[justin w.]

Over the last few weeks, the SQ from my 009 / BHSE had changed ( less dynamic ) so I decided to change the quad of PH tubes I was using, and put in the second quad I'd got.
And the SQ sounds to be back to how it was when I first started using the first quad, so it sounded like that first quad were ready for packing up.

I'd been using that first quad for over a year, but I haven't been using my BHSE everyday, in fact there were times I only listened to it 2 or 3 times aweek.
So if I'd been using the BHSE more often, then those PH's might've not lasted as long.

While I'm happy with the SQ from my 009 / BHSE using the PH's, for what those tubes cost I'd have expected them to last a lot longer.
So, I've decided that once this second quad packs up, I won't bother getting anymore, I will however try and get hold of a quad of the Mullard or Holland XF4DD's I'm reading good things about.

You could have the old quad of tubes tested to see if they are still performing at their original spec.

 

[justin w.]

  This talk about the BHSE and failing tubes makes me wonder if it drives them particularly hard. I think these tubes are/were more commonly used for PA or guitar amps, for a headphone amp they should be more robust. Unless the new production is really that poor, or the circuit runs hot. 

see above post

 

[David1961]

  Hopefully you will have much better luck with your new tubes.  One of my Shuguang Black Treasure tube also died within three months.  The NOS tubes have proven to be very solid and reliable so far for the last 1.5 years.  Knock on wood!

 
I've a feeling purk, that this second quad of PH's will probably last the same time as the first, or they might even go before then.
Like I've mentioned, I am very happy with how they make the 009's sound, but I would've wanted them to last a lot longer.
 
As well as me having that second quad of PH's, I still have the stock mullard's and some SED's I'd got, and the place I got those SED tubes are selling Mullard XF4 single getters, but apparently double getters are supposed to be better, so does anyone know what the differences are between the two.
 
 
 

  This talk about the BHSE and failing tubes makes me wonder if it drives them particularly hard. I think these tubes are/were more commonly used for PA or guitar amps, for a headphone amp they should be more robust. Unless the new production is really that poor, or the circuit runs hot. 

 
There's been quite a bit written about the reliability of the PH's Earspeakers.
 
 
When I first got the BHSE, the tubes that came with it were the stock mullard's, however because I wasn't happy with how some songs sounded with my 009 / BHSE using those stock tubes, after about 5 months I change them to SED tubes.
Those songs did sound slightly better from using the SED's but I still wasn't completely happy, it was then I got the PH's.
 
Before getting the PH's I'd been using the SED's for over a year and they were still going strong, in fact I've heard the 007's with my BHSE while using the SED's and those songs I had problems with from the 009's, sounded very good with the 007's.
 
With me still having both the stock mullard's and SED's, I might end up getting a pair of 007's.
 
P.S. I did have the 007mk1's for 11 years which were being driven by the SRM-007t, but because I was so disappointed with how the mk1's sounded with that amp, I used them both as part exchange for the source I have.
 
 
 

You could have the old quad of tubes tested to see if they are still performing at their original spec.

 
The silver paint [ if that's what it is ] at the top of the PH tubes Justin, had faded to virtually see through, so there's noway I'll be using that first quad again, however how is testing tubes spec done ?

 

[FrankCooter]

  This talk about the BHSE and failing tubes makes me wonder if it drives them particularly hard. I think these tubes are/were more commonly used for PA or guitar amps, for a headphone amp they should be more robust. Unless the new production is really that poor, or the circuit runs hot. 

If memory serves me correctly, the EL34's in the BHSE are run with standing plate currents in the 20mA range. This is barely breathing for an EL34. Good ones should last 25 years or more at this rate.
 
The EL34 was one of the last major developments of the tube era. It was specifically designed to pack a lot of power and voltage handling ability into a relatively small package.
 
It was widely used for guitar amps  and PA systems, but it was also used extensively in audio by Fisher, Heathkit, Marantz, Dynaco, and others. The Dynaco ST-70, probably the most famous and widely built tube amp of all time, employed a push-pull pair of EL34's as outputs. The Marantz Model 9, which also uses push-pull EL34's is a serious contender for the best classic tube amp ever built.
 
The problem here is the inconsistent quality control of  new production tubes.

 

[Golfnutz]

   
I've a feeling purk, that this second quad of PH's will probably last the same time as the first, or they might even go before then.
Like I've mentioned, I am very happy with how they make the 009's sound, but I would've wanted them to last a lot longer.
 
As well as me having that second quad of PH's, I still have the stock mullard's and some SED's I'd got, and the place I got those SED tubes are selling Mullard XF4 single getters, but apparently double getters are supposed to be better, so does anyone know what the differences are between the two.
 
 
 
 
There's been quite a bit written about the reliability of the PH's Earspeakers.
 
 
When I first got the BHSE, the tubes that came with it were the stock mullard's, however because I wasn't happy with how some songs sounded with my 009 / BHSE using those stock tubes, after about 5 months I change them to SED tubes.
Those songs did sound slightly better from using the SED's but I still wasn't completely happy, it was then I got the PH's.
 
