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O2 amp parts GB, EU

Here we go: After timpert suggested to look for the O2 parts in the EU, we found a couple of parts were difficult to source.
RocketScientist then revised the BOM to use only parts available directly from Mouser.
And since everything seems golden now, we can go ahead with a group buy for the O2 parts.

Since nobody else stopped me from doing so, I would like to offer to host this GB.

As I dont have an established reputation in this forum, I would of course be willing to send my personal details, eBay Name or other forum refernces to an established DIYaudio-member or two.


PARTS:
I used RocketScientists O2-BOM as-is without modifications or going for any of the listed alternatives.
This means there are NO 9V batteries, NO wall transformer, NO aluminum enclosure and also NO low-power Op Amps, "Desktop O2"-Parts, or solder/wick included in the kits.
However, all gain resistors are included. These cost between 1€ and 2€ total and it greatly simplifies the bagging/sorting process for me if I don't have to match resistors to Names...


UPGRADES / EXTRAS:
If desired, you can add parts from Mouser to your order of an O2 kit.
That means if you do want to use the low-power OpAmps, build a desktop version of the O2 or anything of the sort, that is possible.
Simply state the number of O2 kits you would like and add the MOUSER part numbers and the desired quantities.
Please don't assume any volume discounts other than those coming from your own parts, also I can not guarantee availability of any extras at the time I place the order with Mouser.
Also, if your parts are large or heavy, the shipping costs from me to you may increase.

PRICE:
Currently, the Mouser order adds up to the following prices:
Quantity: 1 - 41.72€ / kit (incl shipping)
Quantity: 10 - 20.72€ / kit (free shipping)
Quantity: 20 - 19.63€ / kit (free shipping)
Qunatity: 50 - 16.37€ / kit (free shipping)
Quantity: 100 - 15.02€ / kit (free shipping)
As you can see, the sweet spots are 10 and 100 kits. I expect more than 10 orders, but less than 100 (happy to be proven wrong btw).

SHIPPING:
Most countries (EU at least) should be covered by the 3.45€ rate of the Deutsche Post / DHL .
(50 to 500 grams, priority air mail, cushioned envelope possible, shipment of goods is allowed)
Additional insurance is available (2.05€ base rate + 1.55€ per 100€ of value) -> +3.55€ for most small quantities.

Additionally, I will need to buy envelopes and ESD-bags...
My current estimate for these is 1€ per order for envelopes and ESD bags

Long story short: We will probably end up with around 20 to 50 kits.
Everything included, I expect the total price to be 27€ for one kit + 22€ per additional kit.
This is subject to change as Mouser prices may go up or down and I have not yet bought the envelopes or ESD-bags...

PAYMENT:
Payment is possible via PayPal, bank transfer or cash in an envelope if absolutely necessary.

My Questions for you:
1. Do you want to order the enclosures too? That would increase shipping costs from me to you but may end up saving you money.
2. Batteries? With or without? What brand/dealer would you like/recommend?
3. Anything else I may have missed?

Gentlemen, start your engines!
 

lenconian

Member
2011-05-03 8:23 pm
Allright then, I'm in for one kit. I'd also like to have:

Quantity Item Mouser Parts Number
1 Female RCA Jack Gold Red Insulator 568-NYS367-2
1 Female RCA Jack Gold White Insulator 568-NYS367-9
1 Vertical Mount 1/4" 3 Conductor Phone Jack 568-NJ3FD-V
1 wall transformer 553-WAU12-200

Personally, I don't need the batteries or enclosure.
One thing we need to discuss ( I guess ) is which volume pot are we going to order?

Thanks for putting up the group buy by the way, hopefully we'll see a lot of participation:cheers:

Oh and on a sidenote. I do find the original, plasticky volume button a bit ugly. I have not had a look at other possibilities yet, but if a metal one would be just a tiny bit more expensive, maybe we could settle for that?
 
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I want two kits! And one enclosure, should you decide on buying those too.

By the way, thanks for picking this up.

One suggestion: don't include batteries, as they are very common and preferences may vary. This saves you some hassle and shipping cost. Ebay is full of them, for about half what they cost in most electronics stores. That is, if you don't care for the fancy label brands. Particularly good deals seem to be available from the UK and Germany. I just purchased these:

4 x 9V 250mAh NiMH RECHARGEABLE BATTERIES LONG LIFE | eBay
 
Well, if the cases are indeed wanted badly, I will see if or where I can find decent cases.
Any input or experiences with vendors for the cases are appreciated.

@Lenconian: I have selected the RK09712200MC Alps pot.
Its specifications are identical to the RK09712200HA pot, only shaft length is 15mm instead of 20mm.
It is my understanding that the new PCB design accomodates both 15mm and 20mm parts.
If absolutely necessary, I will make it an option to replace the pot, but I'd prefer to have the base-kit identical for everybody.

As for the metal knob: My local dealer had one nice black aluminum knob with a red line.
I bought it for 12,99€ ^^
If you find a knob from Mouser that you like better, you can just order it via the "extras"...

@timpert: If there is enough interest, I'll be happy to throw the batteries in the mix. The 500g shipping limit should suffice.
Mouser only supplies lousy 9V blocks, so they are not an option.
For myself, I will most likely go with two 7x (8.4V) Sanyo Eneloop XX packs, but thats just me.
If there is no common preference for the batts, I'll not include them as they are available locally for everybody.
 

lenconian

Member
2011-05-03 8:23 pm
I guess a seperate "case group buy" might actually make sense here.

