Introducing the New HiFi Miser Forum-As discussed by Andre Marc

[Blizzard]

In fact, as I pointed out, Ian Robinson sent me a detailed overview of his design for Redgum amps, and it was met with total
and utter silence.

I bet if he were to come on the forum, and personally clear up misconceptions, he would gain more respect for his products, and it would have reversed the situation. In the end readers of the thread would walk away confident that Redgum products are solidly engineered, and the products to buy.

I think this day in age, as a small manufacturer, you must be active on the forums.

It's human nature to criticize. You simply must be prepared for this, and ready to defend your product when situations like this arise.

 

[JackD201]

Hi Jack. Thermal compound is mandatory between the transistor and its heatsink to improve heat transfer as you mention. Even the most novice DIY amp builders know this. And certainly no commercial amp ships without some version of this.

The need for the compound is sharply increased in most amps that require electrical isolation of the output transistor body. The transistor metal tab connects to one of its pins which is usually going directly to power supply positive and negative rails. Without isolation you would simply short out the power supply! Some type of isolation is then necessary there in the form of mylar, etc. Once there, you now you have two surfaces that can reduce thermal transfer. Thermal compound therefore is used on both sides of the electrical isolator making for some messy job replacing the transistors!

I think the only time I have seen no paste was in cheap all-in-one hifi boxes of 1970s.

There was no mystery there anyway. The reason the unit doesn't overheat is due to its large heatsink relative to its modest output power. The concern we had was not that but rather the heat rising into the chassis and elevating the temps of the capacitor and thereby potentially shortening their life.

Gotta give me props for getting you to openly recognize the transistor heat output to heatsink mass ratio being adequate. I do know what a collector is That's a lot of surface area to transfer the heat to the air outside.

There are many products of more power with sinks inside with nothing but tiny vents on the casework tops to let heat naturally rise up and out which generate more heat and power than this little guy. So, can it be said that this admittedly odd, klunky and I'll just go out and say it, inelegant layout solution, is enough to not let the amp go off into thermal hell? You could plop this thing upside down and reverse the graphics after all and use much less metal. Then again, it wouldn't look as cool would it. Metaxas has got it's heatsinks underneath too. I'll leave that to these designers. Bottom line is odd as they are, if they sound good and are actually reliable, it's their call.

 

[nc42acc]

Blizzard can you elaborate on what you are working on? Maybe start another thread?

Once I get my products to market, I can't wait for opportunities like this to arise.

 

[DaveyF]

As some of you may know, I own an older ARC D70Mk2. This amp, which is typical of the design from ARC for many years ( and is IMO one of WZJ"s best), has a tube cage that fits over all of the tubes and the electronics. Here's the thing, on the tube cage, there is a placard that states: " WARNING This unit contains voltages which may be lethal---Do not operate with covers removed--". Problem is that if one is to follow that instruction, the tubes burn up rapidly and I'm sure the life of the other electronics is greatly shortened. The heat generated is too much to escape the perforated cage efficiently. Is this a design flaw....yes and not really, as the cage can be easily removed. However, how many people have owned these type of amps over the years and questioned why the tube life has been short or another failure has occurred inside the amp. If I remember, the ARC amps of yore were notorious for failure...and yet they are deservedly popular and sought after. One of the members here actually owns the enormous ARC D250...how many tubes under the hood!! My point, even with the knowledge that the amp may be 'fragile'...the sound was so much ahead of everything else at the time, people would still make the acquisition.

 

[Blizzard]

Blizzard can you elaborate on what you are working on? Maybe start another thread?

I already started a thread:

http://www.whatsbestforum.com/showthread.php?18648-The-best-way-possible-to-build-an-active-system

 

[nc42acc]

Got it. Thanks

I already started a thread:

http://www.whatsbestforum.com/showthread.php?18648-The-best-way-possible-to-build-an-active-system

 

[zztop7]

Engineering Detail

Many times in observing my properly done engineering work, people comment on my attention to detail: "Why are you doing that, no one will ever see it, no one will ever know?"
I respond: "I will know."
zz

 

[DaveyF]

Many times in observing my properly done engineering work, people comment on my attention to detail: "Why are you doing that, no one will ever see it, no one will ever know?"
I respond: "I will know."
zz

That's the attitude that we all hope goes into the quality control of everything that we own ( and in fact try to accomplish)...too bad it isn't that common.

