Cherry Amplifier (R) ---- What We're About

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AmpDesigner333

Re: Digital Amplifier Company DAC4800A and Cherry amps
« Reply #700 on: 13 Mar 2018, 03:44 am »
AmpDesigner 333

I like your philosophy and hope you will succeed in your creative venture! And when you do, don't forget that customer service is one of the pillars to a successful audio business! Krell started as a backyard project to beat the Big Boys and succeeded to become one of the most successful audio brands but they forgot about their customers once they tasted the dizzy heights of success! I had an experience with their customer service and speak from the perspective of my experience.

I know how hard it is to convince the consumer that you have a great product in hand, beyond the marketing hyperbole!

Best Regards
Dennis
Dennis,

Please take a look at the first post on this thread!  I updated it after more than a DECADE! It was my first post on Audio Circle....

You were (and are) correct!  Your advice was as natural to follow for us as waking up in the morning. We realize the customer is who puts the food on our tables. The customer is why we exist.  They are everything to us!  You are certainly a smart and genuine man. Thanks for your kind words way back when hardly anyone was aware of Cherry Amplifier (R)!

-Tommy O

ohenry

Re: Cherry Amplifier (R) ---- What We're About
« Reply #701 on: 13 Mar 2018, 05:15 am »
Tommy, it's always enriching to see someone thrive.  And looking back as you suggested, really brings it home.  Nice work and be proud.   :D

AmpDesigner333

Re: Cherry Amplifier (R) ---- What We're About
« Reply #702 on: 13 Mar 2018, 01:55 pm »
Tommy, it's always enriching to see someone thrive.  And looking back as you suggested, really brings it home.  Nice work and be proud.   :D
Thanks for your kind words.  Intelligent people like you see beyond the marketing and understand true value.  Thanks also for taking the time to check out my modified "first post" (original version included) and posting your thoughts here!

-Tommy O

AmpDesigner333

Re: Cherry Amplifier (R) ---- What We're About
« Reply #703 on: 14 Mar 2018, 08:09 pm »
Less than 12 days left:
http://kck.st/2CH4sLB

We now have a Digital Audio Bundle!  Take a look at the rewards to see what I'm talking about....

AmpDesigner333

Calculating SNR at 1W
« Reply #704 on: 19 Mar 2018, 06:26 am »
SNR at 1W can be calculated from SNR at rated power.  This is not just for Cherry Amplifier (R) products, but for any amplifier.

If we know the signal level and the SNR, we can calculate the noise level.  This is typically A-weighted, by the way, but not important to the math....

SNR is the ratio of signal to noise, or signal/noise.  These are voltage levels.  Units must match, and we use volts.  SNR = 20 * log(signal/noise).  Since there is more signal than noise, SNR is positive.  If it were noise/signal, the result would be negative, due to the log function.

We start by reversing the log function to get the actual ratio in straight scalar units (no units, actually).  So, we're "un-doing the dB", going from exponential scale to linear scale.

Let's say SNR is 120dB (MEGAschino, Maraschino).  This means 6 = log (x), x being SNR as a linear scalar.  10^6 is 1,000,000.  So, if the signal is 1V, the noise would be 1/1,000,000 V, or 1uV.

Let's also say the rated power is 400W into 4 ohms (KING Maraschino).  Power is V^2/R in this case, so V = sqrt(1600V^2) = 40V.  So, in this case, noise is 40uV.

Now, what is it at 1W (into 4 ohms)?  Well, we know the noise voltage, and 1W is sqrt(4V^2) = 2V, so SNR = 20 * (2V/40uV) = 94dB.

The reverse also works, so if you know SNR at 1W, you can calculate it for rated power.  Almost every amp manufacturer states SNR at rated power, by the way.  Thanks.

-Tommy O

AmpDesigner333

Re: Cherry Amplifier (R) ---- What We're About
« Reply #705 on: 19 Mar 2018, 06:35 am »
What....  ....does Digital Amplifier Company consider reasonable or acceptable in Class-D amplifiers?
The higher the better.  Class-D is just a topology.  What I (representing Digital Amp Co) consider "reasonable or acceptable" is not based on 1W.  It's based on max output of the amp, and it's 110dB or more for anything that's considered a "high performance" amplifier.  Thanks again.

maty

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #706 on: 19 Mar 2018, 12:36 pm »
From the other thread, better here.

I know the maths but I have found too often that the data advertised by the manufacturers do not coincide with the independent measurements. It was something I already knew with class AB but I was surprised that it also happened with Class D amplifiers.

