[thathertz]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif I have the exact same transformer on my MPX3 as thahertz does. So assuming in was wired for correct use, and not the incorrect way the Extremes seem to have been wired, since mine is not a "12V" model - no voltage switch, etc. -- it would seem to have enough current delivery to handle it's application: 272BX 95VA, sec. 300-0-300, DC ma 100, Fil.#1(rct) 5.0v @ 2a, Fil.#2(htr) 6.3v @ 3.0a. 3 amp delivery at 6.3V for heater current - even using 3 ECC32's which draw .9a, this would seem to be in spec. Am I reading this correctly? I realize this doesn't mean my MPX3 might not have other issues...

Skylab, just to clarify my post above. The image of the 272BX I posted
was taken from the web site (link also above) and was just used to
confirm identification of the type of transformer. I don't know if that
IS my exact model no. since the label has been removed presumably
by Mikhail.

 

[mrarroyo]

Quote:

Originally Posted by moredes /img/forum/go_quote.gif My MPX3's transformer is warm, but definitely not what I'd call "hot", after playing for several hours. I can keep the back of my hand on the cover as long as I like. (the back of the hand is much more sensitive to temerature than the palm-side) Mine is 110V. Thank you, Kevin, for explaining the discharge stick!

My transformer cover behaves the same way, and it has the Supra transformer. Thank you all!

 

[thathertz]

Hmmm...my transformer is 110v.

I'm using a step down converter which I've just looked at and it
states 50Hz (for the UK). It looks like it will also output 50Hz and
not 60Hz.

The cause of MY overheating transformer?

Quote:

Because the electrical current is dependent of the Voltage and the Hertz you cannot connect electrical equipment with a motor and or transformer in it, to a Voltage other then stated on the nameplate. If you connect 60 Hertz equipment to a 50 Hertz mains the internal current goes up with 17% and can cause a burn-out. If you connect 120 Volt equipment to 220 Volt the current goes up with 100% and surely causes a fast burn-out. This means even if the Voltage is the same, or if you put a transformer in between to transform the Voltage, you still cannot connect a 60 Hertz motor or equipment with an internal input transformer to a 50 Hertz mains.

http://www.kropla.com/frequency.htm

 

[Tyson]

Quote:

Originally Posted by thathertz /img/forum/go_quote.gif Hmmm...my transformer is 110v. I'm using a step down converter which I've just looked at and it states 50Hz (for the UK). It looks like it will also output 50Hz and not 60Hz. The cause of MY overheating transformer? http://www.kropla.com/frequency.htm

Dude, this thread is NOT going to reassure you that your amp is really OK (which seems to be what you are after). The ONLY way to make sure your amp is OK is to take it to a competent technician and get it checked out. You have more than enough information to provide him so that he can do a good job.

 

[kevin gilmore]

This is my discharge stick for really big stuff like xray tubes.
Certainly works on the smaller stuff too.

http://gilmore.chem.northwestern.edu/discharge.jpg

 

[thathertz]

Quote:

Originally Posted by Tyson /img/forum/go_quote.gif Dude, this thread is NOT going to reassure you that your amp is really OK (which seems to be what you are after). The ONLY way to make sure your amp is OK is to take it to a competent technician and get it checked out. You have more than enough information to provide him so that he can do a good job.

Thanks, I'll decide when I have enough information.

 

[Tyson]

Quote:

Originally Posted by thathertz /img/forum/go_quote.gif Thanks, I'll decide when I have enough information.

Just curious, what "exactly" would be required for you to actually take your amp to someone for a simple checkup?

 

[thathertz]

Quote:

Originally Posted by Tyson /img/forum/go_quote.gif Just curious, what "exactly" would be required for you to actually take your amp to someone for a simple checkup?

Tyson, give it a rest. If you have an issue with me then send
a PM and I'll reply later this evening.

