Oh you hadn't said you'd had your own boards made - Kubeliks I meant, you did mention about monoAMPs now my memory's been jogged. So I was trying to figure out your context. Now all becomes clearer 
Kubelik using TH resistors I suspect would be at least twice the area of PCB given there are around 80 resistors on it. I would have to look into what non-SMD capacitors could be used.
Kubelik using TH resistors I suspect would be at least twice the area of PCB given there are around 80 resistors on it. I would have to look into what non-SMD capacitors could be used.
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Hi guys. Hope all are well. Slowly populating my bare pcbs for the monoamp R3, seem to be much more proficient and confident with 0805s!
Do the output inductors really have a polarity or 'direction'. Shertzey got creative fitting the big Wurths to his R3 boards as one was 'flipped.' I was just going to mirror one of the big inductors so they would both mount 'face up', rather than flip it and attempt to get to pin#1.
Surely it is just a coil of wire?!
Do the output inductors really have a polarity or 'direction'. Shertzey got creative fitting the big Wurths to his R3 boards as one was 'flipped.' I was just going to mirror one of the big inductors so they would both mount 'face up', rather than flip it and attempt to get to pin#1.
Surely it is just a coil of wire?!
Hi abraxalito, i was trying yesterday with no success. I just could not find that option. Could you PM me first so i could reply?
Hi Guglielmo - I built two of the 'to 11' amps and listened to them, yes they work fine. I was using a lower noise regulator than the LM317 which is on the original monoAMP. It did sound a little clearer than the monoAMP so I swapped the LM317 out of my desktop monoAMPs and got a similar slight improvement. It seems to me that the other changes (bigger caps, fancy inductors) don't make an audible difference. So I now use modified monoAMPs as my reference, not Amp211s.
So far no kits are in the pipe for Amp211s as the parts are much more expensive than for monoAMP so would call for a significant capital outlay and I've yet to see enough interest to justify that, given that to my ears the improvement over monoAMP is limited to the regulator upgrade.
So far no kits are in the pipe for Amp211s as the parts are much more expensive than for monoAMP so would call for a significant capital outlay and I've yet to see enough interest to justify that, given that to my ears the improvement over monoAMP is limited to the regulator upgrade.
Ah, ok, so it is the reg, you mentioned a few posts earlier. Yes, as I currently use your amp design in my system, I would like to get more details, in order to make it easy enough for me to replace the 317 reg. When listening, I always think, slightly more details would be welcome. Enlightenment would be appreciated BR, Ernst
BR, Ernst
I found the schematic on my disk, but turns out the component values are just place holders. Means I've not updated it since we did the PCB layout for it - I'll get on to that and post it when done. There are PCB gerbers too.
The improvement isn't a big one so I'm curious to ask - what are you using for source? Could be your lack of details isn't the amp. For example : if you were using a MkI version of the Deca DAC then the upgrade to MkII is rather a lot bigger than updating the reg on the monoAMP.
The improvement isn't a big one so I'm curious to ask - what are you using for source? Could be your lack of details isn't the amp. For example : if you were using a MkI version of the Deca DAC then the upgrade to MkII is rather a lot bigger than updating the reg on the monoAMP.
Richard, I use an ADI2PRO FSRBE as a DAC in this system. It is a pretty clean and transparent sounding peace of equipment. So I do not see the slight lack of detail in the DAC.
It is not a big deal, yet I would be happy to increase clearness a little bit.
Thanks for the circuit. So this is, what you replaced the LM317 with. Looking forward to the gerbers or a pcb.
Cheers, Ernst
It is not a big deal, yet I would be happy to increase clearness a little bit.
Thanks for the circuit. So this is, what you replaced the LM317 with. Looking forward to the gerbers or a pcb.
Cheers, Ernst
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So this is, what you replaced the LM317 with. Looking forward to the gerbers or a pcb.
The schematic shows an LM317 but that's there merely for the mechanical footprint so this can fit where an LM317 exists on a PCB. I will look out the gerbers.
Please note this is rather an experimental design and it does run rather hot with the PCB layout we currently have. I'd not recommend using it inside a box where the internal temperature is significantly above room temperature. I keep mine in the open. If I were to respin the PCB I'd increase the radiating area.
Hm, ok, will check temperature in my box. It is 1 HE in height and includes 2 big SMPS thingies. Have a look at #41. Maybe some kind of heatsinking via the chassis might be possible...? Richard, I am not in a hurry. If you think, you would rather redo the design in order to support your kits, I am fine by waiting for that.
Yes, I did think that the LM317 would have to leave, yet it took me a few moments.
Cheers, Ernst
Yes, I did think that the LM317 would have to leave, yet it took me a few moments.
Cheers, Ernst
There are quite a few PCBs in line now for production and as I'm not planning on selling the regulator anywhere at present the PCB re-spin will be quite a long time coming. It'll come if I see an opening for a product though.
You could have a chat with @Shertzy to find out what regulator he's been using, I understand its a Sparkos one. He did mention an improvement with that over the LM317.
If you wanted to build your own regulator on perfboard, the 2N2905A is an acceptable substitute transistor for the hot ones in the schematic and that's available in TO-5/TO-39 package which you could heatsink with a clip. This would be a way to get more thermal headroom than my PCB layout.
You could have a chat with @Shertzy to find out what regulator he's been using, I understand its a Sparkos one. He did mention an improvement with that over the LM317.
If you wanted to build your own regulator on perfboard, the 2N2905A is an acceptable substitute transistor for the hot ones in the schematic and that's available in TO-5/TO-39 package which you could heatsink with a clip. This would be a way to get more thermal headroom than my PCB layout.
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