Hello from Jakarta

Post by **Nick** » Tue Nov 15, 2011 8:04 pm

Dgentolet wrote:Cressy,
Considering the price different of around US$ 1000 and sound improvement, it is really worth to use NOS version.
If that the case,

You may be better off never hearing a nos pair. (not entirly joking).

IslandPink · Post by **IslandPink** » Tue Nov 15, 2011 9:31 pm

The KR ones may be very good. Their 300B's are excellent and mine have done 3500 hours + with no problems . Still, I'm sure original PX25's will still be the best sound-wise .

simon · Post by **simon** » Tue Nov 15, 2011 10:22 pm

Nick wrote:
Dgentolet wrote:Cressy,
Considering the price different of around US$ 1000 and sound improvement, it is really worth to use NOS version.
If that the case,
You may be better off never hearing a nos pair. (not entirly joking).

Tend to agree with that.

Dgentolet · Post by **Dgentolet** » Wed Nov 16, 2011 6:25 am

You guys really drive me crazy to the PX25 NOS

pre65 · Post by **pre65** » Wed Nov 16, 2011 9:18 am

You might like to ask yourself a question.

Why, if the NOS PX25 is supposed to be so good, does no one on this forum actually (at this very moment) use them.

Paul Barker · Post by **Paul Barker** » Wed Nov 16, 2011 9:42 am

I can answer for myself only.

Because in the past when I brought them to events on two occasions the filaments broke. A further one broke at home. All of these were balloon's.
the breakages were not due to operating point they were due to transporting them. I would never post a pair and I would never pay for a pair which would be posted to me.

So I made a decision 5 years ago that they never get transported anywhere due to the difference between their value with an intact fimalent and their value with a broken filament.

I like their sound better than the 2a3 px4 300b (proper original Western electric, not recently made Western Electric) and GET4C. The only valve of similar standing in my heart is the oxide coated 211 and the VT25/VT62.

today would I buy a pair of nos ballon px25's?

NO, for my budget price has exceeded the difference in sound benefit over afforementioned valves.

Would I sell any? Yes at full market price to someone who turns up at my door with cash listens to them at that moment and the moment they leave my hands (not my property), full responsibility for their condition rests with the new owner. Otherwise they will sleep safely in their drawer.

simon · Post by **simon** » Wed Nov 16, 2011 12:29 pm

pre65 wrote:You might like to ask yourself a question.

Why, if the NOS PX25 is supposed to be so good, does no one on this forum actually (at this very moment) use them.

I think our Steve S does though. But if I had Steve's valve collection I might too.

Their sound quality is without doubt, but the only pair I've seen for sale was in Akihabara priced at a cool thousand quid. Scarcity and desirability force the price inevitably.

Or do you go for GM70s say, £25 a pair last time I looked and literally rooms full laying around the old soviet empire. Might not sound as good maybe but much easier to replace. You pays yer money and makes yer choice.

Post by **Nick** » Wed Nov 16, 2011 8:18 pm

Much the same reason why there are not many Ferrari owners around. Can't be used to infer that they ain't no good.

pre65 · Post by **pre65** » Wed Nov 16, 2011 11:56 pm

Nick wrote:Much the same reason why there are not many Ferrari owners around. Can't be used to infer that they ain't no good.

True, but high price and limited availability does not (necessarily) make them (Ferrari) the best.

I'm not sure I would recommend a monkey type circuit to someone who is just a circuit copier (forgive me if that's a wrong assumption) as unless you copy everything 100% things can easily go wrong.

When I was "monkeying about" it was most frustrating how changing one thing messed up other areas.

Is there a "classic" PX25 circuit to help this new member achieve his ambition ?

Dgentolet · Post by **Dgentolet** » Thu Nov 17, 2011 1:08 am

Paul, have you compared the sound of PX25 NOS with 2A3 single plate ?

If PX25 NOS is such a fragile tube, it is really scary.

Mike H · Post by **Mike H** » Thu Nov 17, 2011 4:38 pm

pre65 wrote:Is there a "classic" PX25 circuit to help this new member achieve his ambition ?

I found this, Wireless World circa 1934

http://mike.wepoco.com/Home/retro-geeke ... -Amplifier

steve s · Post by **steve s** » Thu Nov 17, 2011 7:39 pm

Dgentolet wrote:Cressy,
Considering the price different of around US$ 1000 and sound improvement, it is really worth to use NOS version.
If that the case,

that depends on how much spare cash you have...

the diffence between nos striaght sided px 25's and the old globes is quite a step, but building a first amp and expecting to get it to sound as close to as good as the valve could be.. is a challange,

the driver valves/ power supply/ rectifier valves/ output transformers/ method and quality of the valve coupling all have some quite dramatic effects, i`ve been using px4 and px25 for quite a few years and the sound of my amps has changed so much... whilst still using the same valves...

try building steve's 'rocky', with trioded kt66 or el34 for starters if you have not built anything before..
once you get that right you can progress on to the px 25, its really not any more difficult to build with .. but mistakes can be costly..

if you are an expert builder, i can supply some old px25's at reasonble rates.. i have a few..

cheers
steve

Paul Barker · Post by **Paul Barker** » Thu Nov 17, 2011 10:21 pm

Dgentolet wrote:Paul, have you compared the sound of PX25 NOS with 2A3 single plate ?

If PX25 NOS is such a fragile tube, it is really scary.

Not at the same time on the same system. But they are not similar the 2a3 is more like a PX4.

It will be considered by most be an unreliable general view but IMHO YMMV TIOLI PX4 has better high's, PX25 makes PX4 sound fat, but px4 makes 300b sound fat. Each step is an upgrade. Ultimate is balloon PX25. More like a 45 than a 2a3 but with greater power.

I doubt it is more fragile than any other valve of the same age.

Greg · Post by **Greg** » Thu Nov 17, 2011 10:43 pm

Paul,

It would be good for you (or actually for us) if you could change your plans and turn up at Owston on Saturday or Sunday. If you don't you'll be missed.

Greg

Cressy Snr · Post by **Cressy Snr** » Fri Nov 18, 2011 8:24 am

steve s wrote:[
if you are an expert builder, i can supply some old px25's at reasonble rates.. i have a few..

cheers
steve

Don't get me thinking again Steve

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