Great job on these boards and I had tons of fun putting it together and it comes with a laugh as well every time I remember this point about the 'dykes'. In fact, around the house the blade connections have now been nicknamed the 'dykes'. BTW these 'dykes' are made of plated copper alloy, unless you have butter pliers anything will cut them.
On a serious note, I think it would be great to make a opamp based daughterboard that takes balanced input and turns it into unbalanced. Many preamp/DACs out there out there output XLR.
If I wasn't such a nitwit with electronics I would play around with that.
What about a tucson/norwood that combines the lowest THD OPA1611 and the lowest output impedance HA5002?
Anyways if all goes well and UPS shows up soon, I can play some music through this thing by tonite.
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Believe me, the AD744/HA5002 combo is absolute magic. There’s no need to change it.
Balanced to RCA - https://cinemag.biz/line_input/PDF/CMLI-10-600.pdf
Balanced to RCA - https://cinemag.biz/line_input/PDF/CMLI-10-600.pdf
Thanks for the link!
Now I am curious! I take it the AD744/HA5002 is what you are using. The low output impedance to drive the EDCOR makes tons of sense. I don't have the AD744 but I have some sample AD8610, do you think I could swap the AD744?
About the voltage rating of the opamp based boards...what is safe margin? Not that I will go much above +-24V but I hear people go to slightly higher voltages.
Now I am curious! I take it the AD744/HA5002 is what you are using. The low output impedance to drive the EDCOR makes tons of sense. I don't have the AD744 but I have some sample AD8610, do you think I could swap the AD744?
About the voltage rating of the opamp based boards...what is safe margin? Not that I will go much above +-24V but I hear people go to slightly higher voltages.
tucson M2x -'unbuttered' is live!
Overall the easiest build ever. Bias is a rock 1.33A per channel. dc offset was already 2mV I adjusted it to 0.000V. If one can believe the 20 dollar voltmeter.
The trafo is 18-0-18 and the rail2rail s 43.5 VDC + to - a bit too low.
The sound is already great! I do need to finish the ac line power cable etc.. Now is going off a variac and its fuse...
Overall the easiest build ever. Bias is a rock 1.33A per channel. dc offset was already 2mV I adjusted it to 0.000V. If one can believe the 20 dollar voltmeter.
The trafo is 18-0-18 and the rail2rail s 43.5 VDC + to - a bit too low.
The sound is already great! I do need to finish the ac line power cable etc.. Now is going off a variac and its fuse...
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Ya, I like it, lovely simple, I'm old school KISS guy. A simple layout that takes parts away from other parts which may cause problems, is much better than going to extremes to mitigate those influences.
Although that case still makes me think the bomb squad could use it to contain the blast of a, "Uranium P32 modulator."
Nice work brother, keep us informed of your adventures with it.
JT
Although that case still makes me think the bomb squad could use it to contain the blast of a, "Uranium P32 modulator."
Nice work brother, keep us informed of your adventures with it.
JT
Thanks! I switched the variac to the 140V side and fed the trafo a little more Vs to bring up the rail to 24-0-24V after CRC and the sound gets alot cleaner & more detailed. Still, case temp is well under control. Heatsinks at 45C after hours. The hottest part are the Rs in the CRC at 50C and the transformer mounting plate. I guess it's ferromagnetic and it's affected by the flux but that's a heatsource I want to try to eliminate. The mosfets in the active rectifier stay cool.
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I met a lady who told me she met a guy
who had a couple of MoreWood boards on his bench.
She said that he said that MoreWood was more enjoyable than Norwood, and a lot more enjoyable than the other four original IPS boards.
I could be wrong. She could be wrong. He could be wrong. But let us all hope not!
who had a couple of MoreWood boards on his bench.
She said that he said that MoreWood was more enjoyable than Norwood, and a lot more enjoyable than the other four original IPS boards.
