[jtwrace]

Well said. As you probably know, Vinnie Rossi has a ton of real experience in the battery powered audio marketplace, likely with more production battery powered units sold than anyone out there. After a long run, he moved on to the super capacitor powered LIO, very successful as well. I owned both. Now, he has gone back to traditional AC line powered gear, where you are, with solid engineering, great sound, reliable and easy gear to live with. The new L2 range is already receiving great reviews. If it were me I'd stay the course, which seems to be working very well for you. Do what you do best.

+1

[Danny Richie]

First of all Ron, thanks for responding to me.

I have two thoughts to share.  First, if you read through the various reviews of cherry amps and forum comments by owners, given that buyers and reviewers saying great things about his amps are spread across the country and therefore using power from different grids and probably using different cables as well, I suspect that de facto....Tommy’s statement that he has designed his amps not to need special power, cables, etc., are well supported and focusing his time on a battery option has a low prospect for an actual payback.

FYI, I have had some of Tommy's earlier amps over here some time ago. And I found them to be just as susceptible to changes in power cables and conditioners as any other piece of gear that I'd had over here. In fact this type of amplifier has been more susceptible to what is on the AC line than any other type of gear.

And I have always felt (at least with our products) that if a product can be improved or even if there is a possibility that it can be improved then it is worth spending some time to find out.  Good enough for one guys is good enough for the next isn't really my mentality. I'm driven with a passion to make things sound better.

Second, my personal experience... I tried different power cords and different cables and to my great surprise could hear no difference... which as I noted above is not a unique experience.

That my be quite true. Not all systems will allow such differences to be heard.

[Danny Richie]

To be blunt, I’m skeptical of any system that’s sensitive to minute differences in cables, assuming they are low enough resistance to realize the full potential of the amps (speaker cables, power cords), or of decent quality (interconnects) to get the signal to them.  This is a sign that something’s wrong, such as improper grounding, impedance too low at the destination, impedance too high at the source, inadequate shielding, bad connectors, etc.

If we are being blunt then I would have to say that I am skeptical of any gear made by a manufacturer that hears no difference in any of those things. I wonder if you have heard your own gear. By that I mean, if you make a change that you feel might be an improvement in performance then how do you know if it sounds better or not? If you can't tell the difference in speaker cables then how do you tell how much bias to apply to an opt amp for it to sound its best?

On this subject.... I had a company call me (big well known company) that designs play back software. And they really wanted me to use their playback software on my computer at shows, and as a reference for demo's etc. And they were of coarse offering it for free. They wanted my endorsement. So I asked them what types of DAC's they used during their evaluation process. And what their references were. They sounded puzzled. You mean for D/A conversion, they asked? Yeah, what type of DAC do you use? Ah, I guess its an HP, they replied. HP, I asked? Yeah, just whatever is in the computer, they relied. So you are just using the computer sound card for D/A conversion and playback? Yes, they said. Okay, that was all I needed to know. No thanks. They had no idea how their own product sounded.

If I choose to build some battery powered Cherry Amps, I want to hear them myself first. I want to measure them as well.

I like that statement. I measure everything too, but listening is the final determining factor. In the end, it has to sound good. that is what all of this is about.

I don’t believe tremendous available current is necessary.  It’s not as simple as just hooking up batteries, in the case there’s no DC/DC between them and the amp, but not rocket science either. 

I thought that too as did others that I am close with that built off the grid gear. But then we found big advantages in dynamics and drive when using huge 100 amp hour batteries even when we were only powering a mac Mini computer on it.

Anyway, I’m still wondering if it’s worth the trouble because the Maraschino, for example, is a very high performance amp as-is, and we’ve tested (including lots of listening, of course) with several different power supplies already.

I don't know. I can't answer that for you. What is R & D really worth?

So, if only 2 people will ever buy a battery based power supply, it doesn’t make sense to spend the time/money to develop what will be yet another option, thus complicating the product line.

I don't know. If it sounds better will people want it? First you have to conclude if it sounds better.