Before getting the PH's I'd been using the SED's for over a year and they were still going strong, in fact I've heard the 007's with my BHSE while using the SED's and those songs I had problems with from the 009's, sounded very good with the 007's.
 
With me still having both the stock mullard's and SED's, I might end up getting a pair of 007's.
 
P.S. I did have the 007mk1's for 11 years which were being driven by the SRM-007t, but because I was so disappointed with how the mk1's sounded with that amp, I used them both as part exchange for the source I have.
 
 
 
 
The silver paint [ if that's what it is ] at the top of the PH tubes Justin, had faded to virtually see through, so there's noway I'll be using that first quad again, however how is testing tubes spec done ?

David, you can go to this website to see all the different variations of NOS EL34 tubes - http://www.tube-classics.de/TC/Tubes/Valvo%20EL34/EL34.htm
 
Basically, the earlier the date, the better sounding the tube is.
 
The tubes we're talking about (DD getters), were manufactured between 1957-1962.
 
The tubes you're looking at are manufactured between 1976-1980.

 

[georgep]

David, you can go to this website to see all the different variations of NOS EL34 tubes - http://www.tube-classics.de/TC/Tubes/Valvo%20EL34/EL34.htm

Basically, the earlier the date, the better sounding the tube is.

The tubes we're talking about (DD getters), were manufactured between 1957-1962.

The tubes you're looking at are manufactured between 1976-1980.

That site claims the el61 is the same as el34, but it is not. Use it in your bhse at your peril. The el60, however, is the same, just a different pin out.

 

[georgep]

I see now, they sell tubes as well...

 

[Earspeakers]

 
If memory serves me correctly, the EL34's in the BHSE are run with standing plate currents in the 20mA range. This is barely breathing for an EL34. Good ones should last 25 years or more at this rate ... The problem here is the inconsistent quality control of  new production tubes.

 
Here's the definitive answer. 
 
Which brings up the question then, of the new production which is the most reliable? Maybe been discussed before but perhaps worth bringing up again. 

 

[David1961]

David, you can go to this website to see all the different variations of NOS EL34 tubes - http://www.tube-classics.de/TC/Tubes/Valvo%20EL34/EL34.htm

Basically, the earlier the date, the better sounding the tube is.

The tubes we're talking about (DD getters), were manufactured between 1957-1962.

The tubes you're looking at are manufactured between 1976-1980.

Thank you Ed, however because of the reliability of the place I got the SED's from, I think I'll get a quad of the Mullard EL34 XF4's from there, they are also the industrial version.

I've read that the XF1's and XF2's were better made than the later ones, but industrial stuff is also well made,

 

[Golfnutz]

That site claims the el61 is the same as el34, but it is not. Use it in your bhse at your peril. The el60, however, is the same, just a different pin out.

EL60 is the only one other than the EL34 he has listed in the photos. He mentions the EL61 as part of the evolution of the EL34.
 
It's still a good suggestion on your part, that the only tubes that should be used are the EL60 (w/adapter), and EL34.
 
I know you've also mentioned before that even the 6CA7 can have different variations, and caution should be used when selecting those tubes as well.

 

[georgep]

EL60 is the only one other than the EL34 he has listed in the photos. He mentions the EL61 as part of the evolution of the EL34.

It's still a good suggestion on your part, that the only tubes that should be used are the EL60 (w/adapter), and EL34.

I know you've also mentioned before that even the 6CA7 can have different variations, and caution should be used when selecting those tubes as well.

In the write up above he/she actually claims the el61 along with the el60 have the same characteristics as the el34.

 

[georgep]

Thank you Ed, however because of the reliability of the place I got the SED's from, I think I'll get a quad of the Mullard EL34 XF4's from there, they are also the industrial version.

I've read that the XF1's and XF2's were better made than the later ones, but industrial stuff is also well made,

Would like to hear more about this "industrial" version. Never heard of such a distinction with el34 before.

 

[Golfnutz]

Thank you Ed, however because of the reliability of the place I got the SED's from, I think I'll get a quad of the Mullard EL34 XF4's from there, they are also the industrial version.

I've read that the XF1's and XF2's were better made than the later ones, but industrial stuff is also well made,

No worries David, I was just pointing out the differences as it can be confusing (XF4 DD getters vs XF4 O getter).

 

[Golfnutz]

In the write up above he/she actually claims the el61 along with the el60 have the same characteristics as the el34.

Then you'll have to ask him what he means by characteristics...
 
As I mentioned, he only shows a photo of the EL60, nothing about EL61. I would assume if the EL61 was an equivalent it would have been included.

 

[georgep]

The picture is actually of an el34 that was a factory modified el60 - they are very rare. So technically that is not a picture of an el60.

And by characteristics, I would suspect this seller would suggest that all the earlier iterations are the same from a technical perspective other than the different base. Seen these eBay sellers doing this routinely.