I could be wrong. She could be wrong. He could be wrong. But let us all hope not!
I have tried most of the boards so far. All except the Ishikawa. I'm back to the Mountain View, and I like it the best so far.
I used some heat transfer epoxy on the Ishikawa and am worried with some possible shorting between legs of the transfer, where I scraped the material off the bottom of the body. Is there a way to test the boards before sticking them into my amp? I really don't want to burn out part of my amp.
I used some heat transfer epoxy on the Ishikawa and am worried with some possible shorting between legs of the transfer, where I scraped the material off the bottom of the body. Is there a way to test the boards before sticking them into my amp? I really don't want to burn out part of my amp.
I am liking the Tucson the best because that's what took me 1 hr to bolt in and I am enjoying the sound too much to change it.
Someone was too busy with limericks and forgot to add M3 screws in the BOM so I had to improvise.
Norwood-level output currents from Thru-Hole Tucson? Yes! OPA-551!!
DIY project creator Pete Millett has published (and sells boards for) a delightful headphone amp called Butte (here's a link). Amazingly, Butte provides the same gigantic output current (±200mA !!) as M2x Norwood ... but it's a thru-hole DIP8 design. Best of all, the magic chip which Pete uses in Butte, is a available as a single (not dual) thru-hole opamp, unity gain stable, that is pin compatible with Tucson. You can plug one of them straight into the DIP8 socket on your Tucson board, and listen to it, today. No soldering required.
OPA551 datasheet attached below. Don't buy the OPA552, it will break into oscillation if you install it in Tucson. Stick with OPA551.
Want bragging rights? Drop in one of these supercharged nitromethane-fuelled opamps.
_
DIY project creator Pete Millett has published (and sells boards for) a delightful headphone amp called Butte (here's a link). Amazingly, Butte provides the same gigantic output current (±200mA !!) as M2x Norwood ... but it's a thru-hole DIP8 design. Best of all, the magic chip which Pete uses in Butte, is a available as a single (not dual) thru-hole opamp, unity gain stable, that is pin compatible with Tucson. You can plug one of them straight into the DIP8 socket on your Tucson board, and listen to it, today. No soldering required.
OPA551 datasheet attached below. Don't buy the OPA552, it will break into oscillation if you install it in Tucson. Stick with OPA551.
Want bragging rights? Drop in one of these supercharged nitromethane-fuelled opamps.
_
Ok folks quick question (and I googled for this left and right all afternoon):
what should the m2x board current draw? I have seen values such as 1.5-2A from Zen Mod, the power consumption of 160W from First Watt but what should this value be with the M2x board with std components and the prescribed optocoupler?
My amp draws 1.33A at -/+ 24VDC which is 64-something W/channel, which is low: whats' the deal?
what should the m2x board current draw? I have seen values such as 1.5-2A from Zen Mod, the power consumption of 160W from First Watt but what should this value be with the M2x board with std components and the prescribed optocoupler?
My amp draws 1.33A at -/+ 24VDC which is 64-something W/channel, which is low: whats' the deal?
I think you will enjoy reading Nelson Pass's article called Leaving Class A. It's on the First Watt website under the tab "Articles". Scroll down to 2008 and there it is.
A quick review of the M2 / M2x schematic shows that it is a Class A amplifier with a Push Pull output stage: a Pchannel MOSFET source follower actively pulls up the output, and an Nchannel MOSFET source follower actively pulls down the output. Thus Mr. Pass's statements underlined in red are applicable to M2 / M2x.
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A quick review of the M2 / M2x schematic shows that it is a Class A amplifier with a Push Pull output stage: a Pchannel MOSFET source follower actively pulls up the output, and an Nchannel MOSFET source follower actively pulls down the output. Thus Mr. Pass's statements underlined in red are applicable to M2 / M2x.
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Zen Mod put that opto in the schematic, I guess he wants to keep global warming under control.
Zen did what? Not following your line of thought...