Bigman80
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Post by Bigman80 on Jan 18, 2024 23:36:42 GMT
I will be documenting the stages of my Purifi build on this thread. Part One - PCBs So, ordinarily you'd start a build like this with some brand new PCBs, but I grabbed these off eBay:  So I will share the links to where you can buy these parts Instead. Purifi PCBs : www.soundimports.eu/en/purifi-1et400a.htmlThese are only the amplifier modules. You then need to decide what buffer PCB you want to use. There is the native Purifi one, one from Neurochrome, VTV....plus more. The VTV ones I have are here: vtvamplifier.com/product/vtv-amplifier-custom-input-buffer-hypex-nc500-nc1200-nc2k-purifi/These come with Opamp options. Mine came with Sparkos, but I will be changing them to OPA1612 or OPA1656 ASAP. To do that, I will need adapter PCBs from SOIC-8 TO DIP-8! Found here: www.cimarrontechnology.com/product/browndog-020302-single-to-dual-op-amp-adapterThese guys will fit the opamps for you, just select from the drop down menu! Next, PSU. Yes, I am going against my own advice and putting a large SMPS in. The reason for this is actually quite simple....I have not currently got time to make a PCB layout with the correct voltages. I am also not cash rich at the moment after commissioning new speakers, so for now at least...SMPS. I bought this one: kjfaudio.com/product/hypex-smps1200a400/Honourable mention: The fella at KJF is a top banana. One of the queries I raised with him was how to use one SMPS with two Purifi PCBs. There are splitters designed to allow multiple connections from the white 6 pin connector, like this one: neurochrome.com/products/hypex-smps-splitter - but none for the ribbon cable. See here:  As you can see, the VTV buffers require one each, but the Hypex1200a400...only has one socket. He has made me a cable he thinks will work. It may not, but that is a really great bit of customer service. If it doesn't work, VTV sell this one: vtvamplifier.com/product/vtv-amplifier-hypex-input-buffer-ribbon-cable-nc1200-nc2k-two-14-pin-ends/Link for the 6-pin splitter I have bought: www.ghentaudio.com/products/psc-23Next...Casework and Connections |
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Post by gninnam on Jan 19, 2024 11:03:58 GMT
Time to get the popcorn  As mentioned many times a well put together SMPS PSU can work very well. |
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Arke
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Post by Arke on Jan 19, 2024 13:26:22 GMT
Excited to see this come together. It's gonna be epic. I'll document the build of your speakers too. Drivers arrive on Monday 😀
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Bigman80
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Post by Bigman80 on Jan 19, 2024 14:39:23 GMT
Excited to see this come together. It's gonna be epic. I'll document the build of your speakers too. Drivers arrive on Monday 😀 Now I'm getting excited! |
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Bigman80
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Post by Bigman80 on Jan 19, 2024 22:42:09 GMT
Part Two:
A small detour from the next part, which was supposed to be "Casework and Connections"
Instead, it's now:
"Buffer PCB modification"
Yes, the VTV buffer boards made by "Sparkos" are in fact....cack. Well, not quite, but the comparative measured performance between this design and the Purifi design by Bruno is quite staggering. Thankfully ASR have kindly done the legwork here and identified the issues regarding the buffers, so i am going to rectify them here too.
First job is to remove the SS78XX & SS79XX Discrete regulators, and fit some PROPER regulators. This *SHOULD* prevent the PSU noise from seeping into the buffer...something the SParkos seem unable to do currentl;y as evident in the ASR tests.
Secondly, remove those Opamps for a pair of 1612 & 1656 Opamps. The datasheet for these Sparkos devices should be warning enough, but i suspect no one reads them.
Also, it appears i DO need that ribbon cable as they supply the voltage to the opamps on the buffers. So, i'll check the cable from KJF and if that doesnt work...i'll buy one from VTV.
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Arke
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Post by Arke on Jan 20, 2024 7:13:43 GMT
As usual, you're going to an impressive level of detail - big kudos! This is gonna be a very special build.
(which boards has my amp got? 😂)
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Bigman80
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Post by Bigman80 on Jan 20, 2024 22:08:36 GMT
As usual, you're going to an impressive level of detail - big kudos! This is gonna be a very special build. (which boards has my amp got? 😂) Yours has these: purifi-audio.com/shop/eval1-eval1-stereo-1et400a-evaluation-kit-1610#attr=263,264,265,266,7890,268,269,270,271,272 Which according to the ASR measurements are the best, although the Neurochrome ones haven't been measured...But there is a reason i don't want those ones either. That's for another day. |
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Bigman80
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Post by Bigman80 on Jan 20, 2024 22:15:52 GMT
Part three: Casework and connections! With the new regulators and Opamp carriers ordered, i am now on to casework and connections. Usually i would go for CMC binding posts and WBT RCA sockets. However, i am going with EIZZ (low mass) binding posts and WBT RCA sockets. The EIZZ binding posts are here: www.ebay.co.uk/itm/333673760310?mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338757644&toolid=20006&customid=3de7a9a0cca87691823745a882b90797I have used these before and they really are gold plated copper! I kind of want to go full WBT on the back. Both binding posts and RCAs...but the price! Casework: Hmmm. I have bought a box, but it isn't doing it for me. It's very big and this build really doesn't need the space, so i think i am going to build a BBU into that and get a different case. I am thinking something with a low profile and smaller footprint. I'll post a link when i have decided. Oooooh! I forgot. For anyone wondering, the Sparkos regulators are SS7915 & SS7815..so 15v + & - for replacements. Pick your own to suit. |
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Post by stevew on Jan 21, 2024 8:31:31 GMT
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Bigman80
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Post by Bigman80 on Jan 21, 2024 8:39:18 GMT
Did you need 8 channels?! 😂 |
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Post by stevew on Jan 21, 2024 8:51:19 GMT
lol… well, the Arcam had 7 (with a centre speaker).
