[budget minded]

The 24V battey system will sound about 40% better than the AC power supply, probably 15 % better than a 12V.
 
A close fiend, Rex has one also, and he did a Cardas speaker binding post mod that improved the sound by another 30%.

Other mods we have done is to use the AMR fuse that sells for $20. That makes about a 3-5% improvement depending on your system.

And another 10% improvement came with using the drum gel pads underneath the amp. out of the house, just slip this in your reference system. Then you will have to buy a second one.

85% improvement?! WOW! i might think you were exaggerating a bit if you said 110%

here is the best deal on 2-12V batteries for $15.92.

that is a pretty good deal! was imagining getting a couple cheap car batteries or some lithium ions, but neither option would be that cheap. it's nice when a significant mod is reasonably priced. i already have a 12v smart charger too i could put to use.

i just joined this forum to see some more reviews other than the TNT shootout where it outdid "giant killing" dayens ampino & trends amps and the positive feedback full review. i'm looking for something a little more liquid sounding than my panasonic class D receiver and as trends supposedly sounds better than that in a big shootout at stereomojo, and the TBI spanks that, it sounds like a $500 no brainer upgrade instead of a gainclone or KingRex.

it's a shame this amp doesn't have more word of mouth if it truly is as musical AND detailed as described.

[Rclark]

85% improvement?! WOW!

ROFL 

[fredgarvin]

Something that should be noted about the TBI is that it is still in production and maintaining comfortable pricing. We've all seen other small amps, class T etc, enter the market, attract a following and interest and then go out of production very quickly. Some others have stayed in production but upped the pricing considerably, even with different parts.  The easy modding path is another plus.

[wisnon]

The TBI, like IFI Audio products, Nuforce DDA-100, Dspeaker AM 2.0 and Vinatoo speakers are true "hero" products that help to spread the hobby beyond an elite circle.

Kudos to them.

[rodge827]

The TBI, like IFI Audio products, Nuforce DDA-100, Dspeaker AM 2.0 and Vinatoo speakers are true "hero" products that help to spread the hobby beyond an elite circle.

Kudos to them.

+1

I'm dumbfounded at how good some of these pieces that have brought the fun back into this hobby, and at very reasonable prices!

[srclose]

Just finished a generous amount of time with the TBI.  Since the Super V requires a sub ouput, it was necessary to leave the tube buffer in front of the TBI, with buffer outputs to the sub amps and to the TBI.  This required having the tube buffer volume at about 9 and the TBI volume at about 3.  Swapping in the TBI for a Clayton Audio S40 50W per channel class A SS amp.  All three power sources were used, and the TBI AC supply, 24v battery, and internal AA battery supplies all provided way more than adequate power.  You could blow the doors off with AA Energizers.  Power was not a problem.  Super V rated at 97dB sensitivity.
The AC power supply was eliminated pretty quickly.  This provided a more flat, mechanical sound than the battery power.  I was not as interested in using the AA internal batteries, so I checked them out primarily to be sure that they provided sufficient power.  All of the serious listening was based on the 24v battery. 

The TBI was quick, articulate, and clean.  There was no sense that lower or upper registers were neglected.  No muddiness or congestion.  No sizzle for high frequencies.  This was a good, pleasing sound.  Plenty of punch and drive.  In the end, though, the TBI was not as pleasing as the Clayton.  Images had more body, solidity particularly for lower frequencies with the class A amp.  Soundstage width was somewhat restricted with the TBI.  A rounder, three dimensional, organic sound was had with the Clayton.  Then, the Clayton is 9 times more expensive than the stock TBI.  I'm not sure of all the upgrades, but this unit must have had upgraded speaker posts and used the AMR audiophile fuse. 

Thanks for the opportunity to audition the TBI to Ozark Tom.  Things are changing and the potential for obtaining first rate sound for a fraction of the energy associated with other amp topologies is of real significance.
 
Stephen

[OzarkTom]

Thank you Stephen for joining the tour. We appreciate your feedback. Stephen is sending the amp back to Rex for replacement of the AMR fuse. Are their any other candidates that want to hear the amp?

It would be interesting to hear the TBI with the IFI IDAC on a pair of Tectonic M-Lores. That would have to be a best buy system that anyone would love to own for the money. That system would fall around $1500.

[wisnon]

The inclusion of the iUSB Power for $200 more would not break the bank and step up performance a notch.

[Rclark]

I agree with your speculation Tom, for that money it would have to be a killer pairing.

[WC]

Thank you Stephen for joining the tour. We appreciate your feedback. Stephen is sending the amp back to Rex for replacement of the AMR fuse. Are their any other candidates that want to hear the amp?

It would be interesting to hear the TBI with the IFI IDAC on a pair of Tectonic M-Lores. That would have to be a best buy system that anyone would love to own for the money. That system would fall around $1500.

Those are all components that I am looking at. Seems like they would work pretty well together.

[beanstocks]

Hey Tom;  Would like to be included in this tour.  I messaged you but my email address is faulty.  New email submitted but...??  Ron Nishimura.  808 732 1949  ronnishim@gmail.com.  Have a pair of Tannoy monitors and Altec A-7 with modded Heath W6ms and Yamamoto A-08S 2 watter for comps.  Also a pair of ESL 5 7s with new bass panels just received back.  Let me know please.

