Modwright KWI 200 Hybrid-- A Pipe Dream?

Joe Frances · « **Reply #40 on:** 17 Apr 2019, 02:45 am »

Quote from: The Rang on 10 Aug 2018, 02:30 am

That’s one of the reasons I bought the KWI 200 over a couple of other worthy candidates.
I wanted the simplest amp possible, where ALL the money and effort is spent on the amp.
No DAC, no tuner, no meters or a bunch of buttons I’d never use etc.

Yea, but you gotta love those lovely dials....

jriggy · « **Reply #41 on:** 17 Apr 2019, 12:40 pm »

Quote from: FWS5 on 16 Apr 2019, 12:17 pm

Wow - OK got it.
I'll shut up and go away then - all you had to say. You guys are apparently way too smart for a dummy like me to interact with.

I've not designed electronics, I'll leave that to Dan. I only have ideas for the case which I do have experience with. My ideas are quite simple and version 1 shouldnt add much more cost than a piece of glass. Version 2 is actually fairly simple and would add some cost but probably not much. The bigger problem is having enough space to implement it. It takes the same footprint as the current board but obviously would need space below. In either case there is of course the redesign cost.

Several times in the past I have approached other companies whose products I am interested in about potential design changes where the company found my idea worthwhile and did make those changes and/or incorporated them as a new model. Thats a fact - I have and use them daily..

I will say that I rethought posting this here because I had just emailed Dan about this and hadnt given him opportunity to respond first but only after I hit the post button. Sorry Dan. And sorry to upset the status quo.

As previously stated, I'll take my thoughts and ideas and go away. Cary on...

FWS

AC is not like other ‘public’ message boards. You may notice that there are ‘introduction’ suggestions for new members, soMe specific rules, as well that each manufacturer pays to have their own ‘Circle’ here. That and the rules of conduct do indeed create a place different from other forums.
You’re new, and besides maybe blowing Dans announcement of his new product, you didn’t really do anything wrong, so don’t best yourself up or just leave after two posts...

But I think there is still much more that goes into design changes than you may be realizing. Even redesigning a chassis lid for the cnc guys to accommodate your ambitious idea of some sort of mechanized convenience feature to reveal and conceal tubes for the rare couple people out there that don’t like to look at them, is work and money that will add to the cost of the unit. The mechanized feature certainly sound cool but knowing Dans products, look and price points, it seems like an idea better suited for maybe Mcintosh or the like...

But I’d love to hear about these pieces in your system that you assisted with chassis design on. Sound like some potentially interesting. Feel free to find the right circle and post some of your design work!

RDavidson · « **Reply #42 on:** 17 Apr 2019, 02:59 pm »

I don't think he assisted on chassis design as much as offered ideas that the manufacturers decided to implement. I may be wrong. I come from a professional design, engineering, and manufacturing background. It takes more than sketches to do things. His suggestion rubbed me the wrong way. Like...I have a great idea. I made some sketches. I don't know your goals with the project or really what it'd take to do it, but my idea is great and theoretically simple, so it should be easy to just make it happen. I've run into this frequently...so it's a little bit of a sore spot for me. Sharing ideas is great. But there's a line where one should step away and leave it to the pros, especially if you don't have real stake in the matter. Know what I mean? I don't think Dan needs help in this area. He has built his own esthetic / functional "brand" already. A mechanized tube display is indeed more along the lines of McIntosh and others. But anyway...

I'm looking forward to Dan sharing his newest creation. I've considered the KWI200 many times.

jriggy · « **Reply #43 on:** 17 Apr 2019, 04:55 pm »

Yes, I do know what you mean..and I completely agree. You actually stated a couple things I left out of my response.

modwright · « **Reply #44 on:** 17 Apr 2019, 11:55 pm »

Hi Guys, first of all, I welcome suggestions and feedback, even if I disagree. So, please don't be afraid to express opinions, suggestions, etc. At worst I will disagree or explain why it is not a good idea. At best, it is an appreciated suggestion that I had not thought of!

So the unit was a bit hit at Axpona!

Tubes are exposed to reject heat. I will add a tube guard/shield/cage to meet CE requirements for the EU. I am thinking of a clear acrylic block to house the tubes, cantilevered off the back of the enclosure that can be removed with two thumb screws for ease in tube swapping.