 

[DaveC]

I agree that it's not pleasant to have your products criticized, especially in a public form. However the way I look at it, a situation like this presents the perfect opportunity for the manufacturer to chime in and explain why their products are engineered the way they are. This will clear up any misconceptions from "armchair engineers" as well as reinforce to the public that not only is the product solidly engineered, the designer also stands behind his products.

Once I get my products to market, I can't wait for opportunities like this to arise.

Not everyone has time to waste correcting misunderstandings and justifying design decisions on the internet. And what if the designer is unaware of the discussion? I don't think it's reasonable to expect this at all.

 

[Blizzard]

Not everyone has time to waste correcting misunderstandings and justifying design decisions on the internet. And what if the designer is unaware of the discussion? I don't think it's reasonable to expect this at all.

Maybe not. But this is just human nature. It's been this way since the beginning of time. When you produce a product, you must expect criticism. And in today's world with so much internet based discussion and business, I think it's essential to be aware what's happening on the forums. Especially in the tight knit world of high end audio.

For example, if someone was the criticize the purity of the copper used in one of your cables, I'm sure you would be able to clear up the misconception right away. Then in the end once you clarified things, you would probably walk away with several more orders than you would of had before the criticism.

I see this as the perfect opportunity to educate the public in the cleverness of your engineering. The best advertising possible.

 

[Johnny Vinyl]

Maybe not. But this is just human nature. It's been this way since the beginning of time. When you produce a product, you must expect criticism. And in today's world with so much internet based discussion and business, I think it's essential to be aware what's happening on the forums. Especially in the tight knit world of high end audio.

For example, if someone was the criticize the purity of the copper used in one of your cables, I'm sure you would be able to clear up the misconception right away.

But it wasn't the manufacturer that introduced the product. Had it been, then all criticism would have been fair game.

 

[kach22i]

In fact, as I pointed out, Ian Robinson sent me a detailed overview of his design for Redgum amps, and it was met with total
and utter silence.

Speaking for myself, I did not immediately reply out of politeness.

Mr. Robinson obviously didn't want to explain the design, and only offered his assurances.

That is hardly an explanation containing a concept or a goal of some kind - let alone a technical explanation.

Trust me, I made the effort to see into his mind with sketches, and my own explanations about it possibly functioning as a mass-sink in lieu of a traditional heatsink.

I didn't, and the forum didn't get any explanation along these lines in return for our efforts and attempts to understand how the design works.

In fact, only a few posts ago JackD201 is calling it a "collector" - I assume this is progress being made.

Had Mr. Robinson called it a "collector" or "mass-sink" in lieu of a "heatsink", then we would at least know that he understands how his own design works.

Right now I'm not sure what to make of it, because the person calling himself a professional reviewer and industry expert admits to lacking a technical background which could aid us in this situation.

Now, about DaveC's remarks...................

That pic where the rectifier is supposed to be touching an electrolytic cap looks suspect to me, I do not believe they are touching. If you look down there is no solder pad for the rectifier right next to the cap. And it's not exactly esoteric knowledge that electrolytic caps shouldn't touch parts that get hot. IMO this is a good example of armchair engineering gone bad, and there were many more like it. I think some of the criticism was based on incorrect assumptions and it certainly went way too far, for example the guy who said everything would reach the same temps internally, this is just wrong. I don't think criticism should not be allowed

I've put in bold a few things which may deserve some kind of further explanation or support of some kind by DaveC- in my opinion.

RE: armchair engineering gone bad...............only if you are right about the two parts NOT touching. I'm going to assume that the person taking the pictures had a better vantage point than us and made the correct call. Second guessing someone else's observations without cracking open a unit yourself is non-scientific to say the least.

RE: same temps internally................the parts are all in the sealed box together, sort of like being in the same bath water together (air and water each following the rules of fluid dynamics). Some parts will generate heat and radiate it into the air, other parts not as hot will absorb that heat out of the air. One of the rules of thermal dynamics is that nature seeks an equilibrium, or words to that effect.

I can see how that comment was made in light of the whole "collector" or "mass-sink" description being missing in Mr. Robinson's explanation of how the thing works.

We in the forum in fact are still struggling to understand this design in the void the review and the designer have created.

..............................................................

Really isn't this tiring?

Just tell us how it's suppose to work instead of telling us not to worry about it.

Some of us just want to know how things work, is that so bad?

 

[Blizzard]

But it wasn't the manufacturer that introduced the product. Had it been, then all criticism would have been fair game.

