From Nav Guy's O2 Details Blog, "There have been several suggesting higher voltage supply rails for various reasons. Some have dredged up rare discontinued headphones that need more than 7 Vrms to hit 115 dB SPL"
Are K240M's rare? Oh well, I guess I'm beat!
Are K240M's rare? Oh well, I guess I'm beat!
I could not get the Import BOM to work on a Linux computer. Instead I read the XLS file with Gnumeric, swapped columns to show part number followed by quantity and saved as a CSV file. Then I used a text editor to finalize for Mouser's format so I could copy-and-paste into the Mouser web page. No sweat... yeah sure.
Planning on adding this to the o2, im not going to use battery so if necessary im planning on cutting the board to make it fit.
Hmm.. I used OpenOffice in Ubuntu, and just cut and pasted the two columns out of the file as is, and it worked for me..
Well, rare might be debatable, but discontinued? yes. The K240MkII which replaces it (or the K240Studio) both have an impedance of 55ohms, which is realistic with the O2.
From AKG's website, under the K240M details: "600-ohm impedance for special studio applications". So it sounds like they are setup to be used with electronics that are less likely to be found outside of a studio...
Actually, I just discovered that My K601's at 120 ohms might be the highest impedance AKGs around now, and for some odd reason can't find them on the AKG site(not even in discontinued models)... 😱
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Gain Question...
If I feed the o2 with my AMB Gamma2, what is the highest gain I should use?
The output level of the gamma2 is 1.4Vrms at 0dBFS
Thanks for your help!
If I feed the o2 with my AMB Gamma2, what is the highest gain I should use?
The output level of the gamma2 is 1.4Vrms at 0dBFS
Thanks for your help!
From blog:
Maximum Gain = 7 / Vin(max) and on batteries it’s 4.5 / Vin(max)
On a totally separate note, I have just noticed I wired my TRS jack completely backwards: I wired the left channel on the board to ground on the socket, the right channel to the left channel on the socket and board ground to the left channel. I am even more confused by the fact that I have been listening to it and both channels seemed fine
Maximum Gain = 7 / Vin(max) and on batteries it’s 4.5 / Vin(max)
On a totally separate note, I have just noticed I wired my TRS jack completely backwards: I wired the left channel on the board to ground on the socket, the right channel to the left channel on the socket and board ground to the left channel. I am even more confused by the fact that I have been listening to it and both channels seemed fine
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It's disappointing that, with my current headphones, I can't take advantage of what promises to be a great portable amp in such well presented diy package. Looking at "The Wire", I think I'd be out of my depth, there (ie; SMT). I'll go ahead with the O2 in the meantime, thanks MrSlim 🙂
I wouldn't worry too much. I found a Clip+ to be quite adequate for my 600 ohm HD420SLs, which should be no more than 3 or 4 dB more sensitive than the venerable K240M. And that was on dynamic classical tracks. An O2's maximum output level is about 20 dB higher than the wee Clip+'s.
I'm waiting for my parts to arrive, imagining how it would be - assembling the O2 (I'm a noob in it), and I can't help but remember the best circuit diagramm EVER. Take a look, you won't regret it.
Sorry for OT 🙂
Sorry for OT 🙂
Hi guys,
What's the deal with batteries, then? Anyone found a good source?
I can get them for £1.80 each - would it be worth me stocking up?
What's the deal with batteries, then? Anyone found a good source?
I can get them for £1.80 each - would it be worth me stocking up?
I got mine here: NiMH Batteries Combo, Compact AA AAA Charger Kits items in All-Battery Center store on eBay! but I think you've got me beat on price.
Hey RocketScientist.
Have you come any further with the audio-widget guys on the DAC?
I have bought the 9023 DAC to see if I can help the community to tweak it to be an all purpose one at least up to 24/96 if it shows that we are good doing what we are doing 24/192 shouldn't be a problem.
Brgds
Have you come any further with the audio-widget guys on the DAC?
I have bought the 9023 DAC to see if I can help the community to tweak it to be an all purpose one at least up to 24/96 if it shows that we are good doing what we are doing 24/192 shouldn't be a problem.
Brgds
From AKG's start page, make a left turn at Personal Audio, continue to Home and there be the K601's.
I've been thinking about this since I posted that and I really don't have the time at the moment to organise it. The batteries are on special offer until close of business on Monday so if someone else wants to jump in and buy a bunch you have until then.
Sorry I can't be of more help!
(I can't remember if I have posted the source already but it is: Rechargeable NiMH batteries Hi Watt AA, AAA, C cell, D cell PP3 batteries)