You do sound angry. What's the deal? what I am saying is not supported by your commercial interest? First, let me say I like WE91. I have some WE310A, 328A that I plan on doing a project someday. Thus, I have interest in this thread.
I am thinking this is a thread of brainstorming a "modern" design of WE91. Wait! maybe this is another one of those thread that either you are god or everyone should shut up.
Further, I have seen CCS used on pentode. Even Gary himself posted a CCS pentode schematic on audioasylum (it was triode strapped I believe, and I will concede this point). This is kind of why I ask. To see what is good and bad about it. If you simply don't use, don't like, or don't know how to build or sell a good one, then it is none of my business either. And I have never profit even a penny off people that listen to music. Don't think you can say that
Now will you feel happy if I say you should connect a TVC to a WE91?
Konnichiwa,
I believe that Jeff referred to studying up on electronics as good advise.
And no, I'm not angry, I'm exasperated. Without understanding the first thing of how the circuit works (or what a CCS does) you want to "improve" something by throwing the latest fashion gizmo at it, in as many places as possible and you preferably want someone else to do your designwork and when you are being told "it won't work" you keep insisting "it must improve things". I find that exasperating.
Sayonara
PS, as I have no investment in either NOS 310A's nor in CCS nor anything of the like the use of a CCS or not means zip to me commercially. I use a CCS where apropriate and desirable, I don't where it's not.
agent.5 said:
I believe that Jeff referred to studying up on electronics as good advise.
And no, I'm not angry, I'm exasperated. Without understanding the first thing of how the circuit works (or what a CCS does) you want to "improve" something by throwing the latest fashion gizmo at it, in as many places as possible and you preferably want someone else to do your designwork and when you are being told "it won't work" you keep insisting "it must improve things". I find that exasperating.
Sayonara
PS, as I have no investment in either NOS 310A's nor in CCS nor anything of the like the use of a CCS or not means zip to me commercially. I use a CCS where apropriate and desirable, I don't where it's not.
Konnichiwa
Me too. And to make it usuable it was shunted by a resistor of comparably low value, effectively inactivating it.
If you use a CCS on a Pentode you must in effect deactivate it to make the circuit work. If you had botherd to study a little electronics, you would know that a pentode behaves in effect as a (imperfect) CCS, it's current modulated by the various grids.
Given that, if you load a Pentode with a CCS any signal output you would get would be related to the imperfections of the pentode and CCS (their deviation from being a perfect CCS) and thus highly non-linear.
There is nothing inherently good or bad about a CCS, it is a tool for design, used byb a competent designer where apropriate.
Hmmm. I have published circuits incorporating Valve/Fet Cascoded Current Sources a good while before Gary ever did. I have not much of an interest to sell anything, in case you have not noted.
Hmmm. I have on occasion sold Equipment I have build or Cables and such to people based on a sensible amount of money for the parts plus labour. I'm not rich from it yet. A friend has convinced me to start working on Audio as a Business, so far I'm still investing a lot of time and money to get things up and running and thus have not profited at all, net I'm probably down quite a bit. Yes, I do eventually expect a reasonable return and maybe being able to quit my dayjob, but I have not planned that for a good while to come.
And it may interest you that of the commercial products non will use 300B's, some will use Currnet Soures and few will bear much if any resemblance to what I do for DIY, simply because my "no compromise" designs do not lend themselves to commercial "for profit" exploitation in the High End Market.
Why should I? I happen to like TVC's and have had my hand in making them happen, but it matters zip to me and my pocket if you buy one or not. If you do and like the results, more power to you.
It also matters zip to me if you take a working circuit and make a mess out of it by ignorantly throwing Current Sources at it to "improve" it. I merely wanted to save you wasting some time, but if you want to waste it, be my guest.
Sayonara
agent.5 said:
Me too. And to make it usuable it was shunted by a resistor of comparably low value, effectively inactivating it.
If you use a CCS on a Pentode you must in effect deactivate it to make the circuit work. If you had botherd to study a little electronics, you would know that a pentode behaves in effect as a (imperfect) CCS, it's current modulated by the various grids.
Given that, if you load a Pentode with a CCS any signal output you would get would be related to the imperfections of the pentode and CCS (their deviation from being a perfect CCS) and thus highly non-linear.
agent.5 said:
There is nothing inherently good or bad about a CCS, it is a tool for design, used byb a competent designer where apropriate.
agent.5 said:
Hmmm. I have published circuits incorporating Valve/Fet Cascoded Current Sources a good while before Gary ever did. I have not much of an interest to sell anything, in case you have not noted.
agent.5 said:
Hmmm. I have on occasion sold Equipment I have build or Cables and such to people based on a sensible amount of money for the parts plus labour. I'm not rich from it yet. A friend has convinced me to start working on Audio as a Business, so far I'm still investing a lot of time and money to get things up and running and thus have not profited at all, net I'm probably down quite a bit. Yes, I do eventually expect a reasonable return and maybe being able to quit my dayjob, but I have not planned that for a good while to come.
And it may interest you that of the commercial products non will use 300B's, some will use Currnet Soures and few will bear much if any resemblance to what I do for DIY, simply because my "no compromise" designs do not lend themselves to commercial "for profit" exploitation in the High End Market.
agent.5 said:
Why should I? I happen to like TVC's and have had my hand in making them happen, but it matters zip to me and my pocket if you buy one or not. If you do and like the results, more power to you.
It also matters zip to me if you take a working circuit and make a mess out of it by ignorantly throwing Current Sources at it to "improve" it. I merely wanted to save you wasting some time, but if you want to waste it, be my guest.
Sayonara
Something to remember
A Horse designed by commitee will likely end up being a Zebera.
