I am re-purposing an old PA amp case for my Purifi build
Nice as the in/out jacks are all there (Neutrik XLR and Speakon) as well as IEC power jack and on/off etc.
I will be using Hypex 1200 power supply.
What is a reasonable breaker size?
The breaker in the case now is 15amp.
Thanks,
DB in MN
Nice as the in/out jacks are all there (Neutrik XLR and Speakon) as well as IEC power jack and on/off etc.
I will be using Hypex 1200 power supply.
What is a reasonable breaker size?
The breaker in the case now is 15amp.
Thanks,
DB in MN
Still...
I am still not sure what your point is? It is EZ to replace the antiquated 7815 regulator with a much lower noise, and lower impedance type for me, and not costly either. Whether it will, or not, make a difference I will not know until I try it: or I might just do it and feel good about having a much better part in a critical location. One can "suppose" it will make a difference, or not, I would really not care about such things.
I prefer to build my own amp. I can do so at less cost than purchasing something from one of the providers out there, and I can end up with something which has much better layout and fits into my system better. I can also choose my power supply arrangement, and use a linear based supply to feed the +- 18 VDC for the OPAs and modulator on the eval board. As the eval board already has onboard (I would guess with good PSRR at high frequencies, that is usually the advantage to going discrete) discrete regulators it probably will not make a difference to use a linear supply here vs a separate SMPS, but why not, at these low current rates using a linear is easy and does not really hurt overall efficiency.
If you prefer to purchase something made by someone else, be my guest, but I would prefer to build something more suited to my needs, spend less cash, and perhaps even improve the performance. The only comparison I am interested in is with my current NC-400 based amplifier, and the NC-1200 based commercial amp I have here...
I am still not sure what your point is? It is EZ to replace the antiquated 7815 regulator with a much lower noise, and lower impedance type for me, and not costly either. Whether it will, or not, make a difference I will not know until I try it: or I might just do it and feel good about having a much better part in a critical location. One can "suppose" it will make a difference, or not, I would really not care about such things.
I prefer to build my own amp. I can do so at less cost than purchasing something from one of the providers out there, and I can end up with something which has much better layout and fits into my system better. I can also choose my power supply arrangement, and use a linear based supply to feed the +- 18 VDC for the OPAs and modulator on the eval board. As the eval board already has onboard (I would guess with good PSRR at high frequencies, that is usually the advantage to going discrete) discrete regulators it probably will not make a difference to use a linear supply here vs a separate SMPS, but why not, at these low current rates using a linear is easy and does not really hurt overall efficiency.
If you prefer to purchase something made by someone else, be my guest, but I would prefer to build something more suited to my needs, spend less cash, and perhaps even improve the performance. The only comparison I am interested in is with my current NC-400 based amplifier, and the NC-1200 based commercial amp I have here...
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I am going to use a +-18V instead when it arrives in the post, and then I will use the DIYinHK super reg +-15V to power the Neurochrome Buffer. Later, when I replace the FE02 connection board with Tom Christensen's adapter boards, I will use a second DIYinHK superreg at +-12V in place of the +-18V to drive the modulators, and then I will think at what to do for the gate driver.
Having fun!
What makes you think the National opamps will outperform the OPA 1612'a powered by Bruno Putzeys discrete regulator? Did you find some IMD specs somewhere?
There's already a fuse on the SMPS1200 input. So your chassis fuse will only be in case there's a short between the mains inlet and the power supply. In this case what you already have will be fine.
I really like the idea tomchr from Neurochrome is proposing for an adapter board.
- mono
- breakout
- high quality buffer
(- ability to use alternative buffers if that's what someone really wants)
Allows immediate construction/evaluation of a mono amp
DIY Purifi Amp builds | Page 18 | Audio Science Review (ASR) Forum
- mono
- breakout
- high quality buffer
(- ability to use alternative buffers if that's what someone really wants)
Allows immediate construction/evaluation of a mono amp
DIY Purifi Amp builds | Page 18 | Audio Science Review (ASR) Forum
Yes...
Those sound like good features. Mono is a must considering the Purifi eval board is not and would guarantee sales for Tom. I would like to see the option to choose the onboard regulators, perhaps a traditional 781x three hole pattern. I am not convinced that just using something like LT-3045 is the best option...
Those sound like good features. Mono is a must considering the Purifi eval board is not and would guarantee sales for Tom. I would like to see the option to choose the onboard regulators, perhaps a traditional 781x three hole pattern. I am not convinced that just using something like LT-3045 is the best option...
Mike has a setup for measuring ripple noise down to 0.4uV. And he said with the right surrounding components, the LT3045/3094's have 10x less ripple noise, higher PSRR, and lower output impedance than the Belleson SPX. He made a bunch of TO-220 format regulators based on them for a DAC project that was cancelled. He has no use for them and is willing to sell for $20 each. Can be set to any voltage up to 18v + or - by changing the value of R1.
