Is that meant to be humorous?
Honestly... how would you do it?
Speaker binding posts have to be exposed to the end user, who is then intended to connect two exposed wires to them (no certification on the wires required unless they're in a wall), and run those to the loudspeaker (also no certification required... could have either of the two terminals connected to the driver chassis and exposed). Even insulated posts are easily accessible by the end user.
Same applies to XLR and a variety of other connectors.
The bottom line is that bonding everything to earth is not a feasible proposition, and as a result, you're much better insisting that people focus on understanding safe design fundamentals so they aren't doing a variety of unsafe things inside a box and hoping that a ground conductor will save their bacon in the event of a serious mistake.
Regards,
Owen
Honestly... how would you do it?
Speaker binding posts have to be exposed to the end user, who is then intended to connect two exposed wires to them (no certification on the wires required unless they're in a wall), and run those to the loudspeaker (also no certification required... could have either of the two terminals connected to the driver chassis and exposed). Even insulated posts are easily accessible by the end user.
Same applies to XLR and a variety of other connectors.
The bottom line is that bonding everything to earth is not a feasible proposition, and as a result, you're much better insisting that people focus on understanding safe design fundamentals so they aren't doing a variety of unsafe things inside a box and hoping that a ground conductor will save their bacon in the event of a serious mistake.
Regards,
Owen
A new run of these boards is now available!
Please see the following thread for details:
http://www.diyaudio.com/forums/soli...ble-here-bal-bal-se-se-lpuhp.html#post3516741
Cheers,
Owen
Please see the following thread for details:
http://www.diyaudio.com/forums/soli...ble-here-bal-bal-se-se-lpuhp.html#post3516741
Cheers,
Owen
when do you think you will have an idea on ordering/delivery timelines?
Also, is there any recommended PSU designs with the dual voltages that is recommended? I am planning to go with a linear power supply and i have some ideas on approaches but i wanted to see what others had done in this area (i've seen the smps approaches in the thread but i suspect i wont do that).
I am planning an amp for multiple channels so i had in mind a shared transformer but dedicated rectifying circuits for each board.
thanks!
It is only worthwhile using separate PSUs if your transformer has multiple pairs of secondary windings. This isolates each PSU and it's Main Audio Ground from each of the other channels.
that was my thinking. for a linkwitz lx521 i could use a transformer with four secondary windings for each channel this would help me with implementation issues relating to ground and hum if i used separate PSU's. but i wanted to check to see if it was worthwhile vs. going for a single transformer and a shared PSU between the fet stages (i would use a shared power supply for the low power stage anyway).
thoughts on the approach?
thoughts on the approach?
I have finally wired the modules into a dedicated chassis. Here are a couple of pic's the internal one is taken when near completion, there was still some insulation to be applied to mains connections and grounding of the switch mode supplies to safety earth.
The supplies are Audio Power DPA500 S-D, you can also see the additional capacitor board AP kindly provided me as a gift for slow delivery. As configured this provides another 4,000uf per rail of filter capacitors for the high current supplies, there is additional space for another 1,000uf per rail, but I wanted to be sure the supply was fine with a more conservative addition first.
So far I am delighted with the sound and it is virtually completely silent as long as I don't connect my sub woofer which appears to create a ground loop.
I would like to be able to bias the amps further into Class A but the DPA500 won't allow it on start up. Nevertheless the amp sounds better than when wired into my previous monoblock amp chassis. These had a 300va transformer per channel for high current and a 60va transformer per channel for the driver stage supplies. These supplies had a dual secondaries per transformer, electrostatic sheilds and Jensen 4 pole capacitors.
Regards,
Rob.
The supplies are Audio Power DPA500 S-D, you can also see the additional capacitor board AP kindly provided me as a gift for slow delivery. As configured this provides another 4,000uf per rail of filter capacitors for the high current supplies, there is additional space for another 1,000uf per rail, but I wanted to be sure the supply was fine with a more conservative addition first.
