Next week I will receive 50 assembled VSSA PCB-s. First I have to send prepayed orders and than inform here about the amount of PCB-s still available for interested DIY-ers. So be around. 😉
That's vs. Simple unregulated double mono +-35V, 300VA, 60000uF per channel PSU. Both working, thanks! Although, with new smps supply only. Can't get one channel to work on my linear supply due to strange psu behaviour when a speaker is connected. Psu output voltage drifts to positive or neg rail deliberatly. Must be a psu channel fault.
No answer to my emails and PM, to you. And even previous calls in this topic. Any problem, Andrej ?
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For members interested in the two feedback caps AC behave. Done simulation before, but here is realtime measure of caps AC behave in feedback position. Maybe best to download picture to be able to study better (zoom in/out).
For Esperado: see lighblue line and please don't shoot me
, but maybe help suggestions to get it stable in higher band. Like motion feedback on speakers, i think it will form the sound envelope presented, but last is what i think now, realtime trials later has to confirm or shoot it down. Those two caps for lightblue plot was awfull expensive at RS, but Digikey has better cost.
Regards Ricky
For Esperado: see lighblue line and please don't shoot me
, but maybe help suggestions to get it stable in higher band. Like motion feedback on speakers, i think it will form the sound envelope presented, but last is what i think now, realtime trials later has to confirm or shoot it down. Those two caps for lightblue plot was awfull expensive at RS, but Digikey has better cost.Regards Ricky
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So BYRTT, have you powered up your VSSA yet? I was waiting for your comparison with regular PSU and SMPS, as well as your listening impressions. Just curious.
That is why I'm using unregulated SMPS. Regulation normally interfere with/to audio modulation, causing a mess.
Last mail from you is about the permission to use VSSA sch to your needs. Otherwise everything OK and you know I am your admirerer.
Next week I'll get the last portion of VSSA PCB-s and two are reserved for you.
I had send-you 1 PM and 2 or 3 mails, since this one. Please PM-me an address where i can write-you in a more secure way.
I was afraid to had wrote something witch had make-you crossed against me.
Contrary to you, with your impressive and beautiful designs, nothing to admire looking at me: Just an old fart. The few things i know is just the effect of time, curiosity and passion for music. Just i was lucky enough to had two paralleled careers, both as a sound engeneer and an audio designer. It gives a more 'global' and insecure way to look at the numerous evils waiting for us when we have this incredible claim to reproduce sound universe with dirty bits of string 🙂
I'm just curious to read your comments on your listening results. Why to shoot at somebody dreaming of perfection 🙂
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Sorry not yet, finally had all bits and pieces hardware by 09. this month, but have not had time, and time i've got i had spended on other audio topic where that impedance measure unit from post #2445 is running all time.
First tests will be with SMPS and all bits and pieces as suggested/recommended. After that other PSU's. Then stuff like post #2445for trying reach best as possible reproduction in setup.
Me too, nearly my thoughts in VSSA domain 24/7, but will NOT rush VSSA together and starting circuit smoke as a consequence of hurrying. Expect my first impression in not more than 10 days.
Andrej you expressed eayrlyer in thread you like to read about members audio activities, therefor i allows me to post little off topic sometimes. Else knock on the door and volume will decrease after a moment /immediately 
.
/immediately .Hello All,
I'm wondering about transformer's size : is 300VA enought with 2x25v at secondary (+/-35 after bridge rectifier) ? What is the amount of power I can expect from such a set up ? 50, 60W ?
I'm wondering about transformer's size : is 300VA enought with 2x25v at secondary (+/-35 after bridge rectifier) ? What is the amount of power I can expect from such a set up ? 50, 60W ?
Just ironic about the shooting, reality was that your knowledge about trouble with that cap size is true up against my dreaming. Look at phase plot for the cap at high end. Phase looks like falling as leaving audio band where my measure unit can't discover behavour anymore. If it's because it becomes an inductor there with increasing AC impedance it can't sit there alone without a clever helper network to amend misbehavour. I put this cap on hold untill later, just bought two with other bits and got positive over the AC plot, therefor post/sharing.