For me it is all about if it sounds better or not. It has to sound better or I don't offer it. I sell a lot of kits that are budget oriented as far as price goes. If I felt that they didn't out perform anything else in that price range then I wouldn't offer it. However, I offer upgrades for those kits that include higher quality caps, resistors, connectors, and internal damping material that handles resonance control. It is a pretty significant upgrade in performance but it cost more. Most of my customers spend more to get more. If it wasn't worth it I wouldn't offer it. If it cost more money then it has to be better and worth it.

In this case you might design something that sounds better and it cost less.

We went through something similar with a linear power supply for Maraschino amps.  We sold a few, but interest was light, and it wound up fading away. It was a good power supply, and super heavy for its size, but resulted in lower power output. Other specifications were the same, and so was the sound, except when large peaks while driving difficult speakers (Mags) were too much to handle. Meanwhile our standard 60V 1kW switching supply powered though the same tracks without a sweat!

Sometimes you don't know until you try. Sometimes R & D cost is high and doesn't get you anywhere. Sometimes you find a break through.

You also have to be able to tell the customer how something sounds by comparison. So for instance how did the linear power supply sound compared to the switching power supply.

By the way, what are you using as a reference playback system. Can you provide any pictures of your reference listening system and room?

And I hope this is productive in some way for you. I really would like to help you.

[AmpDesigner333]

FYI, I have had some of Tommy's earlier amps over here some time ago. And I found them to be just as susceptible to changes in power cables and conditioners as any other piece of gear that I'd had over here. In fact this type of amplifier has been more susceptible to what is on the AC line than any other type of gear.

Almost all of our customers that tried fancy power cords and/or power conditioners have said the opposite.  We make it a point to ask.

By “this type of amplifier”, if you’re referring to Class-D, please note that our proprietary designs are very different than typical Class-D amps.

If your system is affected by power cords or conditioners despite tight regulation/decoupling, floating ground, super high PSRR, and proper signal handling, then there may be other issues at hand.

We have a sale going on now for our TL DACs.  They have 4 stages of power conditioning internally, double differential true balanced DC coupled outputs, and an output stage that mimics the transfer function of tubes but doesn't suffer from the noise and other issues with tubes.  Driving Cherry Amps directly with the Cherry DAC DAC (any version) assures no added preamp noise/distortion as well as proper signaling (impedance, voltage level).  For higher performance (and no tube effect), the Cherry DAC DAC HS takes it to the next level with 124dB SNR and <0.0004% THD+N.  That's also on sale, and if you want more information on our available demos or sale prices, just email Support@DigitalAmp.com.  With this type of arrangement, there's not much that can "go wrong", so swapping power cords or adding power conditioning is very unlikely to have any effect, unless there is too much resistance in the mains path.  Same with fancy XLR cables.  This is audio done right, assuming good speakers and a good (reliable) digital audio data source.

[Danny Richie]

If your system is affected by power cords or conditioners despite tight regulation/decoupling, floating ground, super high PSRR, and proper signal handling, then there may be other issues at hand.

Again, your amps were effected by those changes here as well.

We have also found that A/C power conditioning and filtering to be pretty tricky. Too much can cause as much of an issue as not enough. I've tried power cables with a high level of filtering of RFI and EMI plugged straight into the wall on a piece of gear and got fairly good results. But plugged into the balanced power supply it was too much and sucked the upper detail, spacial ques, and life right out of the music. But a power cable with much less filtering characteristics worked great with the balanced power supply.

Too much ERS paper can knock the life right out of a piece of gear too. But a little bit can really do wonders. That stuff is like a RFI sponge.

Sometimes it takes playing with various combinations to get the right balance. And then if you take the system to a show the A/C noise levels are much higher and what worked great here isn't near enough at the show.

We've spent hours at shows swapping cables in an out to find the right balance.

Batteries on everything solves all of that and in most cases sounds better to boot.

So is there any chance we can see pictures of your reference listening system and room?

And I'd be glad to demo one of those DAC DAC's too.

[RonN5]

Danny... I don’t get it.  You are kind of like a dog with a bone that can’t let go... and it’s not your company, or your product... and not even some outrageous claim by Tommy that his customers and reviewers disagree with.

