• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

PL519 PP design

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi

I´ve searched a lot for info on PL519 (or PL/EL509) amps, but almost everything I found is about OTL amps.
Thing is that I bought a bunch of PL519 today for a very nice price, and I want to put them to use in a bass guitar amp project
that has been floating around for a while.

My question: Would a pair of PL519 be a good match for a Hammond 1650T (1,9k 120W) OPT, with about 450V on the plates?

I know Bruce Rosenblitz has designed something similar to this, does anyone have a schematic or some relevant infor about that design?

I´m kinda stuck to the 450-500V plate voltage, since that is what my in stock power transformers delivers and I don´t want to buy a new one.

Cheers
/Daniel
 
I have a schematic i can send you, its of the amp i am building, 150w PK uses PP el509/519 . As i understand it, it uses a 12ax7 for an input tbe, a 12at7 for the phase splitter. These drive 2 el509's in PP connected to a hammond 1650t . 6bm8's for screen regulators for the el509s.

I have built and today tested the phase splitter sections for the left and right channels. The PCB's i madequite nice, and saved a LOT of time. I have not yet tested the screen regulator portion. It is not yet complete, i am awating some back ordered parts. I also made a PCB for this section.

Unfortunatily, i think the PCB files were lost when my computer crashed. I may still have a hard paper copy i can scan for you.
Oh i hope you dont mind the 700v B+, be carefull!!!
Tom
 
Sweep tubes are great.

Lemme see here...

500V minus 50V typical saturation = 450V peak, sinewave = 318.2Vrms = 636.5V across 1.9k primary = 213W (426W squarewave). Hmm, sounds like 500V for that tranny will be more than enough ;)

It'd have to run at 600mA bias per tube though, class A is out of the question!
Class AB might run, lesse, it's what 30 or 40W max.? Let's say 60mA bias per tube. That leaves a peak of what, maybe 800mA the tube has to reach, you can check the datasheet for what screen voltage is required. Probably not much given this beefy type.

Tim (master of the SWAG)
 
Sch3mat1c said:
Sweep tubes are great.

Lemme see here...

500V minus 50V typical saturation = 450V peak, sinewave = 318.2Vrms = 636.5V across 1.9k primary = 213W (426W squarewave). Hmm, sounds like 500V for that tranny will be more than enough ;)

It'd have to run at 600mA bias per tube though, class A is out of the question!
Class AB might run, lesse, it's what 30 or 40W max.? Let's say 60mA bias per tube. That leaves a peak of what, maybe 800mA the tube has to reach, you can check the datasheet for what screen voltage is required. Probably not much given this beefy type.

Tim (master of the SWAG)

I made 30W PP amplifeir with triode connected PL509s. It was nice, but not as good, as the 6550 sounds in triode mode.
HT=300V, -Ug1=75V, bias 100mA. Raa=2k2. the output is little more than 30W. But it needs very heavy driver stage to get the large driving signal.
In tetrode mode I used HT=460V, Ug2=150V (with VR150 regulator), Raa=2k2 (same output transformer). The output is about 120W, if the power supply is large enough. 140W possible, with regulated HT. Bias is about 50mA class AB.
PL509 is very nice valve. Long lasting, heavy, and can handle almost anything. Due the large cathode, it can useful up to 1.4A peak.

sajti
 
460V B+ and 2,2k Ra-a=120W, that´s very interesting!

I guess 1,9k Ra-a would work just about as good as 2,2k, and I have a few beefy power transformers that puts out 450-500V with a lot of current.

Too bad I´ve already started on my 4x807 project, but it´s never too late to change:D
 
PL509/519/40KG6

I have been using these tubes for over 30 years and started the revolution in audio, so suddenly everyone is finaly waking up.

In pairs push pull Class B 180 watts is achievable. Class AB1 140 reliable watts is achievable . Pure Class A is 35 watts period.

Remember electrons have no memory. They don't know where they have been!
 
Fuling said:
460V B+ and 2,2k Ra-a=120W, that´s very interesting!

I guess 1,9k Ra-a would work just about as good as 2,2k, and I have a few beefy power transformers that puts out 450-500V with a lot of current.

Too bad I´ve already started on my 4x807 project, but it´s never too late to change:D


I have another schematic for PL509, which give 120W, with HT=400V, and Vg2=200V, I don't know the Raa, but I can check it.

sajti
 
Dear Fuling!

I've got a PL509 PP amp. (monoblock)
It called "APX-100", and manufactured in Hungary, by BEAG, in 1975. It was produced to feed 100V audio lines. So I rewinded the output transformer. Now it can deliver 120W-RMS into 8ohm. (before it delivered 100W to 100ohm).
The geniune tubes were two ECC808 (=ECC83), and a pair of PL509.
When I modified it to 8ohms output, I changed the driver tube to ECC82.
The anode voltage (for the output tubes) is 460V, G2 voltage is 410V.
The primary impedance of the output trafo is 2,5Kohm.

In the evening I will make some fotographs of the amp, and I will attach the schematic, if you are interested.

Otherwise the amp is a really oversized! It has a huge box (400*330*180), and huge trafos. The weight is about 20Kgs. After 30years it still in perfect condition. It was working only 60 hours... The output and the first tubes are still the geniune tubes... They were inserted 30 years ago in the factory...

Other datas: freq. response: 30Hz-15KHz (+/-1dB), input: 0,775mV (0dBm), 0,22Mohm
power consumption: 320VA, signal/noise: better then 60dB
 
Re: PL509/519/40KG6

AV8R said:
I have been using these tubes for over 30 years and started the revolution in audio, so suddenly everyone is finaly waking up.

A question out of more-than-curiosity: I first saw this family of tubes used in the '70s (Audionics BA150 with 6LF6). I've been using 6LF6 since then in a screen-drive mode, basically as a zero-bias triode. But, as you know, that tube is fairly much unubtainable now at any kind of reasonable price. Have you used the 509/519 in that sort of configuration?
 
el 519

This is my amplifier , i have built 9 years ago and still working with the same output tubes [ soviet el519 ]:smash:
 

Attachments

  • 519.jpg
    519.jpg
    46.1 KB · Views: 2,077
NotInTheMafia said:


Just so you all know that 1.4A pk is for the NOS real PL509, the newer Russian equiv is a much lower current rating.

I have about 20pcs of Tungsram PL509/519. They are very nice tubes. Unfotunately not the best for audio, but very useful for series pass application in regulated PSU. And I used PL509s as recitifier tubes, connected as diode.
 
Ex-Moderator
Joined 2003
NotInTheMafia said:
Just so you all know that 1.4A pk is for the NOS real PL509, the newer Russian equiv is a much lower current rating.

Do bear in mind that the original ratings implied a 625 line television system where the peak current was required for an absolute maximum of 12us out of 64us. In other words, it was a pulse rating that would not remove the space charge. Not the same thing as a continuous rating - it translates to 12/64 x 1.4 = 260mA. Still pretty impressive for a 30W valve, mind.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.