[rodge827]

That was quick 

[zilch0md]

Hey Chris,

Mike,
Thanks for answering my question.
I see you have put a lot of thought into using LiPo packs and sharing your experience is most appreciated. 
There are many on this thread who may take you up on your suggestions.

Would this battery unit be OK or is the amp level, 3a @ 19v, to low?

http://www.amazon.com/Anker-Ultra-High-Multi-Voltage-Notebooks-Compatible/dp/B00B45EOYS/ref=pd_sim_e_1

or this one?

http://www.amazon.com/Capacity-33600mAh-Portable-External-Notebooks/dp/B0063KXZQ2/ref=pd_sim_sbs_pc_3

Chris

I was just letting this thread know about the product at the first link you've provided - coincidentally.

That second one is a beast!   Check out the dimensions: 8.4 x 0.8 x 5.1 inches     And it weighs 1.8 pounds!

I think that one is overkill for the MG3, unless you want to go camping for a month without access to AC power.  But as a desktop power supply, the size and weight wouldn't be as great an issue and it would offer a longer play time between having to recharge it.

I'm confident that the 3A rating on these is sufficient for the MG3, especially since the MG3 can't pull as many amps on 19V power as it can on 24V power.   If you're running efficient speakers (or headphones), the MG3 might never even peak to 3 amps.  Keep in mind that Jan Plummer says you have to feed the MG3 27.5V, pushing it hard, I presume, to blow the 4A fuse.   

If I were you and willing to experiment, given that no one else has actually heard it with the MG3, to my knowledge, I'd get the Anker Astro Pro 2. 

Regarding potential play times, I've logged 6 hours on a fully charged 3600 mAh 6-cell (25.2V) LiPo pack and the voltage has fallen to 3.84V per cell (23.0V total). 

Look at this chart and tell me how much time I have before the voltage falls from 3.84V per cell to 3.4V per cell, where my alarm will sound:



Yeah!  In six hours of use, I've only consumed about 0.2 of 8.2 total units of time available with a 3600 mAh battery!!!

0.2 is only 2.44% of the total capacity (and that's sticking to my plan of discharging no further than 3.4V per cell).

This could end up being off by quite a bit, but going by the chart and the voltage I'm measuring after only 6 hours of use, I'm predicting the 3600 mAh LiPo pack will give me 246 hours of play on a single charge! 

If that seems impossible, consider that Jan Plummer has told me it's not unusual for people to go "weeks" on a single set of 2200 mAh AAs inside the MG3's battery compartment!

Assuming the specs aren't inflated (and my attempts at forecasting results with my 3600 mAh pack are reasonable), a 20,000 mAh battery pack (i.e. Anker Astro Pro 2) would be good for 1367 hours of play at the levels I'm running the MG3 > SM45.   Sheesh!  Even if that chart is off by a factor of two, we're good for 683 hours of play with a 20,000 mAh pack.   If it's off by a factor of ten, we're still good for 13.7 hours of play - enough for a long day of listening before putting it back on the charger overnight, but I suspect my forecast is "in the ball park."

Really, a 10,000 mAh Anker Astro3 is more than enough capacity, but it only puts out 12V max.  The Energizer XP8000 has plenty of capacity, too, at 8000 mAh, but it's limited to 2A loads at 19V - which sounds fine with my MG3 running no higher than 8 o'clock on the volume control, but I don't like the idea of having a 2A ceiling.

That leaves us with the Anker Astro Pro 2 (at your second link, above), as having too much capacity perhaps, but a 3A output.

 

Mike

[zilch0md]

We're out of sync, Chris - leap frogging each other.   

[rodge827]

We're out of sync, Chris - leap frogging each other.   

 

Thanks again for all of the great info.

I will need a pair of these amps for my system, run as mono blocks.
A single MG3 with 24v 32w output works OK, but 2 MG3's will run cooler with better headroom as mono blocks with a shorted output (24v with 40w output).
These battery power supplies look to be the answer to keeping the cost to performance ratio in line.

Chris

[zilch0md]

I recall reading earlier in this thread about using one channel on each of two amps and that Jan had predicted a 30% increase in Wpc, but I'm clueless as to why the unused channels have to be shorted. 

