Toshiba Ouput Tranistors 2SD424 & 2SB554 (many Adcoms)

Systems

ben62670 wrote: »

IRF244, and IRF9240

What about them?They are IRC Mos or Hexfets as IRC likes to call them.

jakelm

Can you guys learn me something real quick?

Looking the MOSFET in pictures and on my older Hafler amp, I believe what I saw was, sorce gate and dump, 3prong. I noticed your bi polar only has 2 prongs. Why is that? Or am I thinking of something totaly different?

or is this stricly design for the board?

ben62670

jakelm wrote: »

Can you guys learn me something real quick?

Familiar with the MOSFET, sorce gate and dump, 3prong. I noticed your bi polar only has 2 prongs. Why is that? Or am I thinking of something totaly different?

or is this stricly design for the board?

The case is the 3rd leg. 85VDC taught me that one:eek:

heiney9

ben62670 wrote: »

They are actually hexfet. I like my 585 over my 5800 anyday.

Hexfets are used for the front end not the final output stage on the MosFet Adcoms. 5xxx series.

MosFets can have the exact same T03 metal can and I believe the 5800 is MosFet, just can't remember and am too lazy right at the moment to look it up.

5802 is MosFet.

heiney9

jakelm wrote: »

Can you guys learn me something real quick?

Looking the MOSFET in pictures and on my older Hafler amp, I believe what I saw was, sorce gate and dump, 3prong. I noticed your bi polar only has 2 prongs. Why is that? Or am I thinking of something totaly different?

or is this stricly design for the board?

NM, reading comprehension is a bit low right now:eek:

Systems

jakelm wrote: »

I noticed your bi polar only has 2 prongs.

Bi polars also have 3,the base ,emitter and collector.

Systems

Hafler where one of the first to use Mos Fets ,I think Mr Borbely designed the early Mos stuff for them.

Systems

heiney9 wrote: »

MosFets can have the exact same T03 metal can .

Yes I think that has been pointed out a couple of times already.:rolleyes:

jakelm

Well, I couldnt tell you which was better, but I do know I cant kill my Hafler. I dont know if that has anything to do with the tranny's. I can cook an egg on it, but cant kill it..

Systems

jakelm wrote: »

Well, I couldnt tell you which was better, but I do know I cant kill my Hafler. I dont know if that has anything to do with the tranny's. I can cook an egg on it, but cant kill it..

Yep they are robust and reliable once you get them soldered into the circuit.They are very static sensitive and must be handled with care during assembly.

jakelm

GV#27 wrote: »

Yep they are robust and reliable once you get them soldered into the circuit.They are very static sensitive and must be handled with care during assembly.

Well its a good thing I didnt assemble it, becides installing new input caps and new PC caps and power switch. I have taken it apart a million times.

I handle nothing with care...lol

But that old black metal case is hard to dent and scratch.


sorry for the hijack Ben... carry on..

I thought I smelt a debate brewing.... to stop on my acount...lol

Systems

ben62670 wrote: »

IRF244, and IRF9240

Is that the part number on those outputs?Then they is Fets.

heiney9

GV#27 wrote: »

Yes I think that has been pointed out a couple of times already.:rolleyes:

Alrighty then :rolleyes:

ben62670

GV#27 wrote: »

Is that the part number on those outputs?Then they is Fets.

Ya got me:D

Non common ground either. Can the grounds be tied together?

Systems

ben62670 wrote: »

Ya got me:D

Ok you posted 2 part numbers IRF244 and IRF9240 .Then later you added the pick of your amps output transistors.I can't read the numbers on those outputs but if it is the stated part numbers then they are Fets.Comprondy?:D

Non common ground either. Can the grounds be tied together?

Nope.

heiney9

ben62670 wrote: »

Ya got me:D

Non common ground either. Can the grounds be tied together?

Yes they can. 5800, 5802, 565 all can be tied together. Ask DarqueKnight and HearingImpaired. I would assume the 585 could be too, but that's one I've never checked on.

H9

ben62670

GV#27 wrote: »

DNope.

Please!!!!!!!!!!!!!!!!
Those are the correct part numbers from the TO3 Misfits:p I looked up the data sheet on them, and they called the hexfets I must resit the urge to tie grounds together:mad::mad::mad:
Well SDA cable disconnected the 5800 hits faster than the 585, but sounds much more edgy which really sucks, because I would like to drive the stereo array with the smoother GFA-585, and the dims with the 5800, but that will not work:(

BTW... spell check substitutes misfits for mosfets. I think that is kinda funny:D

heiney9

ben62670 wrote: »

Please!!!!!!!!!!!!!!!!
Those are the correct part numbers from the TO3 Misfits:p I looked up the data sheet on them, and they called the hexfets I must resit the urge to tie grounds together:mad::mad::mad:
Well SDA cable disconnected the 5800 hits faster than the 585, but sounds much more edgy which really sucks, because I would like to drive the stereo array with the smoother GFA-585, and the dims with the 5800, but that will not work:(

BTW... spell check substitutes misfits for mosfets. I think that is kinda funny:D

Contact Adcom abut the 5800, but I am 1000% sure the 5802 and 565 can be tied together. The 5802 is just an updated version of the 5800 and the topology is essentially the same. They moved the cooling fins outside the case and got rid of those twin fans and tunnel effect cooling. They did some tweaking with the 5802 but it's essentially the same as the 5800. Both are Nelson Pass enhanced designs.