If you want to build a WE91 clone then the best thing to do is reverse engineer it.
Keep the goal in mind, if you don't keep that the focus, you may never get to where you wanted to go in the 1st place.
If we want to design the best modern 300B amp with a pentode driver, is it likely we will end up with a WE91?
A Horse designed by commitee will likely end up being a Zebera.
If you want to build a WE91 clone then the best thing to do is reverse engineer it.
Keep the goal in mind, if you don't keep that the focus, you may never get to where you wanted to go in the 1st place.
If we want to design the best modern 300B amp with a pentode driver, is it likely we will end up with a WE91?
I wanted to cover this in more detail. When I first read it, irresistible force vs. immovable object came to mind.
A triode with a constant current source has the gain increased to about Mu, and the output Z increased from about Rp/2 to Rp.
In other words, gain is increased, and the CCS has an infinite AC resistance.
A pentode has relatively high gain and Zout about equal to its plate resistor. In other words, the AC impedance of the tube in infinite.
If you CCS load a pentode, from this rough analysis, you would expect extremely high gain and "infinite" Zout. This follows from the fact that we determined that the Zout of both the CCS and Pentode were "infinite". In other words, the circuit would be stuck at on supply rail or the other at all times and couldn't drive any real load.
agent.5, none of this sounds particularly useful to linear analog circuits.
Cheers;
Doug
I am not trying to continue any argument, just trying to figure out what some people are doing with their WE310A. Any comment on what this nutcase is doing with his triode strapped WE310A driver stage? I just am interested in why he is doing it so I can either eliminate it from consideration, or maybe copy it. Yes it is technically not a WE91, but I don't particularly care about that either.
http://www10.big.or.jp/~dh/work/7906.html
http://www10.big.or.jp/~dh/work/7906.html
fdegrove said:Hi,
Which is something other SE builders could try as well once they fall out of love with the tons of second harmonics distortion from the beloved SE ampies....
If you don't mind, send me an e-mail through the forum.
Cheers,
Thanks Frank, I am about to go away for a couple of weeks; I will contact you when I return
Further up this thread, it was commented that the WE91 schematic I posted used 6C6 and not 310A's.
I was determined to find an original WE schematic with 310A's, and now I have.
It would appear that the WE91A used the 6C6 and the WE91B used the 310A.
Please check out these links>>>
http://www.ys-audio.com/wce/we91a.jpg
http://www.ys-audio.com/wce/we91b.jpg
I was determined to find an original WE schematic with 310A's, and now I have.
It would appear that the WE91A used the 6C6 and the WE91B used the 310A.
Please check out these links>>>
http://www.ys-audio.com/wce/we91a.jpg
http://www.ys-audio.com/wce/we91b.jpg
You can buy TFA 204s, which are supposed to be better modern transformers based on the Peerless transformers used in the WE91, for $250. Here is a quote from the Bottlehead site:
"Originally designed by Peerless as a replacement for the famous Western Electric A171A transformer used in the WE91 300B amp. The MagneQuest TFA-204 uses modern insulating materials which take the sweet sonics even beyond those of the original."
I use a pair of these in my SE EL34 amp and I certainly like the way they sound FWIW. They can be found here:
http://www.bottlehead.com/et/MQ/magnequest.htm
No I am not affiliated in any way with any manufacturer or anyone else except my wife and a few close friends and the idiots I work for.
"Originally designed by Peerless as a replacement for the famous Western Electric A171A transformer used in the WE91 300B amp. The MagneQuest TFA-204 uses modern insulating materials which take the sweet sonics even beyond those of the original."
I use a pair of these in my SE EL34 amp and I certainly like the way they sound FWIW. They can be found here:
http://www.bottlehead.com/et/MQ/magnequest.htm
No I am not affiliated in any way with any manufacturer or anyone else except my wife and a few close friends and the idiots I work for.
WE91 Progress report
I have now got most of my parts, I have bought the OPTX in the end from Sowter, as they were cheaper then Partridge and delivered within about three weeks of placing the order.
I would reccommend them to anyone; the service is second to none.
Mr. Brian Sowter answering all of my silly questions by email within a day of my sending them.
They are the SA08 but with two primary taps at 2K5 and 3K5.
BTW, the transformers are beautiful!!!!!
I have now got most of my parts, I have bought the OPTX in the end from Sowter, as they were cheaper then Partridge and delivered within about three weeks of placing the order.
I would reccommend them to anyone; the service is second to none.
Mr. Brian Sowter answering all of my silly questions by email within a day of my sending them.
They are the SA08 but with two primary taps at 2K5 and 3K5.
BTW, the transformers are beautiful!!!!!
Another WE91A Progress Report
Konnichiwa,
Long in the works, my 91 Monoblock pair is up and running.
I wrote a prety lengthy set of notes on what I did over at the Audio Asylum and local loonies seem alread geared up for a flamefest again....
Well, if anyone is interested, surf over....
Oh no - YAWE91B300BA (Yet Another WE 91B 300B Amplifier)
Sayonara
Konnichiwa,
Long in the works, my 91 Monoblock pair is up and running.
I wrote a prety lengthy set of notes on what I did over at the Audio Asylum and local loonies seem alread geared up for a flamefest again....
Well, if anyone is interested, surf over....
Oh no - YAWE91B300BA (Yet Another WE 91B 300B Amplifier)
Sayonara
The link is bad - the pictures have gone - yet another site that gets rot from image hosting heaven being over.
I would like to know where to find some original overview.
albert, working on the Hiraga version of the WE91. I have 6SJ7 and some 6C6's.
a great find in this article is this:
I did indeed find out this is true also of the 6SJ7: there was a small DC today on my cathode while only AC for the heater was on . . .
Last edited:
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