[AmpDesigner333]

Just checking if anyone out there's interested in running Maraschinos from batteries....

Since Cherry Maraschino amps have an external power supplies, this seems like a natural option.  We discussed this back in 2012 (pre-Maraschino), but now we're revisiting the idea after much refinement of our designs and expansion of the product line.

In the case of a battery powered amp, might as well leave the option of powering a DAC DAC with the same batter supply, too!

Perhaps this could be a box with a pass-through, so you can switch between AC and battery power (while charging).  Any feedback on this idea would be greatly appreciated.  Basically, we'd like to know if there's enough interest.  Maybe a Kickstarter project is in order 

[Danny Richie]

Here is the system that we took to the last show. https://parttimeaudiophile.com/2019/06/04/gr-research-dodd-audio-lone-star-audio-fest-2019/

It was all off the grid except for the amps powering the servo subs. Everything runs on 12 volts. I have have some Dodd Audio, 30 watt mono-block tube amps that run on 12 volts.

I love the sound I am getting from the little chip amps. I just wish I had that sound but more power.

So I'd really be interested in trying whatever you might come up with.

[Freo-1]

I don't think it's a good idea.  Read the following link to better understand why there are issues with this approach:


[size=78%]http://lightharmonic.com/blog/2015/07/24/power-supplies-and-noise/[/size]


 

[Danny Richie]

I don't think it's a good idea.  Read the following link to better understand why there are issues with this approach:


[size=78%]http://lightharmonic.com/blog/2015/07/24/power-supplies-and-noise/[/size]

Actually some of that is a bit misleading. The performance of batteries varies a lot with type, brand, and size. And I (and a group of inner circle friends) have tried a ton of them. So we've learned how to get the most out of them and in most cases the pros really outweigh the cons and the overall performance is not only very high but at a much lower cost than standard power supplies. The batteries are also consistent regardless of where you take them. A/C noise varies all over the place depending on where you go. 

[Jonathon Janusz]

Tommy,

If maraschino can run from a 12V source voltage right now, Dave at P.I. Audio already makes this:

https://www.audiocircle.com/index.php?topic=111257.0

which sounds kind of like what you were talking about in a "battery power supply" for maraschino?

Come to think of it, considering there are 36V and 48V supplies right now for maraschino, couldn't one just string a series of three or four 12V batteries together to get the called for source voltage, or am I mistaken thinking maraschino's replaceable power supplies are right now DC supplies and they are actually feeding AC in to maraschino with the DC conversion happening inside the amp?  Based on what I thought I remembered reading in the other thread, you were discussing a need for a DC-DC conversion, so I don't think this is the case?

It reads to me like you're already there, maybe just not as elegant as going from wall -> ctek charger -> one 12V battery -> maraschino?

[AmpDesigner333]

Actually some of that is a bit misleading. The performance of batteries varies a lot with type, brand, and size. And I (and a group of inner circle friends) have tried a ton of them. So we've learned how to get the most out of them and in most cases the pros really outweigh the cons and the overall performance is not only very high but at a much lower cost than standard power supplies. The batteries are also consistent regardless of where you take them. A/C noise varies all over the place depending on where you go.

I agree!  It’s VERY misleading.  Show me some scope shots and I might pay attention, but I’ve measured “battery noise” in the past because I designed many portable audio devices, and with a simple cap across the battery, which is typical anyway, and doesn’t need to be very large, there is no noise.  Also, batteries are typically powering DC/DC converters, and noise on the input is filtered or regulated out.  Even the most beginner engineer knows these things, so I’m guessing the author isn’t one.  Power supply design isn’t rocket science.

[AmpDesigner333]

Tommy,

If maraschino can run from a 12V source voltage right now, Dave at P.I. Audio already makes this:

https://www.audiocircle.com/index.php?topic=111257.0

which sounds kind of like what you were talking about in a "battery power supply" for maraschino?

