The only thing that made sense to me is that maybe the trans are too small and dropping in voltage such that the zener stack isn't fed properly anymore. That will be what I try to chase down tonight. But on the surface, it is not something I expected, but since someone else had seen it too, it seemed a nice rabbit trail to chase.
That would make sense. I would think a low voltage tap on a trafo like that would be to power small accessory circuits, so wouldn't have a lot of current behind it, though this circuit really doesn't require that much current.
The Avels are, I think, 30VA each. We are thinking they will be around $30-$33 per pair, but depends partly on shipping cost to us and how many we buy.
EDIT: 30-0-0-30 trafo is 50VA
The Avels are, I think, 30VA each. We are thinking they will be around $30-$33 per pair, but depends partly on shipping cost to us and how many we buy.
EDIT: 30-0-0-30 trafo is 50VA
I am using the Avel 30 VA on the high side as it looked like that could supply enough current and I already had two for an Aleph P1.7. It just does not make sense that two power supplies alone could drag the voltage down before I even hook up the preamps. What I found was the bizarre behavior with no preamps hooked up. Of course, once it looked bizarre, I was reluctant to hook up the preamps. And I did recheck each PS separately with no problems. Will check currents tonight and may even have to power up the scope. Something very curious that I am sure will end up being cockpit error.
I doubt it. It was duplicated a thousand miles away. Things don't get better with a load on the PS. I tried that.
It does not make sense.
Now since I know that my pair are working just fine, if you see values like that unloaded you can be pretty sure yours will too. 😉
Russ,
Thanks for checking. I am heading home now and will do some checking on my end. I am beginning to suspect a bad tranny or loose connection on one of the connections to a winding that makes the tranny act as less than 30 VA. I got a stable 70 volts on each independently, but it was climbing past 80 with the two connected together.
Thanks for checking. I am heading home now and will do some checking on my end. I am beginning to suspect a bad tranny or loose connection on one of the connections to a winding that makes the tranny act as less than 30 VA. I got a stable 70 volts on each independently, but it was climbing past 80 with the two connected together.
Ran through the tests and the problem went away. My best guess is a loose primary connection on one of the windings. I had pulled the connections to the AC to test the tranny and solder the parallel primary wires together before reinstalling. The problem went away. Add to this that I now get 78 V no load out of the + side instead of 70 V and I would have to conclude the problem was that only one primary winding was hooked up.
If it works........
If it works........
Sorry if I missed it somewhere but how is the attenuator coming along? I am about ready to mount everything in a case and would like to allow for this if possible.
Thanks, Terry
Thanks, Terry
Its coming along well, I will get some ordered quickly if I get enough people who say they want them. Response has been pretty low, so I was not sure if people really wanted them. If you want one please post or email me so I have an idea how many PCBs to order. Also, Brian and I may just go ahead and put up a pre-order page on our site to help get things rolling. The circuit is tested and ready to go.
Look here for more details:
http://www.diyaudio.com/forums/showthread.php?postid=856475#post856475
Cheers!
Russ
Look here for more details:
http://www.diyaudio.com/forums/showthread.php?postid=856475#post856475
Cheers!
Russ
Avel Trafos
So, I am ready to order the trafos from Avel, but am unsure how many people want them. I have had a few requests, but need to order at least 25 pairs, so I would like to get some idea how many people are interested.
The price would be around $30-$35 for a pair, which is:
1 - 30VA, dual 12V secondary, dual 115V primary
1 - 50VA, dual 30V secondary, dual 115V primary
One pair can power two X-Bosoz channels (Russ is doing this now), or you could get two pair for a full dual-mono setup.
They would be wired with the secondaries in series, for 60V and 24V.
As for shipping, I can a pair ship anywhere in the US for $6, and to most countries for $6. If your country cannot get USPS Global Priority deliveries, it will be a bit more, but not too much. Outside the US, I will always be sending them as a seperate package, even if you order them with a X-Bosoz kit, as it is the cheapest way to ship them. Inside the US, they would be counted as a second kit.
If you are interested, send me an email. If I can get 10 or so spoken for, I will order and start shipping.
So, I am ready to order the trafos from Avel, but am unsure how many people want them. I have had a few requests, but need to order at least 25 pairs, so I would like to get some idea how many people are interested.
The price would be around $30-$35 for a pair, which is:
1 - 30VA, dual 12V secondary, dual 115V primary
1 - 50VA, dual 30V secondary, dual 115V primary
One pair can power two X-Bosoz channels (Russ is doing this now), or you could get two pair for a full dual-mono setup.
They would be wired with the secondaries in series, for 60V and 24V.
As for shipping, I can a pair ship anywhere in the US for $6, and to most countries for $6. If your country cannot get USPS Global Priority deliveries, it will be a bit more, but not too much. Outside the US, I will always be sending them as a seperate package, even if you order them with a X-Bosoz kit, as it is the cheapest way to ship them. Inside the US, they would be counted as a second kit.
If you are interested, send me an email. If I can get 10 or so spoken for, I will order and start shipping.
Re: Avel Trafos
Hi Brian,
Forgive me if this has been covered but what are the dimentions of the trafos? I may be interested in saving the space and weight that the PE trafo takes up.
Thanks, Terry
BrianDonegan said:
Hi Brian,
Forgive me if this has been covered but what are the dimentions of the trafos? I may be interested in saving the space and weight that the PE trafo takes up.
Thanks, Terry
Russ White said:
Hi Russ,
Do I understand correctly that the attenuator will not give the ability to balance left and right channels?
How is everyone controling the volume of the XBOSOZ without using some type of attenuator?
Thanks, Terry
still4given said:
It is not currently designed to do so no, but it would be easy enough to design a new controller board which could control two relay PCBs independantly allowing you to change L/R balance.
With the current controller it works exactly like an ordinary stepped attenuator except that it both has a constant output impedance and is logarithmic. Two relay PCBs are daisy chained (share same control lines) for balanced signal opertaion.
It is both easier to build and should be much less expensive than any rotory stepped attenuator you could buy or build.
The output impedance I am using right now is 2.2K which is working quite well on the output of my XBOSOZ.
Cheers!
Russ
Avel dimensions...
Y236207
Y236102
On this page
http://avellindberg.com/transformers/y23_range_specs.htm
Y236207
Y236102
On this page
http://avellindberg.com/transformers/y23_range_specs.htm