Attachments
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Mike Davis of Mivera Audio (aka banned/sin bin members bavmike, Audio Freak, and Class D)...
Do you mind posting this sale ad in the Swap Meet section? And please, everybody, take a look at the middle row of these “buffers” (correction...regulator) and count to the 5th one starting from the left. You’ll see that part C3 exhibits poor soldering or is blown off. Is this the kind of reliability that Mike Davis wants to sell? Is this a matter of pride? Or perhaps you have DETAILED measurements to show the superiority of these regulators and how you have proven beyond a reasonable doubt that they measure better than a Belleson SPX, without resorting to a datasheet?
I didn’t think so.
But please before you sell these units, test each one, give your customers a return guarantee and fix the one I have referenced.
Anand.
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Sorry I'm not selling these. Just seen them on his forum and thought some people might be interested. Yes looks like the cap on 1 of the regulators isn't centred on the pad. Good eye. Although it would only be a purely cosmetic flaw if the cap is still contacting the pads. If you want further data on them you'll have to contact Mike. Mike said he used Belleson's for years and switched to these after measuring them and comparing them with listening tests. They measured better, and he couldn't hear a difference. So it was a no brainer for him to switch.
Sonic Bliss. We take a dim view of people who sign up to be the mouth piece of a previously banned member. You are now trying to promote that previously banned members business. In another vendors thread of all places. If you want to participate in this forum then I suggest that you do so in a completely non-commercial way that does not show a clear agenda, and desist from mentioning Mike or his business.
edit: correction, this isn't a vendors thread, I was confused with Tom's thread in vendors bazaar. but regardless commercial posts outside of a commercial forum or vendors bazaar are not allowed.
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I, as well as others, suggested this long ago. It is on their list of things to consider, down the road. But, from earlier interviews, they really are not doing products for DIY - they are just making available to DIY buyers, what they had, already. They don't want to compete with their OEM customers.
Mike, it really doesn’t matter how good or bad a product sounds if an assembly issue results in poor reliability. This should’ve been discovered by the manufacturer, period. Hours of frustration can be avoided on the part of your clients (and perhaps yourself) if suddenly a regulator stops functioning due to a cold soldering joint. This is the diyaudio forum. Let’s not sell a product as “reliable” under false pretenses or pretend we are not or have nothing to do with Mivera Audio when the evidence clearly points the other way.
Anand.
And now with a linear power supply for the EVAL1 circuitry modulator, using a "lost and found" transformer and the DIYinHK 0.56uV Ultralow noise DAC power supply regulator at 15V.
I am going to use a +-18V instead when it arrives in the post, and then I will use the DIYinHK super reg +-15V to power the Neurochrome Buffer. Later, when I replace the FE02 connection board with Tom Christensen's adapter boards, I will use a second DIYinHK superreg at +-12V in place of the +-18V to drive the modulators, and then I will think at what to do for the gate driver.
Having fun!
Can someone be so kind to take close up pictures of Purifi 1et400a modulator, and other up close pictures without the 3d bar-code sticker.
Many thanks.
Isn't it? Smoother than the NC500 in the upper treble. Extraordinary grip on the bass (but I suppose with more "normal" speakers than mine the extra power of the NC500 would come very useful - biamp with a SET on the tweeter(s) and you get a similar sound but with more power).
I could not have imagined it before firing it up.
On your forum, where you paid 1000$ to yourself in order to talk to yourself and disappear from here, which you announced three times.
No, we are not interested. We know how to get little 78xx compatible three pin regulators based on the LT3045. There are even some on aliexpress, and I do not really see the point of faking a LT3045 so they ought to be the real deal.
More Listening
Did a bit more listening before taking it apart for my final assembly which will have to wait until Monday or Tuesday,,, I am a musician in the Twin Cities, always booked but weekends are crazy.
I found the highs to have less "spotlight" but more spatial information than anything I've ever used. Bass (one of my instruments along with piano/Hammond/Rhodes) is extraordinary. Really pleased by a smooth and MUSICAL character that still has all that detail that is of interest to many of us.
Now I must finish my assembly and later in the month will be doing my seasonal speaker swap to Magnepan III's. That will be interesting.
DB in MN
-2°c on a Saturday, 9:30am
Did a bit more listening before taking it apart for my final assembly which will have to wait until Monday or Tuesday,,, I am a musician in the Twin Cities, always booked but weekends are crazy.
I found the highs to have less "spotlight" but more spatial information than anything I've ever used. Bass (one of my instruments along with piano/Hammond/Rhodes) is extraordinary. Really pleased by a smooth and MUSICAL character that still has all that detail that is of interest to many of us.
Now I must finish my assembly and later in the month will be doing my seasonal speaker swap to Magnepan III's. That will be interesting.
DB in MN
-2°c on a Saturday, 9:30am