[AdamWill]

so the head-fi wallet warnings are definitely coming true for me...two pairs of cans since I joined and now I bought an amp, sigh. I'm making myself a new desktop PC (I currently have a monitor sitting on top of my HTPC and use it as a desktop while sitting on my bed staring down at the monitor, which is horrible from both the aesthetic and the ergonomic viewpoint...) and I figured I'll try and make it into a half-decent audio station, so I'll be installing an AV710 (no emus for me, I run Linux) and using my SR80s, I'll use my Eggos for portable. So it became clear from the computers forum I'd be needing an amp out of the AV710, so I hit eBay and decided on the Twinstarr Black. I have no idea about the technology of amps, but the mumbo-jumbo looked convincing, the feedback's good, it's a very cute little box and there were no 'DON'T BUY ANYTHING FROM TWINSTARR!' threads here so I figured it was safe. It wound up costing $110, for which I guess I could just about have got an entry-level Pimeta second hand, but it seems this is near the top of the cmoy design line in any case, and it'll be nice to be able to use it portably if necessary. I'll definitely post impressions of it here when it arrives.

Just a couple of questions to go along with the purchase, to do with power. Running it off disposable 9V batteries for home use seems like a terrible waste, so...would it be possible to run it off rechargeable 9Vs? Or alternatively, would there be a relatively simple (i.e., preferably not involving a soldering iron) way to run it out of a wall socket?

Oh, and one final question; if I decided to upgrade phones at some point, would Linux PC -> AV710 -> Twinstarr Black be a good enough setup to do justice to, say, a pair of SR-225s? Not necessarily draw out their absolute best, just give them a decent chance and make them clearly better than my SR80s.

Specs on the amp here: http://www.twinstarr.com/twinstarr_black_apheared.htm

Thanks!

 

[aznsensazian]

According to the specs, its a nice little amp. An apheared 47 design is more than enough for your grados. I would buy some different opAmps for opAmp rolling though. You may not like NJR4556 opAmp sound. Try the opa 2227 or ad8620 opAmps. These can be found on the digikey site. Enjoy your new amp and make sure to break it in nicely.

 

[atx]

Quote:

It wound up costing $110, for which I guess I could just about have got an entry-level Pimeta second hand, but it seems this is near the top of the cmoy design line in any case, and it'll be nice to be able to use it portably if necessary. I'll definitely post impressions of it here when it arrives.

$110 on ebay??? That is their retail price. You could've just gone to their website directly and order without going through the bids. I was thinking about buying this myself, but whenever I tried, someone always outbids me. I just couldn't shell out more than $60 for opamps that cost 50 cents.

Quote:

Running it off disposable 9V batteries for home use seems like a terrible waste, so...would it be possible to run it off rechargeable 9Vs?

Maha Powerex rechargeable batteries are true 9.6V, so you can use that without any problems. Other rechargeable brands are actually 8.4V or 9.2V.
See thomasdistributing.com for more info.


Quote:

if I decided to upgrade phones at some point, would Linux PC -> AV710 -> Twinstarr Black be a good enough setup to do justice to, say, a pair of SR-225s?

Different amps sound different. Personally, I think Grados sound fine without an amp. While an amp definitely makes them sound better, they do justice on their own unamped. I think it's a matter of personal preference on what you find lacking on your Grados, and get an amp based on that.

Anyway, let me/us know how the SR80 sounds with your new amp.

 

[AdamWill]

sorry, 110 was Canadian dollars. US$81, $5 shipping. What's the thing with the opamps, in more detail? oh, and yeah, the sr80s sound fine unamped, especially out of my Neuros...but apparently anything sounds bad unamped straight out of the the AV710, you really need an amp even for Grados.

 

[atx]

Quote:

What's the thing with the opamps, in more detail?

You may want to try different ones, since they each sound different. Although they must have chosen NJR4556 for a reason. Other chips may require higher voltage and the 1 9V power supply may not be enough or optimal, since you need 2 dual opamp.

 

[AdamWill]

azn seemed to imply there was something seriously odd / wrong with these ones, though, at least that's how it read to me.

thanks for the battery page, useful stuff! another $40 for battery and charger then, sigh

 

[atx]

Quote:

azn seemed to imply there was something seriously odd / wrong with these ones, though, at least that's how it read to me.

The NJR4556 is the same opamp that's being used in Grado's RA-1 amplifier which costs $300, so I wouldn't worry about it.

Some may not like how it sounds, but its all about personal taste.

 

[aznsensazian]

Yeah, its definitely a matter of personal taste. I was just giving you options if you didnt necessarily like the sound. I think the opa2227 uses less current than the NJR4556. Since your opAmps is socketed, this is a nice option. Its a good way to try out different flavors of sound to your liking for less and not have to buy different amps IMO.

 

[Necros]

Got one here at the moment..I think it's a little bit too clean sounding, for what of a better word...at least with RS-1's. My iriver output isn't as clear, but a bit more "musical" With Sennheiser 535 the Twinstar Black makes the sound a bit more forward (535 are a bit boring sounding)

Retail price is $110 American Dollars, not Canadian (even though based in Canada), as from their website. You're getting confused with their Blue (standard CMOY)

So what differences in sound quality would replacing opamps do?

 

[AdamWill]

No-one was really confused, I just wasn't clear. I said they cost me $110, someone said 'that's the same as retail!' and I clarified that I'd actually meant $110 Canadian.

BTW, how does 'clear' become a drawback? Could you maybe pick another adjective?

To me clear must be a good thing...

 

[Necros]

It sounds better, but different to the iriver...better because it sounds cleaner, but also different in a very slight way because it sounds maybe brighter or thinner too.. Bass is cleaner which I like, and can tell slight muddiness has gone. Normal EQ.

Probably just trying to spot the differences...placebo

trying to "listen" too hard and spot differences and I really need another "warmer sounding" portable headphone amp and switch over the two.

Encodes are VBR OGG @ 160kps-180kps.

Defo worth the asking price.

 

[Natsuiro]

Adamwill: I'm not sure how adverse it would be for sound quality, but you can get an ac adapter for really cheap at radioshack that will fit your 9v battery snap. http://www.radioshack.ca/estore/Prod...roduct=2731552

Necros: All the op-amps have a different sound sig, so switching them would change the sound.

 

[nikongod]

any computer you will build will ahev ample power on the 12V chanel.... just put a plug somewhere to run your amp off of the computers regulated 12V psu...

 

[AdamWill]

nikongod: neat idea, but then I have to trust myself not to mess up the wiring and to create some kinda adapter to wire it to the terminals in the amp. I like natsuiro's suggestion best, think I'll try one of those out - thanks!