phase linear 400

[62vauxhall]

i was told that it was better to monoamp 2 200 series than dh500...by and old dynaco and hafler engineer...but dont know enough to know which ones nor how they are modified to monoamp..
maybe there is info here???
congrstulation!!!
do you like hafler gear??

For sound quality? Short answer is yes.

That DH101 is the only piece of Hafler gear I still own. It was included for free with a NAD 2100 that I bought off Craigslist for $75. I wasn't really interested in the pre-amp but did not refuse it. This was all before learning of this Pheonix forum and back then I was using from time to time a Hafler DH220. That cost $125 and was "modified" by the seller's brother so as to power some Magnepan's better than if it was stock. Or so the story went.

In any case, the DH220 never missed a beat and in all honesty, I could have (should have) been happy enough with it and logically, there was no practical reason to change. But when my 700B got WOPL-ized, I saw no point in hanging on to the DH220 so it went with a bundle of gear as an even trade for a Sony TA2000 pre-amp. Included in that bundle was another Hafler piece, a DH110 preamp.

In general, I respect Hafler gear but of the three pieces, which I owned simultaneously, I liked the DH110 the least. I thought the DH220 was a really good amplifier and I should not have disposed of it on whim.

I keep the DH101 because of what the parts cost and all the time I spent refurbishing it over the years. I have far more into it than what it is worth as a working unit. It's quirky because it's so cheaply constructed but is somewhat iconic.

After having been inside those three Hafler items, something I found appealing was that they were not crowded internally so relatively easy to work on.

 

[gene french]

For sound quality? Short answer is yes.

That DH101 is the only piece of Hafler gear I still own. It was included for free with a NAD 2100 that I bought off Craigslist for $75. I wasn't really interested in the pre-amp but did not refuse it. This was all before learning of this Pheonix forum and back then I was using from time to time a Hafler DH220. That cost $125 and was "modified" by the seller's brother so as to power some Magnepan's better than if it was stock. Or so the story went.

In any case, the DH220 never missed a beat and in all honesty, I could have (should have) been happy enough with it and logically, there was no practical reason to change. But when my 700B got WOPL-ized, I saw no point in hanging on to the DH220 so it went with a bundle of gear as an even trade for a Sony TA2000 pre-amp. Included in that bundle was another Hafler piece, a DH110 preamp.

In general, I respect Hafler gear but of the three pieces, which I owned simultaneously, I liked the DH110 the least. I thought the DH220 was a really good amplifier and I should not have disposed of it on whim.

I keep the DH101 because of what the parts cost and all the time I spent refurbishing it over the years. I have far more into it than what it is worth as a working unit. It's quirky because it's so cheaply constructed but is somewhat iconic.

After having been inside those three Hafler items, something I found appealing was that they were not crowded internally so relatively easy to work on.

fascinating.....
thanks for sharing your experiences!!!
i will dip my toes in the water if i can find a deal i can live with...i did just bid on another 400...but it was ridiculously low..i wint be getting it....lol
i do so much enjoy the knowledge shared and of course the war stories!!!

 

[J!m]

I had a DH220 before my first Counterpoint.

Not a fair comparison at all but I had no problems with it.

 

[gene french]

never ending ....

lol

 

[gene french]

dont know if i did good or something really stupid...
bought 2 working hafler p230s...which has built in mono bridge for 355 watts per channel...
i was told these are well designed units...
time will tell...

 

[gene french]

into 8 ohms...

 

[gene french]

the latest 400 arrived today....did not look too beat up....i opened it...looked around...removed the meters...looking for obvious omens...
i thought i saw marvin peeking in the window....i cant be sure....plugged it into the dbtester...as you would expect burned bright....
removed top row of outputs on left channel....bulb dimmed as expected...repopulated....retested...i did have a fuse too short for the ac input...
and left channel fuse showed open...kinda expected a bad output...after changing one f 909 i .tested the offset....still rail voltage on left side...so started the board disassembly....so far...
6 shorted diodes....6 charcoaled resistors...both bias resistors were bad...i only have one replacement...i did order 4 more with the pclips.......flipped the amp on its fins to get at diodes to test...under the bottom ps cap was a faded barely legible 220 sticker...could not see it in normal position....it was one the underside of the cap...looked at the transformer...a 240v ac 50 hz sticker on it...
it does not have the european 220 plug...just the normal 2 prong plug like all of my non wopled 400s....
i see an extra wire from the shell side of the ac input fuse holder .... was pinched under the top cap....did not trace it down...but it appears to go to the thermal switch....where there is an extra wire soldered to one leg...
i have a running 400 8 fin open waiting for joes ps cap upgrade....i can look and see if i see anything different....
other than that extra wire....it looks like every other 400 that i have....
can someone enlighten me.....please...
my dodge steering gearbox seal kit arrived along with the other tie rod end....will take it to the shop at 7:30 in the morning and scrounge a ride home....i really dont expect it back tomorrow evrning...no matter....so with nowhere i can go...will have plenty of time to continue on the latest 400....

 

[George S.]

