Hi,
LOL. Let me know what it looks like.
As for gain, it's going to be tricky if you want to stick to two stages but doable, me thinks.
Does this new baby have a name yet?
Ciao, 😉
LOL. Let me know what it looks like.
As for gain, it's going to be tricky if you want to stick to two stages but doable, me thinks.
Does this new baby have a name yet?
Ciao, 😉
Hi Kevin,
I have some Siemens ECC84 and PCC84. Perhaps I should send a few to you for comparison. Do you have a preference for ECC or PCC?
I actually also considered using it as a cascoded frontend, as you are doing, but never got around using them.
Mogens
I have some Siemens ECC84 and PCC84. Perhaps I should send a few to you for comparison. Do you have a preference for ECC or PCC?
I actually also considered using it as a cascoded frontend, as you are doing, but never got around using them.
Mogens
Hi,
@Mogens: Can you tell me if these ECC84s have a frame grid type construction like the ECC88?
TIA, 😉
@Mogens: Can you tell me if these ECC84s have a frame grid type construction like the ECC88?
TIA, 😉
Hi Frank,
First, I have to make a correction. I got the box out and my xCC84 is Philips, not Siemens.
Can I see tell if it's a frame grid type without taking it apart? Visually there are many similarities with a ECC88.
Mogens
First, I have to make a correction. I got the box out and my xCC84 is Philips, not Siemens.
Can I see tell if it's a frame grid type without taking it apart? Visually there are many similarities with a ECC88.
Mogens
Hi,
From what I found on the web it looks more like those small plate ECC81s RFT in East-Germany used to make.
Does it look like this one:
ECC 84, Tube ECC84; Röhre ECC 84 ID2758, Double Triode
If so that kind of construction is called a folded anode construction (pancake style).
I was hoping for a frame grid style as these are often the lowest noise triodes.
Thanks anyway, 😉 (Tak?)
From what I found on the web it looks more like those small plate ECC81s RFT in East-Germany used to make.
Does it look like this one:
ECC 84, Tube ECC84; Röhre ECC 84 ID2758, Double Triode
If so that kind of construction is called a folded anode construction (pancake style).
I was hoping for a frame grid style as these are often the lowest noise triodes.
Thanks anyway, 😉 (Tak?)
Hi Frank,
I have a little difficulty in judging from the picture on that link. I have found another one here:
ECC84 @ The National Valve Museum
I don't think it's a frame grid type.
Mogens
I have a little difficulty in judging from the picture on that link. I have found another one here:
ECC84 @ The National Valve Museum
I don't think it's a frame grid type.
Mogens
Hi Frank,
Interesting you mention the ECC81 as the 6N14P plate structure looks a lot like those, and these do not appear to use a frame grid..
Overall they appear to be very nicely made.
MKC, A comparison with the ECC84 could be quite interesting - for what it's worth the 6CW7/ECC84 is not a tube I have ever run across - I don't think it was too widely adopted over here. In addition I have noticed some minor parametric differences between different ECC84s listed at frank.pocnet.net When I was a kid I recall we had an inexpensive Japanese made FM radio at our vacation cottage (American dacha lol) that I think used a 6CW7 in the FM front end, and we could not get a replacement for it.
Interesting you mention the ECC81 as the 6N14P plate structure looks a lot like those, and these do not appear to use a frame grid..
Overall they appear to be very nicely made.
MKC, A comparison with the ECC84 could be quite interesting - for what it's worth the 6CW7/ECC84 is not a tube I have ever run across - I don't think it was too widely adopted over here. In addition I have noticed some minor parametric differences between different ECC84s listed at frank.pocnet.net When I was a kid I recall we had an inexpensive Japanese made FM radio at our vacation cottage (American dacha lol) that I think used a 6CW7 in the FM front end, and we could not get a replacement for it.
Hi,
Back in the early Nineties when I was dealing with a lot of tube stock I had probably a few hundred boxes full of ECC84s.
None of them were of any reputable manufacturer, mainly rebranded god knows what, and we didn't know what to do with them.
No one, and I mean no one, ever asked me if I had ECC84s. Not in the fifteen years I dealt tubes all over the globe.
Who uses ECC85s nowadays? Same story.