I understand you are passionate about this issue... so a great idea would be for you to buy one of Tommy’s amps, improve it and then see if he is interested in buying your improvements...

Otherwise... it seems like you are trolling him which is out of character with your posts on other topics.

I will say it again... Tommy makes great sounding amps which people all over the country... on different power grids and with different wires are very happy with. 

[Danny Richie]

Danny... I don’t get it.  You are kind of like a dog with a bone that can’t let go... and it’s not your company, or your product... and not even some outrageous claim by Tommy that his customers and reviewers disagree with.

Tommy sent me a message asking me to join in on a thread in his forum where it was being asked about installing tube connectors (one of our products) on his amps.

And in that thread I asked him about a battery powered version of his amps. So he started a new thread on it and linked to it so that the topic would have its own thread.

Otherwise... it seems like you are trolling him which is out of character with your posts on other topics.

Not trolling. I've been trying to put something together with Tommy for a while. I invited him down for LSAF and to come here to GR Research for a visit several times since last summer. He hasn't been able to make it.

[AmpDesigner333]

Tommy sent me a message asking me to join in on a thread in his forum where it was being asked about installing tube connectors (one of our products) on his amps.

And in that thread I asked him about a battery powered version of his amps. So he started a new thread on it and linked to it so that the topic would have its own thread.

Not trolling. I've been trying to put something together with Tommy for a while. I invited him down for LSAF and to come here to GR Research for a visit several times since last summer. He hasn't been able to make it.

Looks like a battery project isn't in the cards at this time.  There are so many other products I'd like to design, and I've been sidetracked before for various reasons.  One reason is technical interest.  Sometimes the lure of a new circuit design is tempting.  There are hidden issues with any project, and something as seemingly simple as running amplifiers from batteries is no exception, especially if they were originally designed for AC power.

I have an expanding product line, and must be careful not to complicate it unnecessarily.  There's also a lot going on behind the scenes.  I'm the kind of guy who works around the clock.

Expectation Bias:  It's a real problem.  That's why I bring up double blind testing and measurement so often.  This is why I kept asking for resistance measurements of Danny's binding posts.  I don't believe in magic.

I rely on my education and experience.  My methodical, scientific approach is the reason that Cherry products are respected.

Doing stuff like swapping XLR cables iteratively and listening for a difference is a waste of time.  Learning engineering principles, the math behind it, and making measurements is time well spent.  Once you understand the science behind it, there's no need to test if water is wet.  Instead, you know what makes a difference.  If you don't understand the science, it's like working in the dark.  You might get lucky, but it's unlikely.  Those with a strong engineering background and education hardly ever fall for snake oil.  There's so much BS going on in cables, too, and it's been that way for decades.  Only now, the internet has made it easier to argue.  The people with crazy pseudo-scientific justifications for non-issues are con artists.  As someone who designs and produces legitimate hardware, I find all the misinformation out there disturbing.

I can write about this stuff all day, but it's late on a Friday night here, and at some point I need to get off the computer.  No, I'm not sitting on it.  I'm almost sleeping on it, though (:

[AmpDesigner333]

Danny... I don’t get it.  You are kind of like a dog with a bone that can’t let go... and it’s not your company, or your product... and not even some outrageous claim by Tommy that his customers and reviewers disagree with.

I understand you are passionate about this issue... so a great idea would be for you to buy one of Tommy’s amps, improve it and then see if he is interested in buying your improvements...

Otherwise... it seems like you are trolling him which is out of character with your posts on other topics.

I will say it again... Tommy makes great sounding amps which people all over the country... on different power grids and with different wires are very happy with.

Thank you, Ron, for your kind words.  Life as a "non-believer" is tough sometimes 

[AmpDesigner333]

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[Freo-1]

Looks like a battery project isn't in the cards at this time.  There are so many other products I'd like to design, and I've been sidetracked before for various reasons.  One reason is technical interest.  Sometimes the lure of a new circuit design is tempting.  There are hidden issues with any project, and something as seemingly simple as running amplifiers from batteries is no exception, especially if they were originally designed for AC power.

I have an expanding product line, and must be careful not to complicate it unnecessarily.  There's also a lot going on behind the scenes.  I'm the kind of guy who works around the clock.