To be honest I’m not really missing the surround sound malarkey. Now I’ve got the telly plumbed into the main system, the Ektas are filling the room with low frequency stuff from movies amazingly well.
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Bigman80
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Post by Bigman80 on Feb 3, 2024 20:12:06 GMT
Painfully slow progress i'm afraid to report. The casework still isnt here, which is unfortunate but the regs are here! Still awaiting the opamps though. SOOOOOOOO slow. A few pics of the case I have opted to use for this build, and yes, it will have both XLR and RCA.    |
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Arke
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Post by Arke on Feb 3, 2024 23:31:01 GMT
Nice case Oli. It's gonna look lovely
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zleepy
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Post by zleepy on Feb 5, 2024 8:09:55 GMT
That's a very good looking case. A pity they have to put their logo on the front. That's the only thing I would change. It will look superb with the pre drilled holes in the back plate.  /Karl |
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Bigman80
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Post by Bigman80 on Feb 5, 2024 9:05:10 GMT
That's a very good looking case. A pity they have to put their logo on the front. That's the only thing I would change. It will look superb with the pre drilled holes in the back plate. /Karl Yeah, I agree. The logo is crap but the case ticks all the other boxes. Should be here within the next 10 days apparently. |
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Bigman80
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Post by Bigman80 on Feb 15, 2024 22:50:30 GMT
So, I finally have the regulators and the opamps here and now I can make a start! First job is to remove the current regulators and replace them, remove the spade connections for the speaker output and replace with chunky CCC copper and then tomorrow I'll be attaching the opamps to the BrownDog mounting boards. Fun! I've got one buffer PCB done...other tomorrow as I've been up since 4am!  |
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Bigman80
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Post by Bigman80 on Feb 16, 2024 13:13:51 GMT
A little mock up  |
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Post by gninnam on Feb 17, 2024 10:53:51 GMT
Looks neat and tidy and plenty of space to work in |
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Bigman80
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Post by Bigman80 on Feb 17, 2024 13:52:37 GMT
Looks neat and tidy and plenty of space to work in Should be tidy when it's done. To be fair, it would have been just as cheap to buy one fully built 😂😂 However, this one will be how I want it to be. |
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Bigman80
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Post by Bigman80 on Feb 18, 2024 15:05:53 GMT
Trying to get this BBU finished so I can get on to the Purifi build! New speakers arrive early/mid March!!!! And yes, I know the power inlet is on the wrong side 😂   |
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Post by mikeyb on Feb 21, 2024 15:36:55 GMT
I'm surprised this hasn't been finished and sold off by now  |
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Post by electronumpty on Feb 21, 2024 16:20:33 GMT
I'm surprised this hasn't been finished and sold off by now 🤣🤣🤣 |
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Bigman80
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Post by Bigman80 on Feb 21, 2024 16:25:28 GMT
I'm surprised this hasn't been finished and sold off by now 😂 If only....still assembling that BBU. Hopefully that will be done this weekend and then the Purifi the week after. |
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Arke
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Post by Arke on Feb 21, 2024 18:30:38 GMT
I'm surprised this hasn't been finished and sold off by now 😂 If only....still assembling that BBU. Hopefully that will be done this weekend and then the Purifi the week after. Then not long until new speakers.... |
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Post by mikeyb on Feb 21, 2024 18:41:48 GMT
😂 If only....still assembling that BBU. Hopefully that will be done this weekend and then the Purifi the week after. Then not long until new speakers.... I'm putting an offer in for them tonight 😉😂 |
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Post by pete on Feb 21, 2024 19:33:20 GMT
Then not long until new speakers.... I'm putting an offer in for them tonight 😉😂  |
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Bigman80
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Post by Bigman80 on Feb 21, 2024 20:15:44 GMT
Then not long until new speakers.... I'm putting an offer in for them tonight 😉😂 At least let me hear them once |
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Post by mikeyb on Feb 21, 2024 20:16:40 GMT
😂
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Arke
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Post by Arke on Feb 21, 2024 20:50:58 GMT
Then not long until new speakers.... I'm putting an offer in for them tonight 😉😂 Don't think Oli would speak to me again! |
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Post by mikeyb on Feb 21, 2024 20:54:07 GMT
Don't think Oli would speak to me again! Aye probably not 😂 |
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