bear said:Newcomers to the thread, it may be useful to wade through at least the first 50% (or more, if it grabs you) and spend an hour or so to see what has come before. Suggested schematics have been posted. You will have to draw your own conclusions. If you are looking for a quick DIY copy plan, it's not here. Some of the subtleties of the actual circuit have not been specifically shown by Mr. Curl... FYI, and fwiw.
Aptly said! Some valuable diamonds are there for those willing to mine the thread. I have completely changed my approach to power supply regulation, and have a much better feel or the fundamental behaviour of feedback as a result of lurking in the background of this thread.
I'm not saying that Mr. Curl has the only perfect approach to every issue, but for his knowledge and years of experience, he certainly has valuable insights that we get to learn from without the effort of the experimentation, trial and error.
Second, Mr. Curls presence in this thread has attracted others of substantial knowledge, talent and experience into providing their insights. Intentional or otherwise, he created an "audiophile designer collective" of sorts from which we have benefited.
Lastly, some here find Mr. Curl's interactions to be excessively abrasive, but you can't argue that his personality hasn't catalyzed some of the most enlightening debates between experts from widely varying electronics backgrounds. If everyone here simply nodded and said "Yes, of course Mr. Curl!" we would have missed out on a great deal. Although at times Mr. Curl may wish there were a rule saying you can't question his views, I suspect that despite his simetimes gruff complaints even he gets significant stimulation from the debates and discussions.
The only part of this thread that annoys me is when people blindly throw rocks at others so that they can delude themselves into the belief that they are better than their targets.
Terry
P.S. Personally, I hope that Mr. Curl gets surrounded soley by yes-men at that other place so that he'll get bored and come back here!
Edmond Stuart said:'A picture (i.e. a schematic) is worth a thousand words'.
Edmond
I think it’s unfair to ask for the schematics. Please remember that JC is still making amps and is using “some” of the ideas from the BT in his newer designs. It’s his living.
This is a DIY forum, OK, but not everybody in here is DIY people.
BTW: this thread is no longer about the BT, its more like a discussion thread, and I personally like the inputs by you Edmond, Scott, syn08, Wavebourn, Janneman, bear, SY, and John. (Sorry if I forgot somebody).
JC will soon be back and I’m sure that he has some comments on last week’s discussion.
To metalman: a very good post and of cours I agree.
Cheers
Re: Re: Re: Re: Re: Re: ... turkey for dinner?
You can easilly eliminate that by using JFets, then you can start to worry about wire. 😀
Trevor White said:I'd be more concerned about the effects of a PN junction before I would be of a bit of wire 😉
You can easilly eliminate that by using JFets, then you can start to worry about wire. 😀
C2H5OH
Jan, I did just that by visiting Hoppe (my local pub). 😉 As for medicines, it's a far better place than this one.
janneman said:Edmond, isn't it time for your daily medicine? 😉
Jan Didden
Jan, I did just that by visiting Hoppe (my local pub). 😉 As for medicines, it's a far better place than this one.

Re: Re: Re: Re: Re: Re: Re: ... turkey for dinner?
...Eliminating that by JFets you start to worry about their wide spread of parameters, non-linear capacitances, gate currents and their noises, dependencies of transconductances on voltages and currents, and so on... 😉
So, when somebody starts using "no compromise" word I think that the person is either ignorant, or plays the role in front of audioreview cameras. 😀
Andre Visser said:
You can easilly eliminate that by using JFets, then you can start to worry about wire. 😀
...Eliminating that by JFets you start to worry about their wide spread of parameters, non-linear capacitances, gate currents and their noises, dependencies of transconductances on voltages and currents, and so on... 😉
So, when somebody starts using "no compromise" word I think that the person is either ignorant, or plays the role in front of audioreview cameras. 😀
Re: C2H5OH
Let me suggest you Edmond the best medicine place:
Edmond Stuart said:
Jan, I did just that by visiting Hoppe (my local pub). 😉 As for medicines, it's a far better place than this one.![]()
Let me suggest you Edmond the best medicine place:

Re: Re: C2H5OH
Janneman and the food is
Elektor
Wavebourn said:
Let me suggest you Edmond the best medicine place:
![]()
Janneman and the food is
Elektor
pyrates?
Hi Stinius,
Actually, I didn't ask for schematics (and I don't need them as well). I only said/meant that (for some people) it's more revealing than a thousands words.
Nevertheless, I fully agree with this comment from Anatoliy.
Cheers,
Edmond.
stinius said:Edmond
I think it’s unfair to ask for the schematics. Please remember that JC is still making amps and is using “some” of the ideas from the BT in his newer designs. It’s his living.
[snip]
Cheers
Hi Stinius,
Actually, I didn't ask for schematics (and I don't need them as well). I only said/meant that (for some people) it's more revealing than a thousands words.
Nevertheless, I fully agree with this comment from Anatoliy.
Cheers,
Edmond.
Re: pyrates?
Hi Edmond
Then we agree 😉
Cheers
Edmond Stuart said:
Hi Stinius,
Actually, I didn't ask for schematics (and I don't need them as well). I only said/meant that (for some people) it's more revealing than a thousands words.
Nevertheless, I fully agree with this comment from Anatoliy.
Cheers,
Edmond.
Hi Edmond
Then we agree 😉
Cheers
Those, who followed this thread patiently, would be able to make almost exact copy. For those who did not any hint was useless.
LSD
That's far more than "a few 100 ugrams of ........" 😀
Wavebourn said:...and some medicine pills. Headache pills, I suppose. 😎
![]()
That's far more than "a few 100 ugrams of ........" 😀
Re: LSD
Are you coming this year?
You may have a chance to meet JC in person and tell him everything you think about. 😉
Edmond Stuart said:
That's far more than "a few 100 ugrams of ........" 😀
Are you coming this year?
You may have a chance to meet JC in person and tell him everything you think about. 😉
I can't imagine any good reason why one should even attempt to duplicate the BT preamp, even if the official schematics would be publicly available.
- Status
- Not open for further replies.
- Home
- Amplifiers
- Solid State
- John Curl's Blowtorch preamplifier