What are some good MOSFET amps?

HiFi Dude: Excellent Posts with Extensive Research. My sincere AK thanks! Such an educational pleasure!

The VSP Labs TransMOS amps have those beautiful starfish cooling that are reminiscent of the cooling fins in the Yamaha B2.

In one sense the Yamaha with their V FETS transistors are the Godfather (maybe accidental ) of the MOSFET sound.

Of course James Brown is still the Godfather of soul. Carry on HiFi Dude.
 
Is it true that in the Hafler implementation, FET was short for "Flame-Emitting Transistor"?

I'm not buying that label. I've had Hafler amps for the better part of 30+ years and that it _not_ the experience I've had with them.

Where, exactly, do you get this perception, please?

Cheers,

David
 
This thread got resurected and I read it for the first time. avionic, I hope the link you show here is still a good one. I can't get to anything accept .org, .mil and .gov sites right now.

I'm going to check it out when my tour is up in another week and a half. I'm very interested in that amp design but will have to find out if the Hitachi MOSFET's are still readily available.

That link is still working for me.
 
This thread got resurected and I read it for the first time. avionic, I hope the link you show here is still a good one. I can't get to anything accept .org, .mil and .gov sites right now.

I'm going to check it out when my tour is up in another week and a half. I'm very interested in that amp design but will have to find out if the Hitachi MOSFET's are still readily available.

Renesas/Toshiba should still be available or exicon ( see post #100.)

http://www.bdent.com/catalogsearch/result/?q=2SK1058
http://www.bdent.com/catalogsearch/result/?q=2SJ162
 
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Is it true that in the Hafler implementation, FET was short for "Flame-Emitting Transistor"?
I'm not buying that label. I've had Hafler amps for the better part of 30+ years and that it _not_ the experience I've had with them.

Where, exactly, do you get this perception, please?
Sorry, I don't own a Hafler.

A good friend of mine has a pile of DH500s, DH200s, and an XL280. He bought all but one--his first--off of eBay. Number One was the kit version, purchased from a dealer in about '82 or '83. Some of his "used" ones are the "professional" version. Most were used hard, put away wet. "Flame-Emitting Transistor" is his term, I merely borrowed it.

Sellers claim they work fine. Sometimes they do. Once, he pulls the lid on a DOA unit, and discovers that the lead from an output transistor has burned off. Seller claims "shipping damage", of course.

He's had more than just that one where the output transistors have popped. They don't play music when the smoke gets out.

Once repaired, the units work in his home system without problems. I think the output transistor failures are from carelessness with cables, and from being overdriven by drunk DJs in nighclubs. I've heard that the input boards are fragile, though. He's bought some from Musical Concepts as replacements.

He loves 'em so much that he convinced at least two of his friends to buy multiple DH500s to power their systems. All these amps were delivered to him, he checked 'em out, fixed what needed repair, and only then turned them over to his buddies.
 
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yep...i'm running one...very happy

Had a Hafler XL-280 before that and the B&K blows it away...


B&K made some nice gear. I bought a set of B&K M200 Sonata's new in 1992. I also owned an ST140 and later an AV5000 SII. However as you can see by the equipment in my signature I found the opposite to be true for Hafler versus B&K sound quality in my system.
 
Another good MOSFET amp to DIY is the Crescendo "millennium edition" version...

1982 original version came with some instability problems, nevertheless it still made its followers in many countries. The 2001 version had the ills cured and the amp is fully protected and stable.
LatFETs K1058 / J162 were used in this version.

Link: http://www.raylectronics.nl/pdfs/Crescendo_Millennium_en.pdf

4l6irq.jpg
 
Is it true that in the Hafler implementation, FET was short for "Flame-Emitting Transistor"?

I have a Hafler Pro1200 that has been powered up for over thirty years. Never been turned off unless the power went out or it was moved. Works perfectly, It drives a pair of JBL 4406 for an editing station.
 
I have a Hafler Pro1200 that has been powered up for over thirty years. Never been turned off unless the power went out or it was moved. Works perfectly, It drives a pair of JBL 4406 for an editing station.


Wow that thing has used a lot of juice over 30 years. Reliable yes, efficient no! The Pro1200 manual states 60VA quiescent. That comes out to about 1.44KWH a day so 15,768 KWH's over 30 years of idling. That is more electricity than my 2400 sq/ft house with a family of four used in 2014. I guess your avatar is appropriate. If you cannot tell, I'm too cheap to leave my gear powered on all the time. :yes:
 
Wow that thing has used a lot of juice over 30 years. Reliable yes, efficient no! The Pro1200 manual states 60VA quiescent. That comes out to about 1.44KWH a day so 15,768 KWH's over 30 years of idling. That is more electricity than my 2400 sq/ft house with a family of four used in 2014. I guess your avatar is appropriate. If you cannot tell, I'm too cheap to leave my gear powered on all the time. :yes:

Interesting. I try to be pretty thrifty about power consumption. The amp is at the bottom of a gear rack with a burned out switch light. I guess I just do not think about it. It is just there first thing in the morning when I need it.

