justin

The past couple years just before the CanJam I've placed an order for ~10 CDs at Acoustic Sounds to have some more high quality stuff to show off the gear. And it never fails that Norah Jones is still the only CD anyone wants to put in. So, I'm looking for some suggestions this time. Really well recorded stuff in a variety of genres, must be good music and not just impressive sound, and SACD is a major plus

PCM1704 should have a power dissipation of 175mW. A SOIC-20 package will heat up about 200F/watt. That's an increase of 35F so if you have a room temperature of 75F, and the PCM1704 is sitting in open air, it would be 110F. It's reasonable if you have an enclosed case and other components increasing the ambient temperature inside the case that you would get 127F

MOTs that weren't asked to organize the event?

can MOTs go?

We could just make portable amps the same size as iPod Shuffles. To save money, we can just buy the shuffles and disable the DAP functionality and add a line-in jack

Heh. Well that provides some valuable info. It means his battery is much smaller than the one I am using - so he can't be using the same volume control or it would never get the 10000 hour battery life required. It also means it will be push buttons or toggle switches, which I don't want to use mostly for 2 reasons: can't tell where the volume is without a display, and it loses the analog feel. I could probably shave off a couple hundredths of an inch by going with a weaker & harder to produce extrusion, but anymore than that and I'd have to start reducing the size of the battery and every mm will probably take 10 hours off the battery life. Why dont you ask how many steps and how much attenuation Looking at diameters of 3.5mm plugs, one of the thinnest is the Neutrik at 0.35". Grado 1/4 to 1/8" adapters are 0.435", and ALO uses some that are up to 0.5" diameter. Which means any amp that is thinner than the plug is potentially going to have issues stacking with a DAP.

yeah, in that case, i guess im mostly interested in seeing the measurements.

is this online? if not, can you post hte full review?

you just need a Nugget Audio name tag

UE4 custom IEMs announced, and already reviewed by Jude, who lately is on a streak of reviewing $399, dual driver. only available in clear. 108dB/mW sensitivity, low for a custom IEM

Head-Fi: Covering Headphones, Earphones and Portable Audio - View Single Post - Grado construction

I think there are already enough volume control kits available. This one could be made very small but that may not matter for DIY home amps

it would be nice if it could work as a USB host, and then an external DAC could be used. will never happen though

It's a variable gain amplifier, so it already has plenty of gain switches Each step is .5dB. Max gain is 6x -- so you can max the output of this amplifier with a source output as low as 0.25Vrms.

wont matter, it would be useless to add a gain switch

the channel matching is better than 0.1dB. A gain switch would be redundant

It has as much power as most other lithium powered amps. The 'regular' Pico runs on a 2-cell, 8.4V battery, but that's unusual. So, its not specifically for IEMs, but if it can be the first choice of anyone with IEMs, I think I can live with that. A lot of the idea of this amp is to make a portable for people who aren't interested in portables because they are too bulky and offer little or no improvement. This solves those problems by being thin and offering a range of volume adjustment and precision left/right matching that you can't get from a DAP. Also, some IEMs like the Livewires and Westone ES3X are unusable from many DAPs/phones due to the amount of hiss from their headphone jacks.

Edwood came through with another fantastic rendering, this time of the Pico Slim

i'll stick with my 110dB attenuation. 60dB, 70dB attenuation, those are listening levels with some IEMs and some source output levels.

Are there specs on max attenuation and channel matching? I know a thumbwheel would work as good as anything else, but it lacks the visual appeal thats needed. The Iq of the Pico Slim is 12mA so a few mA is significant

I've never heard of that before. I just looked at it, I doubt it would fit in this size enclosure and the current use is probably too high. I could have used a thumb wheel, but those have only been used in much cheaper portable amps (like the Airhead). Hard to convince someone to spend up to $400 on an amp with a thumb wheel, even if its just being used for a digital volume control

Those kind of chips require a microcontroller and a 5V supply, so I think they're unlikely to be the ones used here. There are a few that will work with pushbuttons/toggle switches on 3V, no uC needed, so that seems most likely. But they're limited to 32 or 64 steps and don't offer more attenuation than a typical small volume pot

on head-case, why not.. HeadAmp Audio Electronics (Pico Upsampling USB DAC Pre-Order)

I haven't given out details on what I am using yet. At best, he can be using the same thing that I am, because nothing better exists. I went with a rotary pot/knob interface for it, although anything could be used - rotary encoder, push buttons, toggle switch, thumb wheel...because I feel a lot of hand holding is going to be needed to get people comfortable with the words 'digital volume control'.