Yes but it doesn't matter who brings up the topic, people are gonna criticize. I don't think there's been 1 topic I've brought up on this forum yet that didn't come under attack. But if you make you point so clear that the criticizers become lost for words, and clearly defeated, the issue can be considered resolved.

 

[Andre Marc]

Speaking for myself, I did not immediately reply out of politeness.

Mr. Robinson obviously didn't want to explain the design, and only offered his assurances.

That is hardly an explanation containing a concept or a goal of some kind - let alone a technical explanation.

Trust me, I made the effort to see into his mind with sketches, and my own explanations about it possibly functioning as a mass-sink in lieu of a traditional heatsink.

I didn't, and the forum didn't get any explanation along these lines in return for our efforts and attempts to understand how the design works.

In fact, only a few posts ago JackD201 is calling it a "collector" - I assume this is progress being made.

Had Mr. Robinson called it a "collector" or "mass-sink" in lieu of a "heatsink", then we would at least know that he understands how his own design works.

Right now I'm not sure what to make of it, because the person calling himself a professional reviewer and industry expert admits to lacking a technical background which could aid us in this situation.

Now, about DaveC's remarks...................


I've put in bold a few things which may deserve some kind of further explanation or support of some kind - in my opinion.

RE: armchair engineering gone bad...............only if you are right about the two parts NOT touching. I'm going to assume that the person taking the pictures had a better vantage point than us and made the correct call. Second guessing someone else's observations without cracking open a unit yourself is non-scientific to say the least.

RE: same temps internally................the parts are all in the sealed box together, sort of like being in the same bath water together (air and water each following the rules of fluid dynamics). Some parts will generate heat and radiate it into the air, other parts not as hot will absorb that heat out of the air. One of the rules of thermal dynamics is that nature seeks an equilibrium, or words to that effect.

I can see how that comment was made in light of the whole "collector" or "mass-sink" description being missing in Mr. Robinson's explanation of how the thing works.

We in the forum in fact are still struggling to understand this design in the void the review and the designer have created.

..............................................................

Really isn't this tiring?

Just tell us how it's suppose to work instead of telling us not to worry about it.

Some of us just want to know how things work, is that so bad?

My job is to tell you how the product performs..how it sounds, and the ergonomics.

Harry Pearson would not know a capacitor from a resistor and he was the exalted one for 45 years.

Technical knowledge has absolutely, and utterly nothing to do with listening.

 

[Andre Marc]

Yes but it doesn't matter who brings up the topic, people are gonna criticize. I don't think there's been 1 topic I've brought up on this forum yet that didn't come under attack. But if you make you point so clear that the criticizers become lost for words, and clearly defeated, the issue can be considered resolved.

Criticizing, from afar, using photos, conjecture, insinuations, and presumptions, with an anonymous moniker, is cowardly.
it is even worse when you have no interest in the product.

Being CURIOUS, is another thing.

 

[Blizzard]

My job is to tell you how the product performs..how it sounds, and the ergonomics.

Harry Pearson would not know a capacitor from a resistor and he was the exalted one for 45 years.

Technical knowledge has absolutely, and utterly nothing to do with listening.

My take is, after the criticism occurred would have been a great time to e-mail a link of the thread to Ian so he can explain the design, and reassure the readers that his engineering is solid and justified. Nobody will be able to do a better job at that than the engineer.

 

[Andre Marc]

My take is, after the criticism occurred would have been a great time to e-mail a link of the thread to Ian so he can explain the design, and reassure the readers that his engineering is solid and justified. Nobody will be able to do a better job at that than the engineer.

No. Not one of that nasty bunch had one iota of interest in a $2500 amp. They can email Redgum with any questions they may have. Or not.

 

[Blizzard]

No. Not one of that nasty bunch had one iota of interest in a $2500 amp. They can email Redgum with any questions they may have. Or not.

This would be for the sake of everyone else that read the thread. This probably would have reversed the situation, and resulted in a pile of sales, rather than all of the negative publicity.

 

[Johnny Vinyl]

No. Not one of that nasty bunch had one iota of interest in a $2500 amp. They can email Redgum with any questions they may have. Or not.

Bingo.

The only reason this was attacked is because the heatsinks are at the bottom. None of your other product introductions saw the light of day as much as this one.

 

[nc42acc]

I am curious about the key on the front. Is this the on/off switch? I personally like the styling of their products. I cannot comment on how they sound.