And that was a tube you'd find in almost any old Philips radio set from back in the Seventies
But you know how it goes; in those days we wanted Philips, RCA, Telefunken, Mullard etc. Anything from the other side of the Iron Curtain?
Nobody wanted to be seen with it. It was as if you had the plague if you had a Melodya LP in your collection.
Mind you some of that stuff was quite good but there was a lot of junk too mostly because they didn't have the means to do a proper production recording.
I sill recall it as if it was yesterday when I had the first USSR tube in my hands shortly of the fall of the Berlin Wall. It felt strange. As if somehow that little tube had landed from Mars.
And you still wouldn't believe it was any good.
That's how we were brought up. Don't trust anything from that part of the world. Political propaganda really.
Still, it was fascinating though.
The difference between those tubes and a European or U.S. made one was as night and day as comparing the cockpit of a Boeing 747 with one of a Tupolev airliner.
The mighty Jumbo had nice elegant switches and knobs whereas the Tupolev sported the same style of clunky switches from fifteen years earlier. You know, the ones that you flipped with the side of your palm, not your finger tip.
Still, I can't recall there ever having been a technical delay for any of these Russian aircraft. Not that they'd tell us but still.
Oh, and their freighter aircraft. The one with these huge, huge hanging wings. Wow...
Ironically, while googling late this afternoon for the ECC84 I found much more Japanese diagrams using it in all sorts of amps than anything else. Driver stages, SRPP (of course) and what have you.
Can't say I've ever seen a European or American amp using it though....
It's often as if they know more about our tubes then we do.
So, shall we say this was the official kick-off for the new Musvovite then?
Ciao, 😉
Back in the early Nineties when I was dealing with a lot of tube stock I had probably a few hundred boxes full of ECC84s.
None of them were of any reputable manufacturer, mainly rebranded god knows what, and we didn't know what to do with them.
No one, and I mean no one, ever asked me if I had ECC84s. Not in the fifteen years I dealt tubes all over the globe.
Who uses ECC85s nowadays? Same story.
And that was a tube you'd find in almost any old Philips radio set from back in the Seventies
But you know how it goes; in those days we wanted Philips, RCA, Telefunken, Mullard etc. Anything from the other side of the Iron Curtain?
Nobody wanted to be seen with it. It was as if you had the plague if you had a Melodya LP in your collection.
Mind you some of that stuff was quite good but there was a lot of junk too mostly because they didn't have the means to do a proper production recording.
I sill recall it as if it was yesterday when I had the first USSR tube in my hands shortly of the fall of the Berlin Wall. It felt strange. As if somehow that little tube had landed from Mars.
And you still wouldn't believe it was any good.
That's how we were brought up. Don't trust anything from that part of the world. Political propaganda really.
Still, it was fascinating though.
The difference between those tubes and a European or U.S. made one was as night and day as comparing the cockpit of a Boeing 747 with one of a Tupolev airliner.
The mighty Jumbo had nice elegant switches and knobs whereas the Tupolev sported the same style of clunky switches from fifteen years earlier. You know, the ones that you flipped with the side of your palm, not your finger tip.
Still, I can't recall there ever having been a technical delay for any of these Russian aircraft. Not that they'd tell us but still.
Oh, and their freighter aircraft. The one with these huge, huge hanging wings. Wow...
Ironically, while googling late this afternoon for the ECC84 I found much more Japanese diagrams using it in all sorts of amps than anything else. Driver stages, SRPP (of course) and what have you.
Can't say I've ever seen a European or American amp using it though....
It's often as if they know more about our tubes then we do.
So, shall we say this was the official kick-off for the new Musvovite then?
Ciao, 😉
Probably the kick off for another Muscovite, this will be the third design in the series.. I think I will call it the Muscovite Medea.. 😀
My interest in Russian tubes goes back to a fundamental curiosity about our then adversary which started with a Russian trade show I visited in Boston when I was ten. Later when I was attending high school in Brussels I actually went there.. Quite an eye opener.
My interest in Russian tubes goes back to a fundamental curiosity about our then adversary which started with a Russian trade show I visited in Boston when I was ten. Later when I was attending high school in Brussels I actually went there.. Quite an eye opener.