Pricing: $8495
Options: Phono optional ($350 add), user-installable.
DAC: None will be available because technology changes too fast!
HP out I have not decided about.
Home Theater Bypass.
XLR inputs (not likely fully balanced because the preamp section is single ended).

Specs:
225W into 8 ohms/ 350W+ into 8 ohms.
Output stage of the 150SE Reference Amp (BJT).
Tube preamp stage (6922/6dj8/7308 based).
17"Wx17"Dx5.5"H

Photos to follow tomorrow....sorry guys but I am still recovering!

Thanks,

Dan

modwright · « **Reply #45 on:** 18 Apr 2019, 11:32 pm »

KWH 225i Photos as promised!

Yes, I know that the logo in the cover is reversed. My machinist didn't bend the metal in the right direction, so for the proto covers, the logo is mirrored

Please let me know what you think!

Thanks,

Dan Wright

jtwrace · « **Reply #46 on:** 19 Apr 2019, 02:10 am »

Just curious why all wires seem to be twisted other than the transformer wires.

RDavidson · « **Reply #47 on:** 19 Apr 2019, 02:46 am »

Nice! Definitely carries the Modwright family DNA.
The only thing I'd maybe change, esthetically, are the heat sink windows on the sides. I think they look great on the top and I assume there are corresponding windows on the bottom for air flow-thru. I think they're unnecessary on the sides and make the cover seem less solid and rather flimsy and busy. Removing those would clean up the look and also make the unit more comfortable to carry as well as move in and out of a rack.

FWS5 · « **Reply #48 on:** 19 Apr 2019, 11:37 am »

Ideas are great and all, but I would let Dan design HISproduct.

FWS5 · « **Reply #49 on:** 19 Apr 2019, 11:49 am »

I like the side cut outs but my first impression was the same as RDavidson. I'm good as is but IF I MAY suggest, having the side cut outs extend only half way down from the top or equal to width of top vents whichever looks best. This allows for a sturdier case/look keeping the original design aesthetic and still allows additional cooling.

FWS

modwright · « **Reply #50 on:** 19 Apr 2019, 04:21 pm »

First of all, twisted pair wires. This is always done when power or signal wires are used, to prevent noise. Power/ground twisted pairs and signal/ground twisted pairs is an effective and ideal way of shielding and noise suppression.

As for the exposed heat sinks and side windows, it is ALL about maximizing ventilation and cooling of the output devices. to be honest, you will not see the sides of the unit anyhow, likely, but even so, there MUST be the greatest amount of exposed heatsink are possible! The best sound comes from running the output devices at a moderately high bias (not Pure Class A). The heatsinks will be warm to the touch, but if they are too enclosed, the transistors will not dissipate the necessary heat.

Thanks for your input.

Dan

modwright · « **Reply #51 on:** 19 Apr 2019, 04:23 pm »

As far as flimsy or structural integrity, based on the exposed heatsink windows on the side, the base chassis will be heavy gauge steel and the monolithic heatsinks are firmly anchored to the base chassis and the cover, top and bottom. The cover will likely be AL for both aesthetics and further heat dissipation, but the steel chassis is where the structural integrity of the entire unit comes into play.

jtwrace · « **Reply #52 on:** 19 Apr 2019, 04:40 pm »

Quote from: modwright on 19 Apr 2019, 04:21 pm

First of all, twisted pair wires. This is always done when power or signal wires are used, to prevent noise. Power/ground twisted pairs and signal/ground twisted pairs is an effective and ideal way of shielding and noise suppression.

Dan

Why are the transformer wires not twisted then?

modwright · « **Reply #53 on:** 19 Apr 2019, 04:42 pm »

They are not alternating ground and voltage. No advantage to twisting wires of the same or similar voltage. A power or signal/ground twisted pair is a shield. A twisted pair of two voltage conductors is not a shield.

modwright · « **Reply #54 on:** 23 Apr 2019, 06:39 pm »

OK Guys, kicking this product up a notch!

First of all, the cover will be formed AL, not steel as in the proto.
Secondly, I believe the faceplate will be 1/2" and styled like the KWA 150SE.