So far I am delighted with the sound and it is virtually completely silent as long as I don't connect my sub woofer which appears to create a ground loop.
I would like to be able to bias the amps further into Class A but the DPA500 won't allow it on start up. Nevertheless the amp sounds better than when wired into my previous monoblock amp chassis. These had a 300va transformer per channel for high current and a 60va transformer per channel for the driver stage supplies. These supplies had a dual secondaries per transformer, electrostatic sheilds and Jensen 4 pole capacitors.
Regards,
Rob.
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Hello, sometimes it seems that something is moving on this thread..
I'd be curious to know what happened to everyone else with the DPS-600 GB
...I hope it went well.
@ Robert-F: I see cables delicious in the assembly, as well the vertical mounting of the two DPS-500.
From the picture I see you have the "S" version, this includes the remote control, you have not used? works well and is easy with 2-Pin, just "open / close".
The connector (CN4) is located near the vertical module.
As the DPS-600, this remote control in accordance with EEC regulations, has a very small absorption and can keep the stby for a long time.
maybe you can replace the switch on the front, with a circular 23mm diameter with double switches (one for each remote control).
For additional filtering capabilities, 5000uF per side is the maximum stated on the datasheet, I think you'll have a timbre very dry, especially on percussion hehe!
thanks to Qusp for the support
Congratulations to Opc for new projects.
regards
I'd be curious to know what happened to everyone else with the DPS-600 GB
...I hope it went well.
@ Robert-F: I see cables delicious in the assembly, as well the vertical mounting of the two DPS-500.
From the picture I see you have the "S" version, this includes the remote control, you have not used? works well and is easy with 2-Pin, just "open / close".
The connector (CN4) is located near the vertical module.
As the DPS-600, this remote control in accordance with EEC regulations, has a very small absorption and can keep the stby for a long time.
maybe you can replace the switch on the front, with a circular 23mm diameter with double switches (one for each remote control).
For additional filtering capabilities, 5000uF per side is the maximum stated on the datasheet, I think you'll have a timbre very dry, especially on percussion hehe!
thanks to Qusp for the support
Congratulations to Opc for new projects.
regards
It is the mains wire direct to the front panel mains switch
The actual individual conductors are 11 ga so much of the overall diameter is cotton fill, but yes the overall diameter is substantial. I have run ground wires from the aluminium panels on which the supplies are mounted to the safety ground on the iec socket (not done at the time the pic was taken).Nice job.
How much capacitance did you have after those previous transformers?
How much output device quiescent current have you been able to achieve with the SMPS?
What was the delivered price of the pair of SMPS? I don't recall seeing that anywhere so far. I think in the UK I'd pay no VAT. I might want to try a pair at some point in the future.
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Nice job.
How much capacitance did you have after those previous transformers?
How much output device quiescent current have you been able to achieve with the SMPS?
What was the delivered price of the pair of SMPS? I don't recall seeing that anywhere so far. I think in the UK I'd pay no VAT. I might want to try a pair at some point in the future.
Hi IaNas,
The DPS-500-D start with low price, I saw in shop € 140 without VAT
but has no output x LME. someone who asked via email @ infoAP, (as Robert-F), paid a supplement of € 20 each, for lme voltage output. consider that this requires a new transformer rewound.
I believe that these offers are aimed to raise awareness of this fine product.
otherwise, it seems inconceivable to ask the company that produces this power-unit, one or two transformer with different specifications.
Now the time is ripe to understand the substantial differences between one product and another.
--------
Startup-Current: I saw the test sheet right of these he bought Robert-F. since the startup test is repeated both "hot" and cold, it should be comfortable with 2x280mA @ 50V. from the side of the power-unit, this absorption means 2 * 14w = 28w.
from the side of the bias current in the amplifier, this is equivalent (in the case of + /-50V) to 280mA of bias.
This is a guaranteed value with a range of 210-250V VAC.