Hi Kevin,
Well, I will send you a few ECC84 or PCC84 for investigation purpose. I know you have a uTracer. Would you like 4 of one type or 2 pieces of ECC84 and 2 PCC84?
Please PM your address. Also, please have a little patient as my day job don't allow me easy access to the post office. I might not get them shipped before end of next week.
I have always thought of the ECC84 as an ECC88 with half the gm. But, I have actually never had any of them wired up. This might be a good reason to try it out.
Mogens
Well, I will send you a few ECC84 or PCC84 for investigation purpose. I know you have a uTracer. Would you like 4 of one type or 2 pieces of ECC84 and 2 PCC84?
Please PM your address. Also, please have a little patient as my day job don't allow me easy access to the post office. I might not get them shipped before end of next week.
I have always thought of the ECC84 as an ECC88 with half the gm. But, I have actually never had any of them wired up. This might be a good reason to try it out.
Mogens
Yet Another Screen Capacitor Update!
The K71-4 1uF polystyrene film and foils arrived from Ukraine today, and I installed them in parallel with the existing 4.7uF Erse Pulse X having removed the 1uF Erse.
I should probably add a small series resistance, but my initial impression is that the pre-amp is much brighter, quicker sounding and the HF detail is markedly better. There is a lot more air (or is that HF tracing distortion?
No, not really) which is welcome, along with a slight steeliness that is not so much..
It's actually a pretty big improvement in most respects, we will see how things sound when the pre and the rest of the system is fully warmed up in a couple of hours.
Lot of capacitor bang for the buck..
The K71-4 1uF polystyrene film and foils arrived from Ukraine today, and I installed them in parallel with the existing 4.7uF Erse Pulse X having removed the 1uF Erse.
I should probably add a small series resistance, but my initial impression is that the pre-amp is much brighter, quicker sounding and the HF detail is markedly better. There is a lot more air (or is that HF tracing distortion?
No, not really) which is welcome, along with a slight steeliness that is not so much..It's actually a pretty big improvement in most respects, we will see how things sound when the pre and the rest of the system is fully warmed up in a couple of hours.
Lot of capacitor bang for the buck..
It's a pity the larger values are not easily available. Oleg(Alexer1) used to have 10uF but that was quite a while ago and as far as I know they are only 160v rating-although that probably isn't a problem as these Soviet mil spec caps seem to be extremely conservatively rated.
I don't see any of the 10uf ones now; you have to be quick!! I also recommend the (polyester) k73-16 if you need large values but don't have the space to go crazy. I use 22uf for phantom voltage blocking in most of my mic amps. They don't have the negative impact on the sound that I associate with most polyester caps. They have the usual military rhombus and I would assume the actual physical construction is first rate.
6N14P
I am listening to my latest phono stage design with a 6N14P cascode front end and am pleased by what I am hearing.
Gain I estimate is 10dB lower due to the much lower transconductance of the 6N14P as compared to the 6J9P. The 6J9P has about 3x higher transconductance at 10mA as the 6N14P..
I will start a new thread once I get things a little more sussed out. Look for Muscovite Mini II..
I am listening to my latest phono stage design with a 6N14P cascode front end and am pleased by what I am hearing.
Gain I estimate is 10dB lower due to the much lower transconductance of the 6N14P as compared to the 6J9P. The 6J9P has about 3x higher transconductance at 10mA as the 6N14P..
I will start a new thread once I get things a little more sussed out. Look for Muscovite Mini II..
It's about as quiet as the 6J9P version, it sounds quieter. I am still plagued by measurement system low frequency noise issues but 1/f noise worst case was perhaps -75dBr relative to a 1kHz fundamental at roughly 5mVrms, it might be better than this as I was primarily interested in tweaking the RIAA response.
I will say this is a singularly unfussy tube, I was able avoid all of the stability fixes I used in the 6J9P based version. Believe it or not curiosity got the better of me, and using the data sheet curves I designed the front end without spice or any tube models. I have yet to trace a few samples and generate a model.
I will say this is a singularly unfussy tube, I was able avoid all of the stability fixes I used in the 6J9P based version. Believe it or not curiosity got the better of me, and using the data sheet curves I designed the front end without spice or any tube models. I have yet to trace a few samples and generate a model.
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