Had been digging to your earlyer suggested motional feedback (bought 42 inductors for trials) and that started something untill further unbeliveable in sound presentation in room. If the direction i am heading under these tests holds in the end, you are a real hero for my speakers
their owner and the way to have headphones/studio like sound in room. Discovered some days ago when hardworking speaker guys posted to this thread that you last month started thread about motional feedback and got mood spoiled by critical members. I am very sorry for this, but can say if any comfort, that if my experience in motional feedback holds the positive direction, i will post at that thread to support for your suggestions.I did do big mistake other day, i used to have two Sansui stereo amps to drive 2x10" SPH-250KE botton and 2x5" Alpair 10.2 for top all in sealed cabs, now have only one amp, but little luck because top is fullranger so present i run one box L/R. By zeal and not thinking i tried little MF network right at amp
, and now it needs repair 🙁. No output devices broken, but suspects the little feedforward circuit has lost a device, but have not had time to investigate. From that mistake, now MF networks are placed at speaker cable end with these amps. Amps are old and restored but fine specs like DC-300kHz with both VFB and feedforward.Because i have got used to bandwidth from DC and up, more and more learn to understand circuits (thanks everybody) and their sound, i think the importance of that feedback caps AC-outriggers behavior measured in post #2445, will get me investigate there later to push more correct audioband groupdelay and maybe musical performance.
Drunk NO, Dreamer 🙂
Yes, you just measure the wire's inductances.
I was talking about motional (and inductance) impedance *compensation*. The purpose is just to let the amp loaded with a near flat impedance, and, so, not to have to deal with frequency variable current/voltage ratios. It has an influence on the feedback phase near the resonance, and change the Thiele and Small parameters with benefits, of course.Had been digging to your earlyer suggested motional feedback (bought 42 inductors for trials) and that started something untill further unbeliveable in sound presentation in room. If the direction i am heading under these tests holds in the end, you are a real hero for my speakers
Sorry about your misadventure. We have a French proverb which says: "Who try nothing get nothing".
About your cap fear, you will make your mind with your ears. It depend so much of the speakers you'll use. (and of the records you play ;-)
Brytt,
I was the one who brought up Christophe's conjugate network thread and I wish that he would continue it. Perhaps he could do it as a blog and then you don't have as much of the negative comments from those who seem to have a specific answer in mind, no matter any evidence to the contrary. I think and understand that Christophe was correct in his assumptions and reasoning and there was more to go with that. How can you ever go wrong with a flat impedance loading of an amplifier, no matter the topology?
I was the one who brought up Christophe's conjugate network thread and I wish that he would continue it. Perhaps he could do it as a blog and then you don't have as much of the negative comments from those who seem to have a specific answer in mind, no matter any evidence to the contrary. I think and understand that Christophe was correct in his assumptions and reasoning and there was more to go with that. How can you ever go wrong with a flat impedance loading of an amplifier, no matter the topology?
I will, but, you know, i'm retired, not like those people at work with all this free time...😉
Christophe,
I have noticed many times now that some people only seem to post during what I would think are working hours. On the weekends or later at night most of these people get real quite. At least you are semi-retired and I work for myself so I can always write myself up!
I have noticed many times now that some people only seem to post during what I would think are working hours. On the weekends or later at night most of these people get real quite. At least you are semi-retired and I work for myself so I can always write myself up!
The idea is not mine, but came from a friend designing enclosures at "La maison du haut parleur".
No assumptions, but practical improvements with many various Loudspeakers.
Not that kind of improvements you are not sure about, and need careful listening séances to figure out if you are not fooling yourself. Immediate, obvious, and amazing changes that you can hear and measure both in acoustical response curves and waterfalls.
"Faster", more analytical, drier, basses, with no resonances. Suddenly, basses and quick drums are separated, and the hit of the kick hammer on the skin as well as the mediator on the strings are obvious.
Low medium cleaned from halo or impasto, specially on male voices.
Of course, if your enclosure have lack of basses, it will increase this defect.
Well, VSSA can give-you ~ 80W with +-35V DC on 8 ohms.
A 300W Analog PSU will be perfect for one channel. A little undersized (on my taste, i would go for 500VA) for two, but it will work.
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