Expectation Bias:  It's a real problem.  That's why I bring up double blind testing and measurement so often.  This is why I kept asking for resistance measurements of Danny's binding posts.  I don't believe in magic.

I rely on my education and experience.  My methodical, scientific approach is the reason that Cherry products are respected.

Doing stuff like swapping XLR cables iteratively and listening for a difference is a waste of time.  Learning engineering principles, the math behind it, and making measurements is time well spent.  Once you understand the science behind it, there's no need to test if water is wet.  Instead, you know what makes a difference.  If you don't understand the science, it's like working in the dark.  You might get lucky, but it's unlikely.  Those with a strong engineering background and education hardly ever fall for snake oil.  There's so much BS going on in cables, too, and it's been that way for decades.  Only now, the internet has made it easier to argue.  The people with crazy pseudo-scientific justifications for non-issues are con artists.  As someone who designs and produces legitimate hardware, I find all the misinformation out there disturbing.

I can write about this stuff all day, but it's late on a Friday night here, and at some point I need to get off the computer.  No, I'm not sitting on it.  I'm almost sleeping on it, though (:

Agree with this assessment. 


My recommendation would be for you to look into making a product that has the DAC and volume control (plus the power amp) in a single unit . The concept of having the DAC and volume control in a single unit makes a lot sense to me.  The interface to the power amp can be simple, and of high quality.  I think there is a big market for this approach, (a la Devialet), especially if it could come in at a lower price point.

[AmpDesigner333]

Agree with this assessment. 


My recommendation would be for you to look into making a product that has the DAC and volume control (plus the power amp) in a single unit . The concept of having the DAC and volume control in a single unit makes a lot sense to me.  The interface to the power amp can be simple, and of high quality.  I think there is a big market for this approach, (a la Devialet), especially if it could come in at a lower price point.

Solid idea, and something we talk about here a lot -- integration.  The Stereo Maraschino was a winner due to a just a bit of integration.  Thanks for your kind post (:

[Danny Richie]

Tommy,

In the end this is all about listening to music. Some of us in the industry are driven to improve how things sound. If listening or listening comparisons are a waste of time for you then that might explain why requests to see any pictures of your listening room and your audio system have gone unanswered.

I don't expect that you would change your views on that stuff because some guy on the Internet told you something different. Unless you come down for a visit and get placed in front of a system that will allow you to hear differences in all of the things that you have sworn can't possibly matter then nothing will ever change for you.

And unless that happens there really isn't any way that I can help you. But I will extend to you an open invitation if you ever change your mind.

[maty]

I agree at 100% with Danny. It is a process of trial and error until you find the maximum attenuation without the dynamics of the music being affected.

Again, your amps were effected by those changes here as well.

We have also found that A/C power conditioning and filtering to be pretty tricky. Too much can cause as much of an issue as not enough. I've tried power cables with a high level of filtering of RFI and EMI plugged straight into the wall on a piece of gear and got fairly good results. But plugged into the balanced power supply it was too much and sucked the upper detail, spacial ques, and life right out of the music. But a power cable with much less filtering characteristics worked great with the balanced power supply...

It is cheaper to use RF/EMI Schaffner inlet filters and Würth 150 kHz ferrites and other tricks.

[maty]

Some time ago I solved the problems with the terrible electrical grid that arrives at my house. I only have one left: when the voltage exceeds 238 Vac, the sound gets worse. When it is close to 230 Vac my second audio system sounds amazing.

[AmpDesigner333]

Danny,
Have you tried the Rane PI14 processor in your system?

[maty]

Question: how much PSRR have your class-D amps? Numbers.

Maraschino

https://www.cherryamp.com/maraschino

I cant not see the specs.


