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DIY Purifi Amp builds

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Hi,

Ok, finished my amp, everything checks out, no hum or line noise and sounds pretty nifty (scientific terminology).

Next step, move everything up to the loft and setup up a listening room. Yay!

Next amp build, four EVAL 2 mono blocks in individual cases with their own power supply's to bi-amp my speakers.


John

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JimB

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Thread Starter #2,106
...
Next amp build, four EVAL 2 mono blocks in individual cases with their own power supply's to bi-amp my speakers.

John

Complicated solutions for non-existent problems
Why not two stereo cases for your biamping needs?
 
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That sounds great!

Waiting for more impressions later

Did you build those speakers? they look really nice indeed.

Any closer pictures?
Hi Sami,

No, I did not build the speakers, but I will build the next pair. They are Pure Audio Project Duet 15 Preludes....I wanted an open baffle and I wanted a pair of Spatial M5 Sapphires, but Clayton did not respond to my emails after repeated inquires due to room sizing. He finally did respond, but after I purchased the PAPS.

John
 
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Why not two stereo cases for your biamping needs?
Hi Jim,

Well, I could build a stereo case with a single power supply in the middle and in fact I was going to do exactly that. But I'm also not a very practical person and I like to machine stuff. I also like the looks of individual long, narrow cases with individual power supplies and multiple pieces and parts. Plus, I have nothing else to do on this mountain top in TN. :)

John
 
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JimB

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Thread Starter #2,109
Hi Jim,

Well, I could build a stereo case with a single power supply in the middle and in fact I was going to do exactly that. But I'm also not a very practical person and I like to machine stuff. I also like the looks of individual long, narrow cases with individual power supplies and multiple pieces and parts. Plus, I have nothing else to do on this mountain top in TN. :)

John
I was envisioning a stereo amp right behind each of your speakers to do your biamping right there, not from a center location. You could still machine it yourself, even with an EVAL-1 inside! You'd save a bit for the gold plating. :p Personally, I HAVE done gold lettering on a face plate, in the past...
 
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I was envisioning a stereo amp right behind each of your speakers to do your biamping right there, not from a center location. You could still machine it yourself, even with an EVAL-1 inside! You'd save a bit for the gold plating. :p Personally, I HAVE done gold lettering on a face plate, in the past...
Hi Jim,

Yes, that was exactly what I was going to do with four monoblocks , two behind each speaker. I was thinking of also building a chassis for the open baffle speakers and attaching the amps to the back of the chassis and maybe use Baltic Birch to mount the speakers and then to the chassis......kind of like the Pure Audio Project Trio 15's.
 
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Hi Jim,

Yes, that was exactly what I was going to do with four monoblocks, two behind each speaker. I was thinking of also building a chassis for the open baffle speakers and attaching the amps to the back of the chassis and maybe use Baltic Birch to mount the speakers and then to the chassis......kind of like the Pure Audio Project Trio 15's.
I too have (active crossover) open baffle speakers with lot's of amp channels!
 
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I too have (active crossover) open baffle speakers with lot's of amp channels!
Hi Jim,

I need to start researching active crossover components, what are you using and do you have any recommendations?

I looked at one unit......the Model K231 , Rev 3.2 Sublime Acoustic, LLC.

Thanks.

John
 

woodyohill

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I just finished assembling the EVAL1 into the Ghent Audio case using Richard Verhart's very clear instructions. Is that it to get the basic EVAL1 going? I read in the earlier pages here that there are concerns (as cited by March Audio) about the EVAL1 being an open loop? Does that it there is a possibility that it could output ultra-high frequencies and risk frying the tweeters?

I am pretty much a newbie in DIY audio, having only put together a few ICEPower amps many years ago. For me to use the Speakon connectors supplied by the Ghent turnkey solution, exactly where do I need to solder? And must I remove the Banana connectors?

Lastly, am I right to assume that as everything fits so well in the Ghent case, if I end up messing with input buffer boards, that will just ruin the point in using the Ghent EVAL1 case?

Thank you in advance!

PS: Since I took the photo I have connected the power switch wires.

202102170301-006.jpg
 
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Thread Starter #2,115
I just finished assembling the EVAL1 into the Ghent Audio case using Richard Verhart's very clear instructions. Is that it to get the basic EVAL1 going? I read in the earlier pages here that there are concerns (as cited by March Audio) about the EVAL1 being an open loop? Does that it there is a possibility that it could output ultra-high frequencies and risk frying the tweeters?

I am pretty much a newbie in DIY audio, having only put together a few ICEPower amps many years ago. For me to use the Speakon connectors supplied by the Ghent turnkey solution, exactly where do I need to solder? And must I remove the Banana connectors?

Lastly, am I right to assume that as everything fits so well in the Ghent case, if I end up messing with input buffer boards, that will just ruin the point in using the Ghent EVAL1 case?

Thank you in advance!

PS: Since I took the photo I have connected the power switch wires.
What is your mains voltage? IF ~115VAC, you need a jumper on the SMPS J3.

A suggested way to connect speakONs was addressed many pages ago in this topic. For example, here, where all four poles of the speakON are connected:
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-86#post-564666

As for using other input boards, I'd say yes - there is less than no advantage to using the Ghent case because your new assembly might not fit, the cables likely will not be sufficient and the back panel will be wrong.

I don't know what the concern is regarding being "open loop". This amp, properly assembled, should work like any other (only better!;)).

On first power up, definitely check that your output voltages are safe, both with and without inputs connected, before connecting speakers.

"Richard Verhart"?
 
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woodyohill

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What is your mains voltage? IF ~115VAC, you need a jumper on the SMPS J3.

A suggested way to connect speakONs was addressed many pages ago in this topic. For example, here, where all four poles of the speakON are connected:
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-86#post-564666

As for using other input boards, I'd say yes - there is less than no advantage to using the Ghent case because your new assembly might not fit, the cables likely will not be sufficient and the back panel will be wrong.

I don't know what the concern is regarding being "open loop". This amp, properly assembled, should work like any other (only better!;)).

On first power up, definitely check that your output voltages are safe, both with and without inputs connected, before connecting speakers.

"Richard Verhart"?
Thanks! Actually this is for a 220V build, so all good there. Thanks.
And thank you for the SpeakOn post. Will give it a go. Do you know what gauge I need for the bare bus wire?
Measuing voltage... ok sorry but how? I assume just measure the outputs using a multimeter set to AC?
 
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Thanks! Actually this is for a 220V build, so all good there. Thanks.
And thank you for the SpeakOn post. Will give it a go. Do you know what gauge I need for the bare bus wire?
Measuing voltage... ok sorry but how? I assume just measure the outputs using a multimeter set to AC?
I'd say 18, preferably 16, with a good joint and fillet of solder on the PCB pad. You'll need some heat for that. I'd do the 'inside' black pad first, then the outer black and red ones that are more accessible.

Measure both AC and DC on the outputs. As long as there are no large values there (say, <0.2V), it will be safe to connect speakers and listen for your final tests.
 

woodyohill

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I'd say 18, preferably 16, with a good joint and fillet of solder on the PCB pad. You'll need some heat for that. I'd do the 'inside' black pad first, then the outer black and red ones that are more accessible.

Measure both AC and DC on the outputs. As long as there are no large values there (say, <0.2V), it will be safe to connect speakers and listen for your final tests.
Thank you! Couldn't wait to get the Speakon connected. Just had a listen! Fantastic!
 

daniboun

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Hi

Could you please share the cad file to drill the H2000 GX283 or 388 case please ?
Or do you Know if modushop Can provide it ?

Thanks
Danny
 
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