Funny about the avatar!
 
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Wow that thing has used a lot of juice over 30 years. Reliable yes, efficient no! The Pro1200 manual states 60VA quiescent. That comes out to about 1.44KWH a day so 15,768 KWH's over 30 years of idling. That is more electricity than my 2400 sq/ft house with a family of four used in 2014. I guess your avatar is appropriate. If you cannot tell, I'm too cheap to leave my gear powered on all the time.

Had to laugh... waste of energy that would put bucks in your pocket for this hobby. Unless you listen 24/7 and don't sleep.
 
Had to laugh... waste of energy that would put bucks in your pocket for this hobby. Unless you listen 24/7 and don't sleep.

Did you read the part where I said it is a video editing audio monitor amp? I work up to 15 hours a day editing video and mixing audio. Since it is a business, a portion of the PGE bill is a tax write off. I don't look at it as not being able to buy Craigslist speakers or something for my 'hobby'. It is really not that big of a deal money wise. It's like leaving the porch light on.

This is how I learned to work in Radio production, the coffee is always hot and the amps are always warm.

The point Mond made about my ReddyKillowatt avatar is funny though.
 
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One of my favorite Mosfet amps for location house PA is an Anchor Audio AN1000X, rugged and cheap. I use two with matching passive speakers on stands for nice clean audio for groups of up to 200 people. They are small enough to pack in Pelican cases and stash in an overhead bin when flying.
 
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Had to laugh... waste of energy that would put bucks in your pocket for this hobby. Unless you listen 24/7 and don't sleep.

You'd be surprised just how much power is lost in a house. Things that you dismiss as minimal have a big impact. Back in 2005 I was trying to get my house energy efficient. I could never get the low usage times of the year, spring and fall, to go below ~1200 kwh's/month. I dismissed the usage of the 4 computers I had in the house as minimal and I left many of them on all the time. I finally bought a Killawatt meter and started measuring. It didn't take long to figure out that the desktops needed to be OFF when not in use. I also found two old fast chargers on my work bench that together were drawing close to 40W just sitting there with no battery on them. I also had a couple of old tube TV's that drew an unusually high power when off. The first month after I snooped out the house my usage dropped to 800 kwh's.

I did the same for my father back then. He had an old rusted 70's fridge (a green one) in the garage that he kept his beer in. We found out that old fridge was costing him about $30/month in electricity just to keep beer cold. Needless to say that fridge was disconnected and trashed that same day.

Anyway, a lot of audio gear is notoriously inefficient. Some big amps out there are very power hungry at idle. My Hafler XL-600 pulls well over 200W from the wall at idle. My Aleph Class A mono's draw 180W per channel. I usually start my amps up 30 min or more before I plan to listen to give them time to warm up and stabilize and then shut them down when I am done listening for the day.
 
You'd be surprised just how much power is lost in a house. Things that you dismiss as minimal have a big impact. Back in 2005 I was trying to get my house energy efficient. I could never get the low usage times of the year, spring and fall, to go below ~1200 kwh's/month. I dismissed the usage of the 4 computers I had in the house as minimal and I left many of them on all the time. I finally bought a Killawatt meter and started measuring. It didn't take long to figure out that the desktops needed to be OFF when not in use. I also found two old fast chargers on my work bench that together were drawing close to 40W just sitting there with no battery on them. I also had a couple of old tube TV's that drew an unusually high power when off. The first month after I snooped out the house my usage dropped to 800 kwh's.

I did the same for my father back then. He had an old rusted 70's fridge (a green one) in the garage that he kept his beer in. We found out that old fridge was costing him about $30/month in electricity just to keep beer cold. Needless to say that fridge was disconnected and trashed that same day.

Anyway, a lot of audio gear is notoriously inefficient. Some big amps out there are very power hungry at idle. My Hafler XL-600 pulls well over 200W from the wall at idle. My Aleph Class A mono's draw 180W per channel. I usually start my amps up 30 min or more before I plan to listen to give them time to warm up and stabilize and then shut them down when I am done listening for the day.

I use Revogi Blue tooth smart plugs on all my vintage gear. Easier than un-pluging them when the plugs are hard to get to. Plus pulling and inserting plugs into a socket over and over loosen the connection. Plus they tell you how much energy is used and you can addd your energy cost to figure out how much you spent using the amps etc.

https://stacksocial.com/sales/bluetooth-smart-meter-plug

or the wifi power strip, I use thid for my CRT projector, its great to warm up the PJ on my way home from work to watch a movie.

https://stacksocial.com/sales/revogi-smart-power-strip-2

Nashou
 
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