@ Jokener: The Alps pot is quite alright, no worries. And 13€ is quite a lot to ask for a metal knob, so I guess I'm gonna stick with the plastic variant for now and maybe DIY a nice wooden one in time.
 
About the case:
@Brian: In the US, MrSlim is offering a full-service O2.
You should be able to source an Allied Electronics Aluminum case directly from him.

@all: I could not find a better case supplier than Allied Electronics.
I have done a custom case design, however.
It's a 2-part enclosure in the shape of two "U"-s (Left/Bottom/Right + Back/Top/Front).
Manufacturing WILL be quite expensive, since it's lasercut and bent from Stainless Steel.
(I'm expecting 25+€ for my design, manufactured at a shop I know.)

So there are basically three options:
1) I offer my design for sale. Wasn't planning on doing it, but I might as well.
This would require a prototype by next week, so I can take pictures and you can decide.
2) I order from Allied Electronics. Cases should be ~15€ each (11$+shipping+import tax)
3) We exclude the cases from this groupbuy.

What's the opinion on this?
 
Jokener, thanks so much for taking this on! I have a few comments/suggestions:

I would strongly urge holding off on buying the components until the PC boards arrive, and at least Oliver has built up an O2 with the new PC board. And, by then, hopefully a few other O2's will also be built up and used by others. I think many are moving too fast for a brand new design and I am especially worried about the latest PC board files as I have not built a prototype of the new board. For example, the 15mm volume control pots should work but I have not tested it. And people might discover other problems so some may change their mind about the O2.

Is Farnell Europe a better source for the enclosure than Allied in the USA? They are 12 Euro and you won't pay import tax and less in shipping: BOX ENCLOSURES|B2-080BK|GEHAEUSE,ALUMINIUM,SCHWARZ, 109X30X80MM | Farnell Deutschland

I agree leave the batteries out. eBay is best.

The AC wall transformer is perhaps one of the more difficult items to source. Perhaps the one from Farnell could be purchased with the enclosures above? In the comments to the O2 Details article there was some discussion about very high shipping costs, minimum order sizes, etc. to obtain the transformer. So that might be a very good Group Buy item?

Has anyone looked into quantity discounts from Schaeffer AG for the front panel? (The panel design is also unproven but hopefully will be tested soon). The problem is they would all be the same color and lettering but it might be a nice option.

It's also possible, for a large order, you might save some money buying some parts from TTI, RS Components, Farnell, etc. instead of Mouser.

The most critical things for the design that you almost have to get from Mouser (or TTI) are:

- Eagle battery clips
- NJM4556
- STX3120 3.5mm Jacks (you should ask for color preferences on these)
- PN22SJ Switch
- Switch button
- MV5764.MP4B LED
- 2.2 uF capacitors (Farnell at least doesn't have a direct substitute)

Everything else is fairly generic and should not be a problem getting elsewhere.

I'm looking forward to pictures of your custom case!

Hopefully leave some nice profit for yourself and perhaps encourage extra donations with payments. Group buys seem to be LOTS of work! Thanks again for taking on the challenge. :)
 
@igor: Right now it is just a CAD file, since I dont have any sheetmetal at hand.
And there are two important deadlines coming up at work next week, monday and saturday. After that I have nothing but time...
So right now I'm thinking next saturday after work I'll get crackin' on manufacturing my own case design prototype.
I'll post the CAD pictures soon, but a photo will have to wait.

@Jerom:
Personally, I would prefer not having to build cases for others. At least not a design I have never done before.
I have built formula racecars and I disassemble an engine and adjust valve timings at 2:30 in the morning, no problem.
But it is the same situation for me as it is for RocketScientist: Unproven design... something you learn from racing, the hard way...

@Amrad:
You're correct, 2.05+1.55=3.60. I didn't double-check the postage options...
But now I did and its 2.05€ + 1.50€, so we get back to the 3.55€ I quoted before.

@RocketScientist:
I won't order within the next week or two for exactly those reasons.
But I want to get the obvious obstacles out of the way as soon as possible, so that we can start when everything else is ready.
The Farnell Cases look great. So unless anything else comes up, I would offer those.
(I'll just have to figure out an appropriate price, with shipping costs and all.)

Somehow, the AC wall transformer looks like a fairly small challenge.
There are plenty of shops that sell them, including Farnell etc.
If there is enough interest, I can add them to the offering with no problem at all.
It would increase shipping costs, but thats just the way it is.
Right now there is the Mouser unit and if we decide on the Farnell cases, they have them too.

If at all possible, I would like to stay with Mouser as the sole or main supplier next to Farnell.
At a total of 15€ in parts that can be influenced, there is just not enough money to be saved to justify another vendor...
It might end up saving everybody a dime, maybe 40 cents... And it might delay things...


But, in the spirit of you designing this little beast at no charge, I won't try to make a huge profit on the GB.
I'll make sure not to charge too little, but I am not trying to make at least X Euros per hour I spend on it.
Of course me and my girlfriend (she'll help with the bagging and the tagging) would appreciate it if someone threw in a little extra, but thats not mandatory.

Anyway, with all your orders so far, we are at 12 kits (including my own 3).
That means the 27€/22€ rate (first/additional) for the kits should work out if we find a couple more buyers in the next two weeks.
So if nothing goes south with the boards, we're almost set to go.

And yes, it will be quite a lot of work and repetetive processes to sort and bag everything.
But a couple of years back I had a summer job folding paper protectors that go in between layers of rolled sheetmetal parts at a factory.
2500 protectors in 8 hours... Repetetive processes? I can do that :)
 
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