Pocket Amp 2

[hciman77]

Quote:

Originally Posted by marcus521 how big are the cmoys? like a credit card?

It depends who builds them, The CMOY is a design not a kit. Many builders put them in Altoid-mint-type metal cases either rectangular or round, some use hammond cases and others use well other cases.

Go to eBay and do a search for "headphone amplifier" and you will see some examples of CMOYs.

They are normally quite small but that rather depends on how you define small. In some incarnations the biggest interior space is taken by the batteries. the actual op-amp can be smaller than a fingernail (in 2 dimensions anyway).

 

[Earwax]

CMOYs are typically cased in altoids mint tin sized boxes. But there's really no standard for CMOY cases. Just as there's no real standard for the parts used.
I've built about half a dozen cmoys and done a fair bit of tweaking and experimenting to fine tune the sound and there is quite a bit a variation possible.

For the purpose of comparison, I sent Hciman what I think is a pretty standard cmoy, built mostly according to Tangent's parts list with a few tweaks that the ebay cmoy builders often use, like the OPA2227 opamp and .22uf polypro input caps.

 

[marcus521]

Ok, which is the smallest, the headsave go-vibe or the cmoy in altoids mint tin cases?

 

[hciman77]

From Norm's website (Go-Vibe)
Very compact custom Hammond ABS case (3.6”L x 2.6”W x 1.1”H)


How big is an Altoids tin?
3 1/2"W x 2 1/8"D x 3/4"H

Though I would not use size as my main criteria for making a choice between these 2, especially as there is not that much difference.