The TEAC is on it's way it's next to AudioJerry in WI.
I got a good 250 hours on it (if not a little more)
It is a remarkably silent running amp...the in-between 'blackness' in songs was spooky different and excellent. It made my hairs (where they still are 
) stand up on end at times.
Sure, it will power Maggies without thermal shutdown....but was weak-kneed powering it. It was far better overall and made a nicer portrayal of things than the 150watt AudioSource Amp3 did a year ago. So ...
Hi Chair Guy (John),
First, thanks again to Chris for lending you the RWA Teac, and thank you for all the time you put into breaking it in, listening, and posting your findings.
You certainly picked up on a lot of the improvements over the stock unit, and the benefits of converting this unit to SLA power. Let me answer your questions:
Vinnie, would some of the 'snap' I felt was missing here be ameliorated by a change to a different output inductor (as was mentioned a few weeks ago)? Or, powered by a larger capacity SLA battery with more energy reserves?
Regarding changing the output inductors, I don't believe that this would give you more bass output (perhaps it would change the presentation of the midrange and top end, "snap factor", etc). I did order a pile of those new inductors for the new board that I am working on
Regarding using larger capacity batteries, this will not give you more power because this is not an energy reserve issue (during experimentation, I've tried that Clari-T and Teac on some BIG SLAs that are used for motorcycles). It is most likey an issue of your speakers simply needing more power than the 30 watts to obtain the level of bass response/slam factor that you are looking for. The batteries used in the Teac can easily provide more current than the Tripath chips can ever use at max power. The voltage doesn't sag under full power and these SLA batteries can provide BIG current when needed. Moving to larger cells will allow for longer play time between charges (ex. going from 3.4Ah batteries to 5Ah batteries), but you will not get any more power out of the Tripath chip in doing this.
Alternatively, is it possible to power the 100watt Tripath chip (like Bel Canto's) with battery power? Will it require something more akin to a car battery with far more capacity and 'cranking' amps to drive it?
Technically, any amp could be powered by battery, but as the amplifier wattage becomes larger, the voltage rail(s) tend to be larger. The higher the voltage, the more batteries you'll need, and it becomes impractical. For example, stacking six large 12V SLAs to obtain a 72V rail will be cumbersome (BIG ol' heavy battery enclosure), as will charging them.
Now, you may ask why do car audio amps run off of a 12V system and can output 100 or 500 or 1000 watts? The answer is that they use DC-DC switching converters to convert the 12V to a higher voltage. Sure, this can be done for a higher power Tripath amp, but the switching conversion generally adds switching noise (think stock Teac) and IMO defeats the purpose of battery purity/simplicity that makes it sound sooo pure and clean. In this case, you might as well go with an AC linear power supply, which is what everyone does.
I really thought the RWA TEAC had some great attributes...and not to be overlooked is Vinnie's hard work, honesty, innovation and straight-shooting that's been a boon to Audio Circle since he arrived.
John, I want to thank you again for all your time and effort, and I totally understand that this just wasn't the best suited amp for your system and tastes. It is ALL about synergy, listening peferences, etc.
I've had a few RWA modded Teac customers tell me that it has more bass slam than their 100 watt amp. I've received feedback from someone who thought it was a tad too bass heavy, and now I just read your post that states you were looking for more bass. I believe all of you, and there is no wrong opinion. Yours was very honest and I really appreciate it, as I'm sure everyone who has read your post does.
Again, it is ALL about synergy, listening peferences, etc. This happens with all amplifiers. For another example, I have a Clari-T customer who is using 86dB speakers (I forgot the model) and LOVES the combo. He is also not into playing loud and he says the Clari-T has superb low-level detail with his speakers and never wants to go back to his 75-watt amp (I am not going to mention any names because it is not important). For many others, the 6-watts of the Clari-T powering 86dB speakers would leave them craving much more...
Thanks to all for reading this thread and posting your feedback. It is all very valuable and we're all learning here.