Same problems with speakers manufacturers: sensitivity and nominal impedance. And then some complain that the speakers do not sound as good as many say. Or sell them accompanied by amplifiers that do not have the necessary power to sound with all their splendor.

https://www.cherryamp.com/the-stm-specs

Gain: 22dB

Frequency Response: 0 Hz to >100 kHz

Power Efficiency: 95% !!!!


Very good specs.

And thank you very much.

maty

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #707 on: 19 Mar 2018, 12:37 pm »
Quote
The reverse also works, so if you know SNR at 1W, you can calculate it for rated power.  Almost every amp manufacturer states SNR at rated power, by the way.  Thanks.

I know I know. As Nelson Pass always says, the first watt is very important. To compare is very good.

The most realistic measurements are with 8 watts - 10 watts I think.

With class AB amplifiers, I like > 88 dB at 1 watt "A weighted" with 8 Ohms load. To play very good recordings. Better 90 dB off course, but after so many measurements that I have seen lately I lowered the bar.

In class D one always expects better specifications, hence my surprise with others manufactures.

maty

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #708 on: 19 Mar 2018, 12:38 pm »
To finish,

The measures are very important but... Years ago, when the DC, noise, interferences... in my house mains had me bitter I decided to buy a second-hand amplifier (only €118 at home) to implement solutions and improvements. Before giving the purchase order I duly informed myself.

https://www.soundandvision.com/content/marantz-sr4500-av-receiver-ht-labs-measures

After the internal improvements I made and my problems solved, I have been able to appreciate the excellent recordings I usually listen to. The measurements I suppose will be the same -with much less noise- but the sound is much better than when it came to my hands.

In short, that measurements are a necessary but not sufficient condition. There are more factors to take into account to get a good sound, not to mention the room conditioning.

AmpDesigner333

Re: Cherry Amplifier (R) ---- What We're About
« Reply #709 on: 22 Mar 2018, 11:36 am »
This weekend is the last one for our new Kickstarter.  Time to get involved if you haven't already.  Our backers provide the funds for new product development and get rewarded generously as a result.

Here's the link (please help us spread the word by posting this link on social media):
http://kck.st/2CH4sLB

We also added a special new reward today.  It's an "only one available" pair of amps.  See if you can spot it (:

Thanks as always!

AmpDesigner333

Sunday is the last full day to get special pricing
« Reply #710 on: 22 Mar 2018, 01:51 pm »
This weekend is the last one for our new Kickstarter.  Time to get involved if you haven't already.  Our backers provide the funds for new product development and get rewarded generously as a result.

Here's the link (please help us spread the word by posting this link on social media):
http://kck.st/2CH4sLB

We also added a special new reward today.  It's an "only one available" pair of amps.  See if you can spot it (:

Thanks as always!
Last full day for the program is this Sunday, the 25th.  Thanks again.

AmpDesigner333

New MEGA Review
« Reply #711 on: 24 Mar 2018, 01:54 pm »
“MEGAschino may very well be the most dynamic amplifier ever built – outing the Golden as my favorite in this area”
    - Jeremy R. Kipnis / Kipnis Studios
http://www.jeremykipnis.com/MEGAschino_Review_-_03_18.html

maty

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Re: Calculating SNR at 1W
« Reply #712 on: 25 Mar 2018, 10:53 am »
SNR at 1W can be calculated from SNR at rated power.  This is not just for Cherry Amplifier (R) products, but for any amplifier.

If we know the signal level and the SNR, we can calculate the noise level.  This is typically A-weighted, by the way, but not important to the math....

SNR is the ratio of signal to noise, or signal/noise.  These are voltage levels.  Units must match, and we use volts.  SNR = 20 * log(signal/noise).  Since there is more signal than noise, SNR is positive.  If it were noise/signal, the result would be negative, due to the log function.

We start by reversing the log function to get the actual ratio in straight scalar units (no units, actually).  So, we're "un-doing the dB", going from exponential scale to linear scale.

Let's say SNR is 120dB (MEGAschino, Maraschino).  This means 6 = log (x), x being SNR as a linear scalar.  10^6 is 1,000,000.  So, if the signal is 1V, the noise would be 1/1,000,000 V, or 1uV.

Let's also say the rated power is 400W into 4 ohms (KING Maraschino).  Power is V^2/R in this case, so V = sqrt(1600V^2) = 40V.  So, in this case, noise is 40uV.

Now, what is it at 1W (into 4 ohms)?  Well, we know the noise voltage, and 1W is sqrt(4V^2) = 2V, so SNR = 20 * (2V/40uV) = 94dB.

