That looks great, really makes me want to get mine done.
You are using one relay for the delay and one for the input, Tea-Bag do you have one of the input relays pulled closed when you get the chatter? Just a random thought that occurred to me. grufti and crt have Mezmerize. I know you do too but did not see anything in your photos and I think I recall you saying you have not listened... kannan_s has the chatter and only one relay so it leads me to that question.
You are using one relay for the delay and one for the input, Tea-Bag do you have one of the input relays pulled closed when you get the chatter? Just a random thought that occurred to me. grufti and crt have Mezmerize. I know you do too but did not see anything in your photos and I think I recall you saying you have not listened... kannan_s has the chatter and only one relay so it leads me to that question.
I closed the relays per Salas' advice.
The noise occured either way, with two different NPN's.
The cap took the audible noise away.
I still have not listened. Will try to wire it up soon for a listen. I trust other ears than my own as well.
What connectors are you using for the input output wires (3 pins??) I forgot to order those. They look helpful. Do you have any part #'s for those?
Oh well, there goes that idea... thought load may have come into the equation.
I got them off the BOM that korben69 provided.
538-22-01-3037 3 hole
538-22-28-0030 3 pin
538-08-50-0114 crimp on for 3 & 7 hole
538-22-23-2071 7 pin
538-22-01-3077 7 hole
All from Mouser and are Mouser part numbers. Can't wait to try them, never used them before.
I got them off the BOM that korben69 provided.
538-22-01-3037 3 hole
538-22-28-0030 3 pin
538-08-50-0114 crimp on for 3 & 7 hole
538-22-23-2071 7 pin
538-22-01-3077 7 hole
All from Mouser and are Mouser part numbers. Can't wait to try them, never used them before.
Tea-Bag misses the power on led VS Grufti's. Thats all difference I see.
The BC550 or 546 pulls only one relay, the others are closing to earth via the input switch. Now if you tell me that the 5mA current of the power on led keeps the 7812 running and is not surprised by the sudden inductive load...Don't know. On the other hand, Kannan's has the power on led but not 2 relays pulled. Silly 7812s ?
Salas, your latest suspicion might just be spot on. It might be worth trying to find out if the 7812 [7805] gets unhappy in some of these circumstances. Who knows, two power on LED's might be better than one.
I crawled a little closer to my build and took two more photos.
I crawled a little closer to my build and took two more photos.
Attachments
So.... How mad am I? I just got my resistor order, all my nice Takmans are there and the prps for the rest are there but instead of 68R they sent 68k!!! I double checked my order and I definitely ordered 68R. Darn, darn, darn.
You don't need quality resistors for the 68R//68R position. They just set the DC current. Any decent metal film will do. What you got in your drawer? Do you have any 33R 0.5-1W? Or 6x 100R 1/4W? There are pads for 3X100 per side. We have given some play space there with Crt.
That's good news, I'll see what I can dig up. Looks like Radio Shack, a local store, should carry either the 68r or 100r. I will be able to pick some up at lunchtime. I'll be listening to this thing tomorrow!!
No worries. Pick 6X100R 1/4W from RS local store. Later on you can get your PRPs for aesthetic continuity with the other PRPs against the black PCB. For sourcing the DCB1, their total dissipation will be around 130mW per side. I advise 0.5W to 1W total capacity, bcs I have found that resistors in general, better be at least 3X dissipation safe so to last for ever.
If others gonna use the regs part only, those resistors will change for much more current, and sinks or metal floor Mosfet mounting will be a must.
If others gonna use the regs part only, those resistors will change for much more current, and sinks or metal floor Mosfet mounting will be a must.
In what system and against what as installed previously in the line position? Let's see if you gonna get the chatter too, so don't forget to pick one 150nF ceramic too.
It will be in place of a conrad johnson PV7a, although right now there is a pair Diamante that I built a few weeks ago. It will be connected to a pair of MyRefC amps that go into NHT Super Ones. It is in my office at work and as of now provides a nice detailed sound with a decent sound stage. The speakers are almost near-field as they are only about 4-5 feet from the listening position.
I know it is not much. But it is my hope to be building a nice system around this "DCB1"
For source I use my computer with lossless files played on foobar with ASIO4all, spdif out to a Gamma 1 DAC or CAL Audio Labs Alpha DAC I also use a CAL Audio Delta transport for CD but find I use the computer more.
I should have the right caps in my bin, I hope not to have to use them but am prepared if I need to.
I know it is not much. But it is my hope to be building a nice system around this "DCB1"
For source I use my computer with lossless files played on foobar with ASIO4all, spdif out to a Gamma 1 DAC or CAL Audio Labs Alpha DAC I also use a CAL Audio Delta transport for CD but find I use the computer more.
I should have the right caps in my bin, I hope not to have to use them but am prepared if I need to.
Enough of an audio arsenal to check against. Your evaluation will be interesting. Let it run signal for some hours before evaluation starts, even with the main amp off. It will be 80% broken in after 48h running. The full on test isn't only break in, its part of the proto reliability check, since it does not sport sinks as a must. Lets see it does not fail double Le Mans. Good luck with your build.
My Mezmerize has now played 48 hours continuous music without a hitch.
I had pulled the plug on it a couple of times early on [no switch yet] and it handled that just fine. I have now pulled the plug again after the first two days and everything still behaves as designed.
I had pulled the plug on it a couple of times early on [no switch yet] and it handled that just fine. I have now pulled the plug again after the first two days and everything still behaves as designed.
That's great. DC offset still minimal? How do you feel about the performance after 48h? Anything new to add on your initial subjective report?
I'll write more about the music later. DC offset on the output is further reduced. It is now in the 0.1 - 0.3mV range.
Still no trouble with the relays.
Nothing is hot. There was never any smoke. I am extremely happy and excited.
This first one will get another volume pot or switch. I'll get around to the motorized volume control / remote input switching later on. I have other resistors to try in future incarnations as well. Just building a decent looking enclosure is always such a hassle.
What a great design!
Still no trouble with the relays.
Nothing is hot. There was never any smoke. I am extremely happy and excited.
This first one will get another volume pot or switch. I'll get around to the motorized volume control / remote input switching later on. I have other resistors to try in future incarnations as well. Just building a decent looking enclosure is always such a hassle.
What a great design!
I have started a shared spreadsheet to start tracking a potential order list again for the DC B1. Pricing will be determined mostly by demand, and if there are any other changes. I don't plan on ordering these until several more people are up and listening to the beta production boards.
http://spreadsheets.google.com/ccc?key=0An3nVM43ZbQndHJSMVNSLVBwbVFUSEh5cXI3WnpDRnc&hl=en
This will at least temporarily replace the Wiki. Lets see how it works.
Tea-Bag
http://spreadsheets.google.com/ccc?key=0An3nVM43ZbQndHJSMVNSLVBwbVFUSEh5cXI3WnpDRnc&hl=en
This will at least temporarily replace the Wiki. Lets see how it works.
Tea-Bag