Come to think of it, considering there are 36V and 48V supplies right now for maraschino, couldn't one just string a series of three or four 12V batteries together to get the called for source voltage, or am I mistaken thinking maraschino's replaceable power supplies are right now DC supplies and they are actually feeding AC in to maraschino with the DC conversion happening inside the amp?  Based on what I thought I remembered reading in the other thread, you were discussing a need for a DC-DC conversion, so I don't think this is the case?

It reads to me like you're already there, maybe just not as elegant as going from wall -> ctek charger -> one 12V battery -> maraschino?

With some modifications, Maraschino monoblock boards can run from 12VDC.  However, voltage drop from a BATTERY, with no regulation, over time will affect performance, and the power output will be quite low (gets lower as the batter discharges).  A DC/DC assures no droop and allows a boost function, converting low voltage, high current to high voltage, low current. The rail caps hold rail voltage through peaks of higher current draw and even out the “load”.  Handling the dynamics of music is another part of this puzzle.

[Jonathon Janusz]

With some modifications, Maraschino monoblock boards can run from 12VDC.  However, voltage drop from a BATTERY, with no regulation, over time will affect performance, and the power output will be quite low (gets lower as the batter discharges).

This is something I've heard with Danny's battery gear, and at least as far as I know has to this point simply been managed by keeping an eye on the output voltage of the battery and simply making sure the battery supply doesn't drop too far in to the not good zone while doing critical listening.  I think this is part of why the bigger-is-better recommendations for batteries is out there; a single big battery can stay good to go longer than a small battery (or even a bank of small batteries hooked together).  The question of whether one needs to go the extra lengths to try to squeeze even more love from a battery with additional parts I think comes down to the length of time one needs the battery to be in top form for a single listening session (because the battery can be recharged when the system is idle) and maybe the wear and tear on the battery as far as charging cycles/management (which I guess is an advantage - in audiophile terms of cost - to batteries because they are "cheap" enough to not be too worried about replacing).

A DC/DC assures no droop and allows a boost function, converting low voltage, high current to high voltage, low current. The rail caps hold rail voltage through peaks of higher current draw and even out the “load”.  Handling the dynamics of music is another part of this puzzle.

So, with some mods, could one get a maraschino to run for say a few hours on a single big topped off battery?  Without mods, could one put a bank of batteries together to get the needed voltage to get a couple hours of top-quality play time out of maraschino, keeping in mind limitations of voltage drop?  If so, in someone like Danny's case - a person already invested in a pile of battery gear and batteries readily on hand - being able to try this out, comparing maraschino on batteries versus AC supply as a proof of concept from a subjective sound quality perspecive, would be possible without (or to see if it would be worthwhile) to go to the effort and expense to kickstart a more robust battery solution?  Is maraschino circuit as-is sturdy enough to handle at least a little voltage drop over time from the power supply without causing big problems (as in breaking something) so that customers or folks who could get their hands on an amp to try out could check out batteries right now, even if a listening session was short, for themselves?  It might also subjectively add data points to the influence - or not - of aftermarket power cords, power conditioning, etc. on maraschino on AC power as-is by having a quick way to just get the whole AC system out of the equation to see if there is a difference in sound?

[rollo]

  Leave it be IMO. Danny was showing a complete system. Maybe it was just synergy. I own two Dodd battery powered devices BTW.  My experience is lack of dynamics and weight as opposed to AC powered. Ac when filtered properly is still King IMHO.
  However moot. Only way to really know is to build one and compare to original and stop guessing.


charles

[Danny Richie]

The system that I just showed (LSAF) had three 100 amp hour batteries. And there was a battery buffer on the Mac-mini that is external and a internally battery buffer on our DAC. I keep the C-Tek chargers on our batteries 24/7. Even running them all day long at the show the batteries voltages never drop below 13 volts. Most of the time they stay in the 13.4 volts and up range. So they never run down. And surprisingly the chargers put no noticeable noise on the line.

And one of the things I hear the most at the shows is the surprise at how low our noise floor is. We hear it over and over.

