Luminaria with Iron amp two interesting diy projects from Mr Rothacher.
I wait to
Attachments
So.... here it is
The April 2014 Issue of audioXpress is Now Online | audioXpress
For those interested in DIY projects, you will enjoy a great concept from Michael Rothacher with his LuminAria: A SIT Preamplifier. The author intended this preamplifier to be “compact enough to fit in a suitcase” and a “good-sounding, unusual preamplifier with a spiffy set of performance specifications.” He completed the project in two months, and it was one of the highlights at the Burning Amp Festival in San Francisco.
Anyone have read it ?
The April 2014 Issue of audioXpress is Now Online | audioXpress
For those interested in DIY projects, you will enjoy a great concept from Michael Rothacher with his LuminAria: A SIT Preamplifier. The author intended this preamplifier to be “compact enough to fit in a suitcase” and a “good-sounding, unusual preamplifier with a spiffy set of performance specifications.” He completed the project in two months, and it was one of the highlights at the Burning Amp Festival in San Francisco.
Anyone have read it ?
Hi Tea-Bag
Could you share more information about topology ,what sit is used in this preamp?
Thanks
Best regards
I think it's Mr. Rothacher decision on what one can share from this document.
Not too much, since it's a published item, I don't want to have any copyright issues.
So I will be vague...
The Sit part is an expected and available part. Lets start with that.
He runs the voltage pretty high.
He provides solution for input/output impedance.
It's got lots of math in it! He does state it's not a beginners project and I would concur.
Not too much, since it's a published item, I don't want to have any copyright issues.
So I will be vague...
The Sit part is an expected and available part. Lets start with that.
He runs the voltage pretty high.
He provides solution for input/output impedance.
It's got lots of math in it! He does state it's not a beginners project and I would concur.
I think I can share a little bit without stepping on any toes.
LumnAria was a little demo project I did for my 2012 trip to Burning Amp. It uses the 2SK82 KD-33, specifically, which I’m told is no longer available. I tried as much as possible to start with a set of design goals and design constraints, and then show my rationale for various design decisions, including the math, as there always seems to be some interest in how things can be calculated.
It is probably more of a proof-of-concept/learning piece than a straight-up project piece, so I leave it to you to decide if you’d like to buy a copy. Naturally, I encourage you to support audioXpress and I'm grateful for your interest.
LumnAria was a little demo project I did for my 2012 trip to Burning Amp. It uses the 2SK82 KD-33, specifically, which I’m told is no longer available. I tried as much as possible to start with a set of design goals and design constraints, and then show my rationale for various design decisions, including the math, as there always seems to be some interest in how things can be calculated.
It is probably more of a proof-of-concept/learning piece than a straight-up project piece, so I leave it to you to decide if you’d like to buy a copy. Naturally, I encourage you to support audioXpress and I'm grateful for your interest.
Attachments
Nice to have some informative advert.
Thanks Mike
link for buy on line is :
audioXpress Issue April 2014
Greetings
Thanks Mike
link for buy on line is :
audioXpress Issue April 2014
Greetings
Yes, thank you. It should be .25W (1/4W) not 25W. Oops
I'm glad you enjoyed it.
I just wanted to order all 25W resistors when I looked at the picture and hesitated….
Your article is so patient with us and you really care for the stuff and us…
THX
O.k. Mike I will build it point to point.
Unfortunately I have only KE at the moment.
I did some measurements with the SITs some time ago with lockys curve tracer. The data are not very reliable, because the negative gate voltage is subtracted from the available drain voltage (24V). So there is not much headroom and weird effects in the graphs when the PSU collapses.
Nevertheless I have the impression that the KE in red (KD in black) reach the wanted drain current at lower negative gate voltages than the KD.
So I will simply try to get the 90V and 50mA with the KE and then look at the distortion when I change the R112 (600R) pot.
The green one is a KF
o.k.?
Unfortunately I have only KE at the moment.
I did some measurements with the SITs some time ago with lockys curve tracer. The data are not very reliable, because the negative gate voltage is subtracted from the available drain voltage (24V). So there is not much headroom and weird effects in the graphs when the PSU collapses.
Nevertheless I have the impression that the KE in red (KD in black) reach the wanted drain current at lower negative gate voltages than the KD.
So I will simply try to get the 90V and 50mA with the KE and then look at the distortion when I change the R112 (600R) pot.
The green one is a KF
o.k.?