 

[Tyson]

I apologize if I've come off a bit adversarial here, it's not an attack on you. I'm actually very concerned for people's safety (which is why I started the thread). I know these amps are unsafe. The reports you are starting to see on head-fi are just the tip of the iceberg. I'm not saying the amps sound bad, and I'm not saying that it was dumb to buy the amp (hell, I bought one). But, based on everything I've seen here (and in off-line communciations), these amps have safety issues. Please, please, please have someone look at it, it's easy and inexpensive to do that, and it will keep you (and your headphones) safe.

I must be getting old, I'm starting to sound like my parents

I'll stop bugging you about it now, you're big boy, you can make your own decisions.

 

[thathertz]

Quote:

Originally Posted by Tyson /img/forum/go_quote.gif I apologize if I've come off a bit adversarial here, it's not an attack on you. I'm actually very concerned for people's safety (which is why I started the thread). I know these amps are unsafe. The reports you are starting to see on head-fi are just the tip of the iceberg. I'm not saying the amps sound bad, and I'm not saying that it was dumb to buy the amp (hell, I bought one). But, based on everything I've seen here (and in off-line communciations), these amps have safety issues. Please, please, please have someone look at it, it's easy and inexpensive to do that, and it will keep you (and your headphones) safe. I must be getting old, I'm starting to sound like my parents I'll stop bugging you about it now, you're big boy, you can make your own decisions.

No problem Tyson

I'm sorry for the tone of my responses.
It's Sunday, sunny outside, and I'm in here doing my accounts

I appreciate you concerns and I'm looking for suitable techs in the
UK now. I probably asked more questions than perhaps seemed
necessary but I'm new to tube amps and I'm not good with
electrical tech! I fully intend to get my amp checked out.

Thanks for the warning.

 

[agreenspan]

Hi all, I've really enjoyed reading this thread. I purchased an extreme with upgrades last year - just moved and receipt with details is still packed . It has a big transformer in a square shaped housing that is mounted parallel to the chassis (not like a diamond when looking down at the top). I've never had any problems with it, and enjoy it very much, but I would appreciate any advice any of you could give. I live on Nantucket Island, and there is no "tube guy" here that could check this; I will mail it off to a tech to check it for me. I've opened the chassis and attached pics.
Thanks,
Stephen.

 

[penger]

Well that's the newest PCB version I've seen to date. The one I had was from '07 and I've seen ones from '06 and earlier, but that's interesting to see.

 

[PhilS]

Quote:

Originally Posted by thathertz /img/forum/go_quote.gif Thanks, I'll decide when I have enough information.

thathertz, there was also a lengthy thread in 2004, which expresses many of the same concerns set forth in this thread regarding safety issues relating to SP amps, including the potential shock hazard. Indeed, I seem to recall that several predicted back in 2004 that SP amp owners were in danger and that one or more SP amp owners would likely receive serious electrical shocks within the near future.

Anyway, I point this out as you might want to check out that thread for additional issues and discussion in your search for information (it was the one eventually closed by jude in October 2004, so he has the last post). It also gives you some background on the issues, and demonstrates that this issue (or certain aspects of it ) has existed for a long time, which cuts a lot of different ways, I guess.

Disclaimer: Nothing said herein is intended to imply that SP amps are not a safety hazard or that anybody should or should not take certain action with respect to their particular amp.

 

[Skylab]

Well, I ran a little test today. I turned on my MPX3 and my Decware CSP-2 at about the same time, to compare the transformer temperature. The CSP-2 has a much larger transformer than the MPX3 does, but it uses a tube rectifier. It also uses 6 6DJ8's, which draw about half what a 6SN7 does in terms of heater current. But that's the point, isn't it? The CSP-2 uses a transformer that can handle the current demand that the tubes present.

Anyway, the CSP-2's transformer never gets anything more than slightly warm. After 1 hour, the trafo on the MPX3 is so hot that I can't touch it for more than 3-4 seconds.

So the MPX3 is staying on the shelf, and the CSP-2 has become and will remain my main headphone amp. I know Steve Deckert from Decware knows what he's doing, and is honest. I always knew this was important - never realized just HOW important.

 

[spritzer]

Ahhh the "Amp wars", such fond memories of idiotic fanboys beating up other idiotic fanboys while accomplishing nothing and thus not stopping the incompetent "designers" which we are stuck with today.