[Danny Richie]

  Leave it be IMO. Danny was showing a complete system. Maybe it was just synergy. I own two Dodd battery powered devices BTW.  My experience is lack of dynamics and weight as opposed to AC powered.

It depends on the size of the batteries. I get no drop off in dynamics or weight using the big 100 amp hour batteries.

[Jonathon Janusz]

Only way to really know is to build one and compare to original and stop guessing.

I'm sorry if you misinterpreted this entire thread, but that is exactly what we are discussing here.  No one is guessing anything.  Tommy's initial post was asking if there is any interest, Danny's has been discussing his experiences with battery power in the past and with that as a reference point how his current setup mitigates some of the challenges Tommy brought up, and mine have been asking about details in the maraschino design to determine if it would be possible to try it out as-is or if there absolutely needs to be some modification work done to even try it out to bring the time/cost down of giving it a shot to see the results.

I know that a lot of similar threads on AC get spun out with folks projecting what they've never heard on what they already know to make speculative conclusions, but that really isn't the case here.

Thank you, though, for sharing your experiences with battery power regarding Dodd gear, your vote to leave well enough alone with the Maraschino amps, and your own speculation on whether the approach is worth trying at all or not.

[AmpDesigner333]

Prediction: There will be no difference in the sound aside from high power peaks.  This is because the Maraschino runs from a floating ground locked to the source, plus power supply rejection ratio is huge even at high frequencies.  In effect, due to the floating supply, the current AC powered Maraschino amp runs much like a battery powered one would. We understand interests change and some ideas get bursts of attention, but we need pretty compelling reasons to undergo any project like this.

[Danny Richie]

A little off topic, but I'd be glad to try another set of amps out, and compare them with amps that I have here.

I can compare power cables, Uber Buss, balanced power supplies, etc and let you know if I hear any differences.

And I can either make the feedback public or private. Your choice. If I like them then a public recommendation is not a problem.

But I would request an amp with single ended inputs this time.

[sumoking]

My guess is that the amp will sound better with batteries.
Would love to hear the cherries as the amp for this experiment.
The cherries are really quiet as is. Can batteries improve it further still?
I think they will improve it.

[Wind Chaser]

I love the sound I am getting from the little chip amps. I just wish I had that sound but more power.

That's how I felt about the TPA 3116. The Maraschino's provided the power I craved with extraordinary musical transparency from top to bottom.

But I would request an amp with single ended inputs this time.

None of Tommy's amps have single ended inputs, but he does supply an adapter. 

[AmpDesigner333]

None of Tommy's amps have single ended inputs, but he does supply an adapter. 

We can also customize and put RCAs where the XLRs usually go! This kills the ability to upgrade to balanced in the future, but it skips over the adapter (shorter signal path).  That also saves space in some cases.

[Danny Richie]

We can also customize and put RCAs where the XLRs usually go! This kills the ability to upgrade to balanced in the future, but it skips over the adapter (shorter signal path).  That also saves space in some cases.

Great. I have a selection of really nice RCA cables, but it is hard to find really good XLR cables.

[AmpDesigner333]

Great. I have a selection of really nice RCA cables, but it is hard to find really good XLR cables.

These test as well as the ones Audio Precision includes with their $30,000 analyzers:
Audio 2000s E02101P2 XLR Male to Female 1 Feet Microphone Cable (2 Pack) https://www.amazon.com/dp/B00O5UBK5U/ref=cm_sw_r_cp_api_i_0y7eDbEDBBKCE

$11/pr !!

[Danny Richie]

These test as well as the ones Audio Precision includes with their $30,000 analyzers:
Audio 2000s E02101P2 XLR Male to Female 1 Feet Microphone Cable (2 Pack) https://www.amazon.com/dp/B00O5UBK5U/ref=cm_sw_r_cp_api_i_0y7eDbEDBBKCE

$11/pr !!

I use a different kind of test. It's called a listening test, and it separates the good form the bad real easily.