charge.  You need to be confident and have some level of knowledge and experience before tackling this project.

[s1rrah]

Electrostatics are really good.  What headphones are you going to be using?

 

For the time being, I'll keep the SR-307's that came with my latest impulse purchase (you know, the one that includes a SRM-T1W amplifier?) ... for the long term, once I get the aforementioned amp? Who knows? 

 

[spritzer]

The amps do need to be adjusted when swapping tubes but it's pretty easy to do.  The adjustment pots are pretty much the hardest part as they are touchy and can break apart.  On the last T1 I bought back to life both the offset pots split in two when I tried to adjust them. 

[s1rrah]

The amps do need to be adjusted when swapping tubes but it's pretty easy to do.  The adjustment pots are pretty much the hardest part as they are touchy and can break apart.  On the last T1 I bought back to life both the offset pots split in two when I tried to adjust them. 

 

Thanks mate.

 

Now I know my over-the-night crush wasn't really stupid, after all. 

 

;-)

[s1rrah]

I'm saying that this is the worlds worst first project. 

 

succinct. 

[s1rrah]

I'm really bugged by not knowing anything about soldering.

 

I've actually been looking for night time classes at the local community college. Seriously.

 

I've been in to the computer overclocking scene for decades (all the way back to the celeron days) ... and most of the really good hacks involve some sort of hard volt mods. In the past, I've had to "fake" it with soldering pencils and the like, conductive ink, etc. ... while my friends just broke out the proper soldering gear. It's like always having to swim in the kiddie pool. 

 

Anyway ... will most likely follow that advice (re: practice kits) ... though I have about 50lbs of old computer PCB's in my closet which will most likely be more affordable to mess with/practice upon. ;-)

 

 

 

 

Soldering takes a lot of practice.  I suggest you go to your nearest electronics/hobby store and buy some cheap kits with components and pcbs and practice soldering & desoldering on these.

[kevin gilmore]

if you can unsolder the power supply electrolytics from those 5 or more layer

computer boards, and the caps still have 2 wires sticking out of them, then you

are ready to work on stax.

[s1rrah]

I'll just stay in the kiddie pool for now. ) ... it's warm here and safe. LOL ... 

[Dusty Chalk]

I miss Heathkit.

[shellylh]

I think the SRM-323s should be good with any of the Lambdas like the 307 (I've never heard it though). I've thought of getting one for the office at times. It would probably have trouble with something like the SR-007.

Edited November 17, 2013 by shellylh

[Emooze]

I'm with mostly everyone on this. Reworking a board is so completely different from putting one together. If you don't have experience and the right tools, might as well just forget it. Even with a more robust board, it still takes learning.

 

It is nice to see someone with lofty DIY goals though. Keep at it and it'll be your project to work towards.