MEGAschino MK2

https://www.cherryamp.com/dac-home

[AmpDesigner333]

Question: how much PSRR have your class-D amps? Numbers.
Maraschino
https://www.cherryamp.com/maraschino
I cant not see the specs.
MEGAschino MK2
https://www.cherryamp.com/dac-home

What manufacturer shows PSRR in their specifications?  I’m not selling amp chips, but there are chips sold with my technology in them (:

Don’t know exact PSRR off the top of my head, but likely 60-80dB mid-band.  The Maraschino also runs from a regulated supply. The ripple is way out of band.  It’s ultra quiet even at 20kHz.  For the MEGA, the ripple is where PSRR is maxed out, so THD at high power is good (low) on both sides of the spectrum.

Somewhere, I have a photo of the MEGA MK2’s noise floor FFT.  It’s amazing!!  Pretty level at -140dB with -60dB stim.  SNR is the ultimate “proof in the pudding” at about 120dB, so you know the power supply noise isn’t getting through!  It’s a solid design.  This also doesn’t involve the usual chokingly high feedback levels and low phase margins of other Class-D amps.

I’ll be pretty busy over the next few weeks with the Cherry Summer Sale.   Some real bargains on the list.  Email Support@DigitalAmp.com to get it.  We also had a surprisingly huge response to our newsletter announcing the sale!  Looks like being honest and hard working is starting to pay off. Thanks.

[maty]

In Hi-Fi or High-End no one. In professional audio, some mention PSRR and CMRR.

With high PSRR the devices are much less sensitive to the change of the power cable, that is why I asked. And, above all, to the oscillations in the quality of the electrical power supply.

Have you thought about trying to add a RF/EMI Schaffner filter? FN-9244B



BTW, today Archimago: http://archimago.blogspot.com/2019/06/listening-fully-battery-powered.html

Very cheap and old class-D technology. Yeeco - TI TPA3116D2, TalentCell 12V battery.

I agree 100% with him:

It's rather sad and maddening that in 2019, the record companies don't seem to understand that the poor sound quality of these recordings are likely hurting sales and driving music fans away from artists and their music in general. Despite hi-fi technology improving over the years, the technical qualities of mainstream music have as a whole diminished...

I have been denouncing it for years.

[Jonathon Janusz]

Looks like a battery project isn't in the cards at this time.

It is too bad this won't work out at this time then.  Thanks, Tommy, for at least entertaining the idea and letting what I thought was an interesting conversation gel its way to get here.

Expectation Bias:  It's a real problem.  That's why I bring up double blind testing and measurement so often.  This is why I kept asking for resistance measurements of Danny's binding posts.  I don't believe in magic.

I rely on my education and experience.  My methodical, scientific approach is the reason that Cherry products are respected.

Doing stuff like swapping XLR cables iteratively and listening for a difference is a waste of time.  Learning engineering principles, the math behind it, and making measurements is time well spent.  Once you understand the science behind it, there's no need to test if water is wet.  Instead, you know what makes a difference.  If you don't understand the science, it's like working in the dark.  You might get lucky, but it's unlikely.  Those with a strong engineering background and education hardly ever fall for snake oil.  There's so much BS going on in cables, too, and it's been that way for decades.  Only now, the internet has made it easier to argue.  The people with crazy pseudo-scientific justifications for non-issues are con artists.  As someone who designs and produces legitimate hardware, I find all the misinformation out there disturbing.

In the end this is all about listening to music. Some of us in the industry are driven to improve how things sound. If listening or listening comparisons are a waste of time for you then that might explain why requests to see any pictures of your listening room and your audio system have gone unanswered.

I don't expect that you would change your views on that stuff because some guy on the Internet told you something different. Unless you come down for a visit and get placed in front of a system that will allow you to hear differences in all of the things that you have sworn can't possibly matter then nothing will ever change for you.

And unless that happens there really isn't any way that I can help you. But I will extend to you an open invitation if you ever change your mind.

Thank you both for articulating well the lines along which each of you work in pursuing a shared interest in audio.

Have you tried the Rane PI14 processor in your system?

I'll mark this as to where the topic officially jumped the shark.  I had to look this up to see what this was.  Another company I've made friends at in a completely different industry is also good at this sort of thing, generally as an April Fools joke each year for their marketing/social media department to play around with their customers.  I'd just hope something that was (I hope) intended by Rane as all in good fun isn't generally turned into something that is decidedly not in good fun.

Thanks again for an interesting topic!

Jon