?

[rodge827]

I recall reading earlier in this thread about using one channel on each of two amps and that Jan had predicted a 30% increase in Wpc, but I'm clueless as to why the unused channels have to be shorted. 

?

There was a mention and discussion about shorting the unused input over in the TBI Amp Tour 2 thread.

http://www.audiocircle.com/index.php?topic=115309.80

This was posted by Ozarktom on page 5:

"The TBI puts out 20 percent more with the amps as mono. Just use one channel of the amp and short out the other channel. The shorting does make an improvement in sound.  This would give about 40WPC on 24v AC or battery and that should be very loud with the Super V's."

Couldn't hurt?

[zilch0md]

Ok, it must be the right thing to do. 

[zilch0md]

Resurrecting this post after two months of silence...

Here are some photos of my "transportable" rig that allows me to travel with the MG3 and a pair of Audeze LCD-2 orthoplanar headphones.

First, this shows the rig set up on a table, but with heavier gauge speaker wire (10AWG, 462-strand OFC) that I had to downsize for use in my travel case:



And here's the rig in its case:



44.1/16 and 96/24 WAVs on multiple 64GB MicroSD > Sony PCM-M10 Line Out > 24VDC-powered TBI Audio Millenia MG3 (~5.1 Watts into 50-Ohm) > TBI Impedance Match > Audeze LCD-2 rev.1



1)  Open the case
2)  Connect headphone cable to the LCD-2's mini-XLRs
3)  Connect the 24VDC LiPo battery and attach alarm/monitor
4)  Connect interconnect cable to Sony PCM-M10
5)  Turn on the TBI Audio Millenia MG3 and listen to music! 



Jan Plummer (of TBI Audio), built the impedance match to reduce the hiss caused by excess gain when plugging the Audeze LCD-2 directly into the amp's binding posts.  Audeze technical support says the LCD-2 can handle output from amps rated as high as 81 Watts rms per channel into 8-Ohms, but I was hearing a low level hiss prior to getting the impedance match.  Now - it's perfect - and the sound is amazing!

Here's a schematic Jan provided showing one channel of the resistor network ("A" means Amp, "H" means Headphone):



I believe this idea of using the MG3 with headphones, via an impedance match, was pioneered by a member of Head-Fi.org who goes by the handle "SMG52."

Mike

[rodge827]

Very nice...been following the thread over on Head-fi. 

How many cards can the M10 handle at the same time?

[Freo-1]

Very nice...been following the thread over on Head-fi. 

+1   Good thinking.  That is excellent use of the amp.  I bet it sounds great!

[OzarkTom]

Jan heard the modded Cardas post version of Rex and mine and now is offering this on his website for $650. Jan was impressed.

[zilch0md]

Very nice...been following the thread over on Head-fi. 

How many cards can the M10 handle at the same time?

Hi,

The PCM-M10 can only hold one microSD card at at a time (64 GB SDXC cards, reformatted to FAT32 for compatibility with the PCM-M10).

I just meant that I carry multiple cards (six, currently) to hold my modest, but growing library of WAV files.

Mike

[zilch0md]

Jan heard the modded Cardas post version of Rex and mine and now is offering this on his website for $650. Jan was impressed.

Hey,

I thought about that upgrade for a while, but settled on the standard posts. 

Now, I'm afraid to listen to an MG3 with Cardas posts!   

Mike

[zilch0md]

+1   Good thinking.  That is excellent use of the amp.  I bet it sounds great!

Thanks!

The Audeze LCD-2 and LCD-3 both scale nicely with more power.  They're known for sounding pretty good even with most portable headphone amps, outputting only 100- to 500-mW into 50-Ohms, but Audeze recommends a minimum of 1000 mW into 50 Ohms, up to a maximum of 13 Watts rms per channel. 

They're efficient enough to achieve more than reasonable SPL with only 100 mW, but the bass control and dynamics improve greatly as you get up to 1 Watt and beyond. 

