Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 Solid State Talk all about solid state amplification.

 Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
 Yesterday, 05:31 PM #2701 gaborbela   diyAudio Member   Join Date: Sep 2005 With the 22V transformer, you get 26.4V plus U use CRCRCRC power supply. With the 3pc R you burn up some power also. I hope you not using any high-value resistors there to burn up more power. Your 25.6V is absolutely normal with your setup. When you buy a transformer to regular Class A bias calculation(not talking about Alep X where the total bias is over 7A per channel) 22ACV x 1.2 under load =26.4V DC.
 Yesterday, 05:56 PM #2702 tonza75   diyAudio Member   Join Date: Jan 2010 I think you know better and waiting for someone to answer.
 Yesterday, 07:13 PM #2703 Juntuin   diyAudio Member   Join Date: Aug 2015 Location: Finland B.B. one channel: 39,7vdc under load. 2x30vac sec 545va trafo. Can't remember or measure Alpha20 right now..
xrk971
Got Foam?
diyAudio Member

Join Date: Oct 2012
Location: Metro DC area
Quote:
 Originally Posted by gaborbela With the 22V transformer, you get 26.4V plus U use CRCRCRC power supply. With the 3pc R you burn up some power also. I hope you not using any high-value resistors there to burn up more power. Your 25.6V is absolutely normal with your setup. When you buy a transformer to regular Class A bias calculation(not talking about Alep X where the total bias is over 7A per channel) 22ACV x 1.2 under load =26.4V DC.
I am using 0.15R - ok so normal. My problem is that I have been using 1.4x and subtracting 3-4v for load. But 1.2x multiplier seems way to go for Class A. My CRCRCRC burns off 1.2v.
__________________
XRKaudio https://www.etsy.com/shop/XRKAudio

Juntuin
diyAudio Member

Join Date: Aug 2015
Location: Finland
Quote:
 Originally Posted by Juntuin B.B. one channel: 39,7vdc under load. 2x30vac sec 545va trafo. Can't remember or measure Alpha20 right now..
Oh, forgot that CCRCCRC where 0.2ohm per resistor.

fab
diyAudio Member

Join Date: Mar 2004
Quote:
 Originally Posted by xrk971 ?... I recently bought a pair of 22VAC 300VA Anteks, hoping to get a solid 27vdc under load of 1.6amps. After the CRCRCRC, I am getting 25.6v. This is for a high output variant of the Alpha 20 that I am testing - just seeing if pushing higher voltage and increased cooling via CPU coolers and fans can work to boost power output.
Hi X
Antek supplier specifies output voltage under specific load current (not much data though) with 120vac input. In my area line voltage from provider can vary from 115 to 122vac (I have a real time indicator) in normal situation (not too cold/hot weather). Mostly depends on time of the day with demands from all houses/buildings.
Also, rectifier diodes have different voltage drop depending on their temperature. Check the specific data sheet of your diodes.
And then you add the voltage drop of the resistors in series in your PSU.
Fab

 Yesterday, 10:32 PM #2707 Vunce   diyAudio Member   Join Date: Jan 2014 With my 600va, 32v transformers, my BB’s are running at 37.5vdc with a CRCLC. If I use a capMx instead of the CRCLC the voltage increases to 38vdc. Since it’s summertime, my line voltage varies widely during a 24 hr period. Anywhere from 112vac to 125vac. I think my ALPHA20 is running 23vdc, I’d have to check (don’t remember). I did notice that the DC offset increased from 10mv @36vdc to 25mv @37.5vdc? Last edited by Vunce; Yesterday at 10:53 PM.
 Today, 01:31 AM #2708 xrk971   Got Foam? diyAudio Member     Join Date: Oct 2012 Location: Metro DC area Hi Vunce, You must have some big power with 37.5v rails. I am guessing upwards of 70w? You have these 99dB Klipsch speakers so would never know what 70w feels like on the B.B. __________________ XRKaudio https://www.etsy.com/shop/XRKAudio
Vunce
diyAudio Member

Join Date: Jan 2014
Quote:
 Originally Posted by xrk971 You have these 99dB Klipsch speakers so would never know what 70w feels like on the B.B.
Exactly X
My Forte’s play incredibly loud with the ALPHA20. The appeal about the BB is that I get to use a powerful Class A amp with much less efficient speakers that I have.

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Site     Site Announcements     Forum Problems Amplifiers     Solid State     Pass Labs     Tubes / Valves     Chip Amps     Class D     Power Supplies     Headphone Systems Source & Line     Analogue Source     Analog Line Level     Digital Source     Digital Line Level     PC Based Loudspeakers     Multi-Way     Full Range     Subwoofers     Planars & Exotics Live Sound     PA Systems     Instruments and Amps Design & Build     Parts     Equipment & Tools     Construction Tips     Software Tools General Interest     Car Audio     diyAudio.com Articles     Music     Everything Else Member Areas     Introductions     The Lounge     Clubs & Events     In Memoriam The Moving Image Commercial Sector     Swap Meet     Group Buys     The diyAudio Store     Vendor Forums         Vendor's Bazaar         Sonic Craft         Apex Jr         Audio Sector         Acoustic Fun         Chipamp         DIY HiFi Supply         Elekit         Elektor         Mains Cables R Us         Parts Connexion         Planet 10 hifi         Quanghao Audio Design         Siliconray Online Electronics Store         Tubelab     Manufacturers         AKSA         Audio Poutine         Musicaltech         Holton Precision Audio         CSS         Dx Classic Amplifiers         exaDevices         Feastrex         GedLee         Head 'n' HiFi - Walter         Heatsink USA         miniDSP         SITO Audio         Twin Audio         Twisted Pear         Wild Burro Audio

 Similar Threads Thread Thread Starter Forum Replies Last Post xrk971 Analog Line Level 715 17th July 2018 07:00 AM xrk971 Group Buys 399 26th June 2018 10:26 PM xrk971 Headphone Systems 40 12th June 2018 02:06 AM klykx Full Range 1 9th October 2006 03:22 PM Prune Pass Labs 20 11th March 2004 03:05 PM

 New To Site? Need Help?

All times are GMT. The time now is 06:04 AM.