My idea from technics is that they adjust the bias actively based on the sound level..
SE-A1, constant quiescent current level (7A), floating rail potential
(diy design : Elektor A+B, '79 Januari issue)
For a hybrid A-D implementation, see Figure 8 of the '78 patent for the Technics SE-A1, US4115739
Thanks for the patent information from technics. It is very much the same technology. Difference is that because I do it digital I can apply voltage just before the sound arrives, and remove it some time after the audio has gone. This reduces distortion and improves damping a little, but the principles are exactly the same, reduce voltage to reduce dissipation doing it by a switching amplifier that feeds a class a amplifier.
Last edited:
Yes it's SARA . And new pictures ....
Best regards,Alex
Hi Alex,
Is it based on your own design? I searched the web for Sara amplifier and found some posts for 2014 but at the time, the amplifier was able to drive 8 ohms load and down to 6 ohms but can it now support 4 ohms load and maybe a little lower?
Thanks
Do
Noritake GU3900 vfd as display
beautiful, but oh so pricey
beautiful, but oh so pricey
I got it with 50% discount, but still...
Yes, there is no problems with 4ohm loads and it can drive and 2ohm loads for a resonably time.Hi Alex,
Is it based on your own design? I searched the web for Sara amplifier and found some posts for 2014 but at the time, the amplifier was able to drive 8 ohms load and down to 6 ohms but can it now support 4 ohms load and maybe a little lower?
Thanks
Do
it can drive 2ohm loads for a reasonable time.
(one look at the output device package type tells me that isn't true)
Better looking on the motherboard . You will see the recomended transistors. The power supply voltage is +50v/-50v. "Resonably time" mean that time when the amplifier have a real loudspeakers at the binding post with 2ohm impedance in the narrow band on the real music.
For 8ohm and 4ohm can be a resistive load on a sinusoidal signal test.
For 8ohm and 4ohm can be a resistive load on a sinusoidal signal test.
see the recomended transistors.
What I see is TO-3P output devices.
3 pairs of those are of significance for 8 and 4 ohm loads.
For 2 ohm, they're not even the equivalent of 2 pairs of TO-264's
(maybe your definition of the narrow band on real music is limited to tweeters)
What I see is TO-3P output devices.
3 pairs of those are of significance for 8 and 4 ohm loads.
For 2 ohm, they're not even the equivalent of 2 pairs of TO-264's
(maybe your definition of the narrow band on real music is limited to tweeters)
No. You see only what you want to see. If u are looking at the empty board, without final transistors , you will see the recomended transistors. There are MJL4281 and MJL4302. That It is clearly visible.
Alexmm put the STA1962 instead of MJL4302 because his speakers there ar not representing a heavy load and the Ccbo of the final transistor it is much smaller.
Narrow band of the impedance of the loadspeaker versus frequency. I did not see speakers with 2ohm on a wide band of frequency. The same thing for a combination of a resistive and phase component which equates a pure resistive 2ohm load current.
I've never tried his toroidals, only his small R-core xformers that all worked as expected. Since you're in NYC, I've had great experience with Antek in NJ. Right across the river. If what you need is in stock, I think the prices are fair. They are well-made too, and shipping is flat USPS Priority postage.
Rick
Welll Maybe.. just received a 400 va one.
Egg shaped
Not pleased.
Email response ? Zero.
Pictures of my Lynx amp
Here are some pictures of my Lynx amps
Here are some pictures of my Lynx amps
Attachments
Last edited:
...not ready yet....
8 month working(designing constructing and relaxing!)
8 month working(designing constructing and relaxing!)
Attachments
-
DSC03485.JPG217.9 KB · Views: 556
-
DSC03482.JPG234.7 KB · Views: 526
-
DSC03478.JPG208.4 KB · Views: 486
-
DSC03466.JPG192.4 KB · Views: 551
-
DSC03444.JPG223.4 KB · Views: 601
-
DSC03442.JPG219.2 KB · Views: 541
-
DSC03440.JPG211.5 KB · Views: 711
-
DSC03437.JPG255.1 KB · Views: 734
-
DSC03473.JPG191.6 KB · Views: 472
-
DSC03430.JPG302.7 KB · Views: 617
- Home
- Amplifiers
- Solid State
- Post your Solid State pics here