Gene, look at the 400 S2 service manual and you'll see a nice graphic for wiring the dual primary transformer, if that's what you have.
I thought all Series 1 were 110 VAC only, but the 2000 S1 preamp carcass I recently purchased appears original with a dual primary.
So far all my Series 2 gear has had the dual primary transformer.

 

[George S.]

Best photo I can find of the dual primary 400 S2 transformer configured for 110 VAC. The primaries are connected to the wall power cord at those yellow wire nuts. I was testing the configuration for what primary goes to Line and Neutral for lowest noise.

 

[gene french]

thank you mr. george...
i will study ..

 

[George S.]

For those who have a IEC socket and want to determine which primary should be connected to Line for lowest noise, here's the link to the thread where Joe explains this. So far every dual primary transformer I tested shows lowest noise with the striped primary wires to Line.
I've not yet to tested a non dual primary transformer.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8

 

[Gepetto]

For those who have a IEC socket and want to determine which primary should be connected to Line for lowest noise, here's the link to the thread where Joe explains this. So far every dual primary transformer I tested shows lowest noise with the striped primary wires to Line.
I've not yet to tested a non dual primary transformer.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8

That would make sense George because every manufacturer of transformers has a winding sheet that dictates how to wind making them all turn out quite consistently.

 

[George S.]

Cool. Even the 2 different PL2000 S2 transformers I tested were the same, lowest noise with the striped primary connected to Line.

 

[gene french]

pics of the transformer...
recapping pl14...
will investigate the setup probably tomorrow...
parts on order...

 

[gene french]

i will try to explain what i got....quite different from the other transformers in the 8 fins
2 holes on bottom of xformer....\
left hole has 4 wires coming out....2 go to ac on recitfier....other two go to bus bar between big caps....
right hole also has 4 wires coming in....2 go to shell on ac inline fuse...2 go to the left pole on the thermal switch...
the ac line from shore power ....
one line goes to right pole on thermal switch
other line goes to tip of ac inline fuse....
there was sever damage to the pl14....
6 toasted resistors
1 resistor was shattered in two...
for a total of 7 ....
6 open or shorted diodes....
8 bad transistors....
included is the pics....
if someone can tell me what i am looking at....
i would appreciate it...

 

[gene french]

pics....
when i plugged it up...before i discovered 240 stickers (had no idea that existed)...
rail voltage on left channel was around 75 volts...
something feels very wrong...

 

[George S.]

Looks like you may have the earliest version dual primary transformer ever. You may have a very bad storage cap pulling the B+ or B- down.
So back to fundamentals. Check your B+ and B- rails.
Disconnect the B+ and B- from the caps.
With DMM set to VDC, negative lead on copper buss bar, positive lead on the B+ should be read 80 VDC.
Positive lead on B- should read -80 VDC.
Keep that negative lead on the buss bar and caps disconnected!
If all good, issue is downstream. If not good, issue is upstream.

 

[gene french]

Looks like you may have the earliest version dual primary transformer ever. You may have a very bad storage cap pulling the B+ or B- down.
So back to fundamentals. Check your B+ and B- rails.
Disconnect the B+ and B- from the caps.
With DMM set to VDC, negative lead on copper buss bar, positive lead on the B+ should be read 80 VDC.
Positive lead on B- should read -80 VDC.
Keep that negative lead on the buss bar and caps disconnected!
If all good, issue is downstream. If not good, issue is upstream.

do i plug it into 120 or 240???
thats why i am asking...
the black wires are not labeled....
the soldering to the thermal resistor and shell of the left rail fuse holder does NOT look factory....
i will try tomorrow....
there was a lot of repair to the pl14....
it is done now...and i am sure it is ok...
but, i dare not plug it in...
no bias transistors....would smoke outputs...
and if the voltages is wrong....maybe that is where the damage starts....
i have new caps coming....2 sets to be exact....
but, i am afraid to plug them in if there is a possibility the old ones are bad....dont need 4 bad caps...
thanks mr. george....
i am sure it will get figured out...
i never knew this existed....
dont remember seeing it in the service manual....
i will check again....
thanks you....

 

[George S.]

Oh, I see your point. Well, from what I see, it looks like it should work at 110 VAC.
Disconnect those old caps and test the power supply section for B+ and -.
If they had a long wire disconnected from the thermo switch, and a short wire disconnected from the main fuse holder, and those two wires were connected together, then I'd say it was wired 220 VAC based on the S2 wiring graphic.
But what's up with the white wire with what may be a stripe. Looks like one goes to the buss bar, so that's the center tap. Is the other connected to the back wall or buss bar?
The S2 dual primary transformers have a single black stranded center tap wire.
The S1 standard transformers have two solid enameled wire center tap wires.
If both of those white wires go to the buss bar, your good. And of course the other two white wires are AC for the meter bulbs.
Disconnect the caps, lift those rail wires up so they don't short, and test. Your probably good.

 

[gene french]

i think its a dual primary and dual secondary...
4 wires in....6 wires out.. .with 2 being 5 volt tap...
i will study more