With the 5-Watt into 50-Ohm output of the MG3, the dynamics are amazing (with recordings that offer good dynamics) and those analog, natural, and organic qualities of the MG3, along with its superb transparency, low noise, and rendering of micro details that I can hear with my speakers (90dB sensitivity Definitive Technology SM45 near-field monitors), are enjoyed with the Audeze LCD-2, as well.  But the LCD-2 are not quite as highly resolving as the SM45s. 

On 24V power (where the MG3's gain is at its highest), using an SPL meter, I measure 85 dB between the ear pads of the LCD-2 when playing a white noise file with the MG3 volume control set at 9:00 o'clock (using the 1.0Vrms Line Out of the Sony PCM-M10 in combination with the TBI impedance match at the MG3's outputs). 

So, I don't have a lot of fine-tuning ability between silence and 9 o'clock, but it's actually better than what I get when using the Definitive Technology SM45 speakers.  The speakers are more sensitive (without the impedance match) than my LCD-2 (with the impedance match).  I'm stuck down 8 o'clock or less on the volume control, when using the SM45s, but that's in part because my head is only about two feet from each speaker.

 

Mike

[OzarkTom]

I talked to my friend in Michigan recently, that is using two Millenia amps as dual monos. He recently purchased a pair of the 8K plasma tweeters from Vaughn Acoustics to run with his Vaughn Line Arrays. Kenny told me that if he had only 10K to spend on an amp, he would have to buy two of the Millenia amps and these plasma tweeters. Kenny says those tweeters are a game changer for him. That is high praise to be running TBI's on that 40K system.

Audio Beat rated the Vaughn/Wavelength system as the best at RMAF.

[sugbob21]

i am also using 2 Millenia amps as dual monos with a Decware preamp. Volume on the Millenias is open about 80 %  just a touch off max. I am still using the provided power supplies  with Omega super 6 monitors .  I am quite happy with the setup. Question is ...can i connect my Omega sub directly to the speaker inputs of the Millenia amps?      Also .. are any other new tweeks to recomend ?

[zilch0md]

I talked to my friend in Michigan recently, that is using two Millenia amps as dual monos. He recently purchased a pair of the 8K plasma tweeters from Vaughn Acoustics to run with his Vaughn Line Arrays. Kenny told me that if he had only 10K to spend on an amp, he would have to buy two of the Millenia amps and these plasma tweeters. Kenny says those tweeters are a game changer for him. That is high praise to be running TBI's on that 40K system.

Audio Beat rated the Vaughn/Wavelength system as the best at RMAF.

That is indeed high praise for this inexpensive "chip" amp!

[StevenZ]

Sorry to resurrect such an old thread, but I was just checking to see if you guys are still happy with your TBI Millenia amps.  I just purchased mine and it should be here in a few days.  I plan to use it on some single driver fullrange speakers I've got.  These particular drivers used (Mark Audio Alpair 10.3) are incredibly revealing of upstream changes and tweaks so I'm curious to see how the test goes.

I'll also be pitching the TBI against my reference tube preamp and Class D Audio SDS-120 which are currently holding down the main rig duties.  Should be interesting to see if the TBI can dethrone my current gear.  Will report back with findings when the TBI arrives.

Cheers,
StevenZ

[gregfisk]

Sorry to resurrect such an old thread, but I was just checking to see if you guys are still happy with your TBI Millenia amps.  I just purchased mine and it should be here in a few days.  I plan to use it on some single driver fullrange speakers I've got.  These particular drivers used (Mark Audio Alpair 10.3) are incredibly revealing of upstream changes and tweaks so I'm curious to see how the test goes.

I'll also be pitching the TBI against my reference tube preamp and Class D Audio SDS-120 which are currently holding down the main rig duties.  Should be interesting to see if the TBI can dethrone my current gear.  Will report back with findings when the TBI arrives.

Cheers,
StevenZ

I'm still using mine and have been very happy with them, I'll be getting a pair of GR Research Super V's shortly which is the main reason I purchased them. They have loads of detail and are very smooth on top. Definitely let us know what you think and I'll do the same once I get my Super V's in house.

[StevenZ]

Thanks for the reply. Is the general consensus to use this as a standalone integrated or used as a power amp and external preamp?