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mouz

Interest Check: AMB's Y1 DAC

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ok guys...I am a little confuse about the enclosure now? What am I suppose to get it from now? or some one if organizing a group and cut for the front n rear panel?

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there are THREE different group buys.

1 for the PCB and components from AMB.

1 for the enclosure.

1 for the laser cut panels (which IIRC is acrylic? i think).

 

ok guys. just a suggestion.

unless you guys are going to have one person buy all the components together and then split them. its more convenient to buy all the components yourself from farnell together with the enclosure, thats because if your order is over $30 shipping is waived. unless you wanna save $2 bucks and go through the hassle.

Edited by gene83

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bro, one of those interested backed out so left 4 guys, doubt we can get that discount for the enclosures now man...

 

I may want to order 2 enclosure cause I still have one spare Mini3 board to build so if anyone interested can leave the name first and I'll consolidate.

 

Bro, placing ur order for the PCB set? :)

 

I'll take one set of pcb + all updated components that you have listed. Pardon my laziness for not pasting the list here again :grin:

 

 

ok guys. just a suggestion.

unless you guys are going to have one person buy all the components together and then split them. its more convenient to buy all the components yourself from farnell together with the enclosure, thats because if your order is over $30 shipping is waived. unless you wanna save $2 bucks and go through the hassle.

 

Agree and I don't mind to order all the components + enclosure from farnell and split but I need help on getting the complete BOM. Really have no time to check and compile the BOM myself.

 

Also mouz already mentioned that there are parts that you need to order in qty of 10 and it's a waste of money for those who may not need the parts in the near future. Although some parts are not expensive even in qty of 10...well we still have time until mouz order the pcb :thumbup::whistle:

 

 

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there are THREE different group buys.

1 for the PCB and components from AMB.

1 for the enclosure.

1 for the laser cut panels (which IIRC is acrylic? i think).

 

ok guys. just a suggestion.

unless you guys are going to have one person buy all the components together and then split them. its more convenient to buy all the components yourself from farnell together with the enclosure, thats because if your order is over $30 shipping is waived. unless you wanna save $2 bucks and go through the hassle.

 

 

Ok,,I think i m in for PCB n components and the laser cut panel together with mouz...so who is do the enclosure?

 

Whoever is doing the group buy for the enclosure just add me in....

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Ok lah, seems like almost all the guys interested are here already. Will close the group buy on Sunday night. Give those guys who might be busy on weekdays a chance to look over the weekend. U guys alright with this?

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Ok lah, seems like almost all the guys interested are here already. Will close the group buy on Sunday night. Give those guys who might be busy on weekdays a chance to look over the weekend. U guys alright with this?

 

no problem for me....

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Update from AMB, he has recommended a change of value for R20D to 47kohms

http://www.head-fi.org/forums/5291175-post328.html

After some testing, MisterX and I have decided to change the value of the R20D resistor. It was originally 75 ohms, the new value is 47K ohms. If you have already built a γ1 with the old value, it is an optional (but recommended) update.

 

You should hopefully have some spare 47K resistors because the Panasonic, Xicon and Multicomp resistors from Digikey, Mouser and Farnell, respectively, are sold in multiples of 10.

 

Background:

 

This resistor terminates the CS8416's RXP0 input, which is used for the S/PDIF datastream from the PCM2707's DOUT pin. Originally it was thought that 75 ohms was the appropriate termination for this line, but the PCM2707's DOUT pin is not "standard" S/PDIF. It's an unbuffered 3.3Vpp TTL output, not intended to drive a long transmission line or a low impedance load such as a 75 ohm resistor. At 75 ohms, the "3.3Vpp" output got loaded down to around 1Vpp. This is still more than enough voltage to drive the CS8416's RXP0 input (which has an VIH threshold of 150mV typ.), but nevertheless it makes the PCM2707's DOUT work harder than it should (1Vpp into 75 ohms is about 13mA of output current).

 

Since the distance between the PCM2707 and the CS8416 is short and doesn't qualify as a transmission line, there is no need for line termination. However, a high value resistor helps to keep the S/PDIF pulse waveform clean. We settled on 47K as the new resistor value because does not load the PCM2707 down (the output voltage is now ~3.3Vpp and output current is now only 70uA), gives good S/PDIF pulse waveforms on the scope, and is a value that you should already have.

 

Note that this change should reduce the amount of fast current pulses drawn by the PCM2707 and result in a cleaner 3.3V supply rail on the USB board. I don't expect it to actually improve the "sound" or the customary metrics such as noise floor or distortion, but it is a good, simple update, so I encourage you all to make this change.

Edited by mouz

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Sorry guys, a bit busy due to CNY. Items have been ordered, probably will arrive in about 10 days if nothing screws up.

 

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bro...resistors and torx order placed with Farnell. All the parts that I order will be delivered probably by end of next week. So now back to you to get the major component in :rclxms::smoke:

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You guys want the PCB first? I can meet you all along the MRT line between Jurong East and Tanah Merah on any weekday 1730-1800hrs. I can foresee that some parts will take some time as most of their status is still pending. Can take and do some SOIC soldering first while waiting for the rest to come in...

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You guys want the PCB first? I can meet you all along the MRT line between Jurong East and Tanah Merah on any weekday 1730-1800hrs. I can foresee that some parts will take some time as most of their status is still pending. Can take and do some SOIC soldering first while waiting for the rest to come in...

 

 

I prefer to get everything at 1 shot...don't mind..

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