The footers on our other integrated have been pretty simple. I am thinking of custom footers for this amp, from machined AL, basically large cylinders, in scale with the knobs. What do you guys think would look and perform best?

Specifically, dull spike interface withe shelf?
hemispherical 'bumps' (perhaps 3) to minimize surface contact?
Perhaps a rubber or elastomeric interface between the footer and the shelf?

I know there is much debate between hard and soft isolation, rigid spike or elastomeric absorption. I believe that the ideal would to minimize surface contact if rigid, or use a soft/rubber type interface between the foot and the shelf. Similar isolation will be done at the interface of the footer and the amp. Form will follow function in this case!

Interested in your feedback and input!

Thanks,

Dan

RDavidson · « **Reply #55 on:** 23 Apr 2019, 08:55 pm »

Quote from: modwright on 19 Apr 2019, 04:23 pm

As far as flimsy or structural integrity, based on the exposed heatsink windows on the side, the base chassis will be heavy gauge steel and the monolithic heatsinks are firmly anchored to the base chassis and the cover, top and bottom. The cover will likely be AL for both aesthetics and further heat dissipation, but the steel chassis is where the structural integrity of the entire unit comes into play.

Cool. Sorry, I know "flimsy" was probably a strong word. I think it's the size of the windows vs the rather thin "beams" between the windows that make it appear less solid. I'm sure that structurally it's totally fine. It's a perceptual thing. Please note I'm an industrial designer and design engineer (hybrid?) and am probably more analytical about these visual details than most. What if you made a geometric pattern of squarish M's and W's on the sides for ventilation. Make it appear to be just a pattern like wallpaper, but on closer inspection one can see it's actually M's and W's. Just an idea not necessarily a recommendation. I'd actually have to lay this out to see how it'd look.

I'd also maybe chamfer the edges of the top windows. It'll dress them up a bit and it'll reduce feeling the sharpness of those edges when handling or cleaning.

modwright · « **Reply #56 on:** 23 Apr 2019, 09:15 pm »

I appreciate your input as a designer and design engineer. The goal is to maximize cooling for the heatsinks. That is why they are just short of fully exposed. Having them be blue is a BIG plus aesthetically and at Axpona, everyone said it was DEAD SEXY that way!

Now I am looking at improving the faceplate, engraving vs. silkscreen for the main lettering.
I am also looking at some custom AL footers.

The last issue is the exposed tubes. There are two schools of thought here and I just had a conversation with an old friend about it. He too felt that the tubes being not exposed would make the amp look cleaner. If I do this, there will of course be an access panel with one or two thumb screws, on the back, that will allow for easy access to the tubes. It become a matter of featuring the tubes or not.

Thanks,

Dan

RDavidson · « **Reply #57 on:** 23 Apr 2019, 10:11 pm »

No prob, Dan. Not trying to assert expertise, just POV. I'm certain the pics don't truly do it justice. The blue heatsinks are very "cool."

Agree. I think not having the tubes stand above the case would be a good thing as long as they're still easy to access. Sounds like you have a simple solution to that. I'd still make them visible through the removable door or still visible through the top. Everyone likes seeing that their tubes are glowing, even if through some vent slots or a window. I'm sure you're thinking the same thing.

Maybe IsoAcoustics could make a semi-custom footer solution for you, like the series of speaker footers they make?

cheech · « **Reply #58 on:** 24 Apr 2019, 12:31 am »

Dan, since you asked , my vote would be for not having the tubes exposed on top I think it detracts from the look. Whether you create an access panel, or require the entire case to be removed al la the LS100 (yes more screws but unless someone is constantly rolling tubes no be deal in my mind) would be preferable to me .

Regarding the footers , I have no real preference as I sit all of my amps on either Daedalus DIDs, or Iso Pods

modwright · « **Reply #59 on:** 24 Apr 2019, 07:22 pm »

Thank you both. I am leaning towards having the tubes not exposed but visible via the access panel. I am working on custom footers too.

I appreciate any and all feedback, even if I disagree! I am building this for our customers and we all like different things. Form does follow function and a great sounding and performing product should also LOOK great!

Thank you,

Dan