[budget minded]

it's looking like i'll upgrade amplification to an MG3 from my panasonic receiver before a $700 DAC as another person that had one and similar to mine paradigm monitors with aluminum domes thought the SA-XR55 is a little too clinical sounding. that, and the amp is about $200 cheaper. it will let me better hear the DACs i already have, and i do like the detail and extension of my panasonic DAC if not the synergy with it's amps. it might sound a lot better with smoother amplification.

it's nice that someone's making a "high end" amp for just $500, especially when it's not only much more efficient than class A & A/B amps, but also much cheaper to operate than tube amps, and cooler in the summer too. i find it reassuring actually when tube amp owners say "it isn't quite as big sounding and more detailed" as i can't picture liking too much of a warm and forgiving tube sound. tighter bass in particular suits my tastes better right away. it sounds like a perfect balance between detail and musicality.

[Folsom]

Bypass the crappy volume Pot on it, if you want to see what it really has got.

Perhaps it has some low quality signaling coupling capacitors to replace as well.

You can make ok amps sound decent by doing that, or make great amps sound excellent.

[wisnon]

DoS,

This is class D an you have to be careful about changing components. Jan has chosen the parts and arranged that layout on purpose. It is possible that you increase cross-pollution of EMI/RFI noise by changing components ad-hoc as you say.

I cant speak much about the volume pot except to say that bypassing does not seem necessary, because when run full-on it is 99% out of the loop and then the better pre-amp can control the volume level. That seems a cheaper and simpler solution.

[Folsom]

Perhaps the volume pot at full volume is close, but I don't much care for the sound of anything through plastic pots.

The input parts you replace with the same values. In general it is hard to go wrong when you are expecting lower ESR, etc. You'll probably reduce noise. I can assure you that at $500 you won't see Teflon capacitors or anything like that, at the input. If anything I'd be more worried about needing to replace the Pot with a resistor value to keep the amplifier functioning properly because even at full volume on the pot, there is a resistive value since it is in parallel.

[wisnon]

OK,

Thanks for the detailed response.

[rodge827]

DOS,

I spoke to Jan about removing/bypassing the volume pot and he said it wasn't a good idea.
I also asked him if a straight power amp was in the mix, with the same topology as the MG3 and he said no.
Perhaps if there is enough interest in a straight amp he may consider it?

Why not purchase one and figure out how to do the bypass.
I would be very interested in finding out if it sounds better.
I would do it, but I don't have the know how.

Chris

 

[budget minded]

Are their any other candidates that want to hear the amp?

how much is shipping on the amp? as i'm already interested in buying one, it would be nice to hear it in my system before buying a unit, but not if would be something like a $50 rental. it's shipping with batteries isn't it?

speaking of that, i've only seen talk about using 1.5v AA batteries in the unit, but isn't there a 3v lithium ion batter that's the same size as AAs that would turn the unit into a 24v internally powered amp?

it's a shame about the amp not being offered in any other configuration. a larger version that included a better step attenuator volume control and input switching would be nice. if only my TV's tosilink out worked, i could use the DAC i'm getting for switching purposes.

i thought the tour was already over and have only just read up to this page. i'm interested in trying before buying for sure.

[Folsom]

DOS,

I spoke to Jan about removing/bypassing the volume pot and he said it wasn't a good idea.
I also asked him if a straight power amp was in the mix, with the same topology as the MG3 and he said no.
Perhaps if there is enough interest in a straight amp he may consider it?

Why not purchase one and figure out how to do the bypass.
I would be very interested in finding out if it sounds better.
I would do it, but I don't have the know how.

Chris

Maybe it has digital volume? That is a very different story.

Either way I doubt it is a question of whether or not bypassing would be good, and more a question of what it would take. For example maybe the amplifier is dependent on the distinct values of the pot. You'd have to measure and replace with high quality resistors (2 or 4 depending on how it is setup). There is always a chance that things are inaccessible, too. if you had to cut PCB tracings they may not be on the surface, etc.

I guess I need to see the inside to have a real good idea. Yes I looked around google images, no luck. Buy one? I just purchased parts to build an amplifier so that isn't going to happen right now.

[Freo-1]

how much is shipping on the amp? as i'm already interested in buying one, it would be nice to hear it in my system before buying a unit, but not if would be something like a $50 rental. it's shipping with batteries isn't it?

speaking of that, i've only seen talk about using 1.5v AA batteries in the unit, but isn't there a 3v lithium ion batter that's the same size as AAs that would turn the unit into a 24v internally powered amp?

it's a shame about the amp not being offered in any other configuration. a larger version that included a better step attenuator volume control and input switching would be nice. if only my TV's tosilink out worked, i could use the DAC i'm getting for switching purposes.

i thought the tour was already over and have only just read up to this page. i'm interested in trying before buying for sure.

The battery compartment is fused to a 125V 2A fast blow fuse, so if you stick 3V batteries, it will pop the fuse.  The only way to run the amp on the 24V line (battery or AC) is via the jack input.  The nice thing about this amp is it is near bullet proof, as the fuses go before any damage occurs, thus ensuring long lasting safe performance.  The 24V line is fused with a 125V 4A fuse.

As far as being green, it sure is, as it idles at only one or two watts.
 
The TBI amp sounds excellent at it's price point.  There are many fine aspects regarding performance.  My one issue with it is playing classical with the 24 V supply.  The sound with massed strings was not to my liking.  It is better with 12 V for classical, but then one needs the right speakers to get the proper sound.

In my case, I solved that by getting a pair of tube mono blocks (DIY) that output 55 WPC (definitely not low wattage).  Contrary to what many think, a properly designed tube amp is not "rolled off" or has flabby bass.  Because it was a DIY, was able to put in very expensive parts and still keep the cost down.  Since it uses 1625 tubes, they are cheap, long lasting, and reliable.  It provides that unique harmonic tonality that only tubes can (subjectively) provide, and still give that clean detailed sound generally associated with the best solid state (including the TBI).

http://www.audiocircle.com/index.php?topic=113695.0
 
As they say, it's "Horses for Courses"