Where
Where did you get the case from
Where did you get the case from
Where
Where did you get the case from
Last week, I finally got to build up my first amp in the Ghent cases I've wanted. Sadly, the amp did not impress. In fact, it was bad. Weak (low output), unexpectedly noisy and lacking bass. I tried different input cables, different source outputs, both channels - no change. Must be the power supply, somehow... Afterall, @phoenixdogfan had SMPS problems. So, available weekend time was spent on ultimately unnecessary troubleshooting. Cutting to the chase, all of the RCA->XLR input cables I bought most recently were bad: signal(-) was soldered to pin 1 and they had no connection to pin 3! After reworking the connections, I now have normal operation. I have no critical listening observations to add, other than to say, it no longer sounds like crap!
I did two types of build: vain (because I wanted it my way); and sane (because it's easier and more than adequate). I'll post pictures and few details later.
Pls don't tell me you bought it from Ghent!Last week, I finally got to build up my first amp in the Ghent cases I've wanted. Sadly, the amp did not impress. In fact, it was bad. Weak (low output), unexpectedly noisy and lacking bass. I tried different input cables, different source outputs, both channels - no change. Must be the power supply, somehow... Afterall, @phoenixdogfan had SMPS problems. So, available weekend time was spent on ultimately unnecessary troubleshooting. Cutting to the chase, all of the RCA->XLR input cables I bought most recently were bad: signal(-) was soldered to pin 1 and they had no connection to pin 3! After reworking the connections, I now have normal operation. I have no critical listening observations to add, other than to say, it no longer sounds like crap!
I did two types of build: vain (because I wanted it my way); and sane (because it's easier and more than adequate). I'll post pictures and few details later.
My "sane" build:
- Ghent binding post case, with standard gold-plated brass CMC posts (not on their website)
- DELRON output sockets and S1 removed
- 1 ohm, leaded feedback safety resistors added
- Feedback from on the post, rather than the solder pool of the output wires
- 15 AWG bus wire output connections (18||18)
- Arctic MX-4 thermal paste under the SMPS and amp modules
- Fused mains filter, with X-Caps disconnected from ground
- Star quad mains wiring, 15 AWG (18||18)
- Tightly wound SMPS interconnects, with nAMPON and nFATAL implemented
I think the DELTRON-style are very good. If you want to use them, the standard Ghent EVAL1 case, including speakONs, is a good way to go.Did you just not like the Delron-style speaker connectors?
Any measured thermal performance improvement with the paste and/or heat sinks?
I think the DELRONs are very good. If you want to use them, the standard Ghent EVAL1 case, including speakONs, is a good way to go.
http://www.ghentaudio.com/kit/purifi-eval1-se.html
But, if you want binding posts, and you want to use feedback from them, you must remove the DELRONs. This is what Purifi did on their demo amps. Otherwise, the feedback is from the DELRONs, on the PCB.
The benefit of a little, high quality thermal compound, applied well, will be slightly lower heatsinked component temperatures. How much cooler depends on the exact thermal contact without it, and the power level being used at the time. I didn't go crazy here. Early in the year, I planned to send one of these to Amir to see how whether his power test would run without shutting down (as it did on the Purifi build), but it doesn't seem that interesting after all this time.
I do like the venting details of this Ghent case. It is important for the temperature of the components that are not directly heatsinked, and is very much like what I suggested they use.
FYI, here is how Purifi wired their own demo box with dual outputs (on-board DELRONs plus 4-pole speakONs):
View attachment 92604 View attachment 92606
There are two wires for "black", from the two open holes in the FE02 board, connecting to the top and bottom tabs, . If you do this, solder from the top surface of the PCB - that's where the trace is. The same goes for leads to the side tabs from the "red" PCB holes. They used bare bus wire, but note the addition of red insulation to ensure no accidental output short on the wire that crosses behind the lower one from black to the left-hand tab. I'd solder the wires from the PCB first, before case assembly.
That would be really bad. Open loop means maximum gain. Output would go to the limit. I'd expect to blow any common tweeter. BUT, I have certainly not tested that! Anyway, you can argue that any of several single component failures could do the same, or maybe worse. Really, in a properly built unit, it should not be a real risk. It is mostly a risk for DIY - getting it wrong.Hi, I'm wondering about the 1 Ohm resistors. I have the feedback wires soldered very well. The risk of one getting broken is very low. But what would happen if that one got broken. I read the amp than has an open loop. But would it break the speakers or the amp? Or would it just sound not as good?
Thanks!
Yes. Soldering those wires onto the top layer of the board, well, with the DELTRON-type sockets in place, is not trivial.My amp is just an EVAL1 + Hypex SMPS in the standard Ghent EVAL1 case. I haven't soldered the Speakon connectors yet, working my way up to that. A little timid about scorching the buffer board, I'm still a novice with the iron.
I understand the theory of using thermal grease. It'd be interesting to measure it. I think the data sheet says the thermal cutoff is 75C? Do you have a temp probe? Is Amir's power test representative of playing music, even at high levels?
What part did you use for the SMPS heat sink, or did you custom cut one to size?
I'd rather have seen smaller "pinhole" style venting like Ghent uses on their Hypex cases. The longer slot-style venting on the top cover seems like asking for paperclips to fall inside.
YES! It (DELTRON) was molded in the tops of early sockets we saw pictured, but not once they went into production (none of my 16 sockets are marked at all). I suspect they are not the brand used anymore. My references should be "DELTRON-style". I'll fix some of those as I see them...Is 'Delron' just a typo that's stuck? Deltron is a reasonably well known manufacturer of similar terminals:
https://www.dem-uk.com/deltron-comp...ctors/4mm_90deg_pcb_mounted_insulated_socket/
Measuring thermal paste improvement requires two, precisely comparable builds, assemble the two different ways. I'll likely do a simple temp check with a low test load at some time...
I'll keep that in mind. The most useful tests will be with top cover in place.My unit is pretty much identical to yours, just without paste or additional heat sinks. If you describe your test method (including probe locations) I can try to do the same and measure. There will still be a lot of variables (different test equipment, different ambient temp, etc), but I'm happy to give it a try.
Ok. I've looked at this and retested a couple of ten times.AMPEN doesn't look right. It looks like the PS is going into standby mode. Need you to measure all these relative to GND and report back :
SMPS Stand-by
Amp Standby
DC-Error
Amp Enable
See page 7 of the Hypex PS datasheet for signal details.
https://www.audiosciencereview.com/forum/index.php?attachments/smps1200axx0_09xx-pdf.49157/