Portable DAC compatible w/ iPhone or iPod

Hello, I'm a spinning enthusiast who loves to jam to some motivational music at my local LA Fitness spin classes. The instructors do the best they can outputting their playlists from the phone mini-jack split into a stereo RCA interconnect that connects into the gym's reasonably powerful amp & speakers.
Often the sound quality is just awful. No punch to the Metallica or Michael Jackson or whatever music they choose.
It would sound so much more forceful but less fatiguing at the same time if the instructor's phone or iPod could be docked in a way that the data will upload raw to the portable DAC.
I've been looking for a versatile DAC that can be easy to use & hookup to their system quickly. I've seen the one company in California that makes triangular portable DAC's, but I don't recall their name right now. Basically I'm looking to mount up my phone & still get good sound
Elevick - I appreciate your expertise as a spin instructor. I'm thinking that having an actual small high quality DAC in the spin class that the instructor can plug his phone into is going to produce noticeably superior sound even with low quality MP3 music tracks. I'm sorry that you "gave up" on trying to get decent sound. What source were you using? Did you just connect up to the mini-jack? Did you try it with a DAC?
What I hear in these spin classes is classic low quality iPod through mini jack crappy. I believe this is very fixable!
I spoke with my favorite instructor about it this morning & she is willing to try the Nuforce when I get it. I let her know I'll need a place to plug up the wall wart & I need some exposed RCA interconnects. Both of these requirements are potential issues since the back of the equipment rack is padlocked & only the manager is authorized to unlock it. Also, all the outlets appear to be in use so I would need to haul in my own multi outlet strip. I plan to ask the front desk if we can run a set of RCA interconnects through one of the unused auxiliary inputs (if there are any left) from the back & long enough to dangle out front
I'm thinking of that other company that makes clever little "Toblerone candy" shaped mini DAC's
I think you're referring to this company: http://www.highresolutiontechnologies.com. Their Music Streamers used to be triangular. It looks like they've changed the case. I have no experience with any of their products, but they get good comments from owners and reviewers.
Thanks Mingles - HRT is the name of the company I'm thinking of. I'll check their website for current models and features.

The Nuforce Icon iDo seems to be the right product for what I'm needing it to do. The only thing better would be a battery powered version.
I've taught in about 10 different studios. The best system was one that I installed for them (just Audiosource gear with all weather infinity's and a sub). The one studio in Gold's had an ipod dock that never seemed to work. There's only so much you can get out of a commercial Bose system that is strictly about loud midrange sound with overemphasized bass. I've even tried using a laptop to no avail. Also, you should do more homework. Just take in a recording that is noticeably in stereo (Beatles?). The commercial systems in Golds and LA tend to be wired in mono even if they have 2/4 speakers. Makes a ton of sense since the people are sitting all over the room and it sounds awful if you only hear 1/2 of the track...

You may get lucky and a manager will let you leave a pair of rca's hanging out the back of the system for when you have class and hope that no one steals them. We seem to lose cables weekly. For a power strip, take in a $10 Belkin.

Even if things sound a little better, you are at the mercy of the studio if you leave the unit there. Things can't get much better since most spin studios are big boxes made of either drywall or concrete block or glass and resonate like mad. Finally, what may sound crappy with 6 people in class might sound way better with 25 people in the room to act as diffusers. Now you need to take a bunch of friends with you.