The reverse also works, so if you know SNR at 1W, you can calculate it for rated power.  Almost every amp manufacturer states SNR at rated power, by the way.  Thanks.

-Tommy O


SNR calculation. Easy and fast.

400 watts/4 Ohms -> SNR: 120dB. V=40v


with 1 watts/4 Ohms V=2v

 -> 120dB - 20log(40v/2v) = 120dB - 26dB = 94 dB


to compare

1 watts/8 Ohms -> 91 dB


With class AB, 91 dB is very good. With class D is only good, I think.

OzarkTom

Re: Calculating SNR at 1W
« Reply #713 on: 25 Mar 2018, 03:07 pm »

SNR calculation. Easy and fast.

400 watts/4 Ohms -> SNR: 120dB. V=40v


with 1 watts/4 Ohms V=2v

 -> 120dB - 20log(40v/2v) = 120dB - 26dB = 94 dB


to compare

1 watts/8 Ohms -> 91 dB


With class AB, 91 dB is very good. With class D is only good, I think.

The proof is in the listening Maty. I have had a lot of Class D amps here and the Cherries has beat them all by quite a bit. :thumb:

AmpDesigner333

Re: Calculating SNR at 1W
« Reply #714 on: 25 Mar 2018, 03:08 pm »

SNR calculation. Easy and fast.

400 watts/4 Ohms -> SNR: 120dB. V=40v


with 1 watts/4 Ohms V=2v

 -> 120dB - 20log(40v/2v) = 120dB - 26dB = 94 dB


to compare

1 watts/8 Ohms -> 91 dB


With class AB, 91 dB is very good. With class D is only good, I think.
Although our specifications are admirable, they only tell part of the story.  I'm guessing you've never HEARD a Cherry Amplifier (R)....

You should take a look at the very first post in this thread.  I explain why the Cherry Amp SOUND is better than non-Cherry amps (Class-D or not).

There are only a few hours left of our MEGA Intro Kickstarter (http://kck.st/2CH4sLB).  How about picking up a MEGA to see/hear for yourself?  Then you can hear how good Class-D can SOUND.  If for some odd reason you decide not to keep your Cherry Amp, you can easily sell it, probably for a decent profit considering the Kickstarter price.

Thanks again (:

-Tommy O

maty

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #715 on: 25 Mar 2018, 03:12 pm »
I have nothing against this amplifier. For example, the efficiency of 95% giving so much power is an engineering prodigy.

The problem is in the other brands that buy modules designed by others and spoil the specifications and not by little.

And then there are revisions in Stereophile and they are silent in the face of the obvious.

AmpDesigner333

Re: Cherry Amplifier (R) ---- What We're About
« Reply #716 on: 25 Mar 2018, 03:15 pm »
I have nothing against this amplifier. For example, the efficiency of 95% giving so much power is an engineering prodigy.

The problem is in the other brands that buy modules designed by others and spoil the specifications and not by little.

And then there are revisions in Stereophile and they are silent in the face of the obvious.
We are discussing a review with Stereophile, but since we don't advertise there, it might be a while.  Thank for your kind post.

OzarkTom

Re: Cherry Amplifier (R) ---- What We're About
« Reply #717 on: 25 Mar 2018, 04:43 pm »
We are discussing a review with Stereophile, but since we don't advertise there, it might be a while.  Thank for your kind post.

Tom Goetz sent a pair of speakers and bought an ad, never got one review. Too much politics.

sumoking

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #718 on: 25 Mar 2018, 05:25 pm »
With social media, AC, and other forums, Stereophile has lost its power.  I have been out the game for about 12 years and came back in a couple years ago and got a subscription. It did nothing for me.  At this point, meeting folks on AC, going to audio shows and listening to the products is the only way to make sound purchasing decisions in the current era.

I would never just buy a product cause of a review.  The point is their is so much free information from people who are knowldegable and just want the best sound.  Stereophile reviewers are just way to influenced by the mighty $$$.

I understand the need as a manufacturer to want to get their product reviewed and it will probably help get a few sales, but that's not where the future lies.  I wonder how many subscribers they have? vs. 5 years ago? vs 10 years ago? vs 15?

LarryD56

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Re: Cherry Amplifier (R) ---- What We're About
« Reply #719 on: 25 Mar 2018, 06:17 pm »
I bought my first Cherry amplifier while looking online for a high powered amp to run my newly acquired vintage Infinity speakers. Saw one for sale, checked out the specs, then I went to the forums to see what owners had to say about their amps. Reading articles are a good introduction, but to me, I want to know what owners think.

Larry D.