This limitation, certainly stupid can be overcome with an automatic bias (which I prefer whatever) whereas the DPS-500 supports up to 800mA quiet
Regards
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Hi IanAS,
I ran them at 360ma with the old supply. I couldn't get the power supplies to start up at that idle current and so reduced it to about 280 ma or so. I must see if I can implement switchable higher bias but the last thing I feel like doing right now is pulling the amp to bits again!
I was running 15,000uf per rail on the old high current supplies.
I ran them at 360ma with the old supply. I couldn't get the power supplies to start up at that idle current and so reduced it to about 280 ma or so. I must see if I can implement switchable higher bias but the last thing I feel like doing right now is pulling the amp to bits again!
I was running 15,000uf per rail on the old high current supplies.
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Thanks for that detail Robert, so that's a not too bad supply; 300VA and two 15,000uF of Jensen caps per amplifier, and it's beaten in sound quality by this SMPS.
But it remains to be seen how they'll do against the 400VA and 4 x 10,000uF of Nichicon grade 4 per mono block in my Meridian 605s.
Or the 1000VA and 6 x 10,000uF of Nichicon grade 4 I have ready for the next mono blocks.
But I think it seems a reasonable expectation that two of these SMPS will beat the single 500VA M0 cored Toroid and 40,000uf of standard Elnas in the Hafler DH200. But that's also about £130 for the tx and caps vs. £275.00 for the two SMPS.
But it remains to be seen how they'll do against the 400VA and 4 x 10,000uF of Nichicon grade 4 per mono block in my Meridian 605s.
Or the 1000VA and 6 x 10,000uF of Nichicon grade 4 I have ready for the next mono blocks.
But I think it seems a reasonable expectation that two of these SMPS will beat the single 500VA M0 cored Toroid and 40,000uf of standard Elnas in the Hafler DH200. But that's also about £130 for the tx and caps vs. £275.00 for the two SMPS.
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not that I know of no, they will do +/-65 for FE and +/-55 for mains though. do remember thats after the drop and they will drop much less than even a pretty hardcore unregulated supply. they have fully differential feedback on the high current outs also. check the squarewave response powering this amp at full power posted earlier in the thread, pretty unreal.
When you say 'on load' do you mean quiescent current or full power into 8 Ohms? My pal, below, gets very little rail drop at full power, IIRC he say maybe 1 volt, which would appear to be better than these SMPS are doing at much less power. And his 300Watt mono blocks make about 1000W into 2 ohms continuous using sine wave with no visible clipping. Mine should be bit better as he has 750VA toroids from the same people at the same time that I got the similar spec 1000VA made by and I'll have a bit more capacitance. I like the idea of the 'regulated' rails with this SMPS but I think I'll need a bigger one?
±55V equates to not much power for a mosfet amp. My bipolar amp is only about 100W with it's ±50V rails.
That's OK if you have efficient enough speakers, but I don't. My Hafler might be making perhaps 220W or so (RMS per channel into 8 Ohms) and the VU meter someone gave me flashes it's 200Watt light from time to time without the music seeming particularly loud. Maybe it's faulty, I don't know. But a pal with similar speakers made his own VU and that indicated upper power (about 220Watts) nearly all the time at normal listening level in his sound proofed and well damped room from a beefier and better amp he made that was similar to that Hafler. He went up to 300Watts after that with the same boards and two more mosfets, but two bigger Tx instead of the one, and the transient response was far better.
±55V equates to not much power for a mosfet amp. My bipolar amp is only about 100W with it's ±50V rails.
That's OK if you have efficient enough speakers, but I don't. My Hafler might be making perhaps 220W or so (RMS per channel into 8 Ohms) and the VU meter someone gave me flashes it's 200Watt light from time to time without the music seeming particularly loud. Maybe it's faulty, I don't know. But a pal with similar speakers made his own VU and that indicated upper power (about 220Watts) nearly all the time at normal listening level in his sound proofed and well damped room from a beefier and better amp he made that was similar to that Hafler. He went up to 300Watts after that with the same boards and two more mosfets, but two bigger Tx instead of the one, and the transient response was far better.
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