H9

ben62670

heiney9 wrote: »

Yes they can. 5800, 5802, 565 all can be tied together. Ask DarqueKnight and HearingImpaired. I would assume the 585 could be too, but that's one I've never checked on.

H9

Don't have to with the 585. All grounds are tied together internally:)

OK It's going to kick A$$, or I am going to smell smoke. At 2.6ohms this is a confirmation test of the safety of tying ground together on 5xxx MOSFET amps:D

ben62670

No Smoke! Sounds fine. A little edgy, but I am listening to Sting, and he records a little hot.

Systems

ben62670 wrote: »

Please!!!!!!!!!!!!!!!!

Those are the correct part numbers from the TO3 Misfits:p I looked up the data sheet on them, and they called the hexfets

As I mentioned earlier IRC (International Rectifier) call their Mos Fets HEXFETS they are the same thing:)

I must resit the urge to tie grounds together:mad::mad::mad: I

Amps that have bridged output stages should not have their negative terminals joined.Don't know if your 5800 uses such an output stage though.But is there not a special cable for using non common ground amps with SDA's.?

heiney9

GV#27 wrote: »

Amps that have bridged output stages should not have their negative terminals joined.Don't know if your 5800 uses such an output stage though.But is there not a special cable for using non common ground amps with SDA's.?

None of the 5xxx series (2ch) have bridged output stages. Some of the HT amps might to configure for a subwoofer, etc.

The only bridgeable 2ch amp from Adcom was the 555 and that would be a no no (as Engtaz found out ) to tie the terminals together when running (2) a mono blocs.

Again some of their HT amps had 1,2 or 3 channel configurations so I'm not counting those. Not sure if the original GFA1 and GFA2 were bridgeable. I've never had reason to learn much about those very first Adcoms.

AI-1 is the special cable to use with non-common ground amps that CAN"T have their negative terminals tied together.

H9

hoosier21

ben62670 wrote: »

No Smoke! Sounds fine. A little edgy, but I am listening to Sting, and he records a little hot.

a little? toooooo szippy for me on most of his.

Systems

heiney9 wrote: »

None of the 5xxx series (2ch) have bridged output stages. Some of the HT amps might to configure for a subwoofer, etc.



H9

Many high powered amps have bridged (also called balanced) output stages so that they can get the 500 watt output.Each of the 2 channels is made up of a bridged pair of output stages. Bryston, Pass Labs, Musical fidelity all do this on their bigger amps.

heiney9

GV#27 wrote: »

Many high powered amps have bridged (also called balanced) output stages so that they can get the 500 watt output.Each of the 2 channels is made up of a bridged pair of output stages. Bryston, Pass Labs, Musical fidelity all do this on their bigger amps.

I agree, but Adcom's, to my knowledge, aren't set up this way and can have the negative terminals strapped to accommodate SDA's.

DarqueKnight ran his 5802 strapped before getting an AI-1 cable and Hearing Impaired strapped his 565's when he had them. I believe there is a member who has a 5500 strapped for his SDA's as well.

The 5500, 5800, 5802, 565's (of course they are mono's) are all Non-common ground designs. It's my understanding that because they have a secondary or multiple secondary windings (rahter than 2 separate transformers) in these models they don't share a common ground at the speaker output. But there isn't an issue sharing the ground by strapping.

H9

Systems

Damn that is just way too many 5** something or other model numbers to keep track of.

heiney9

GV#27 wrote: »

Damn that is just way too many 5** something or other model numbers to keep track of.

LOL-

5200- common ground; no secondary trans winding
5300- " " " " " "
5400- " " " " " "
5500- Non-common ground; secondary trans winding(s); strappable
5802- Non-common ground; secondary trans winding(s); strappable
565- Mono Bloc non-common ground by design; strappable
585- Not sure but Ben states it has a common ground.
535, 545, 555 common ground
555- if run in bridged mode is not common ground and the neg terminals can NOT be strapped.

Disclaimer: this is what I've learned doing some research here and at DIY audio. If in doubt either measure using VOM at the output terminals or contact Adcom. I will not take any responsibility for the above statements being inaccurate.

H9

Systems

Apparently you don't suffer from alziemers to remember all of that.I have to stick to the numerically much simpler Bryston line,2B, 3B,4B,6B,9B all common ground. 7B,14B,24B,28B non common ground and not strappable.

jakelm

Very easy way to find out if its common ground. Ben, you already have the top off. Put the meter to it.

Face

Or just hook it up to SDA's.