The Duetta (Duet mod)

art · « **Reply #40 on:** 7 Mar 2009, 01:24 am »

OK, two things:

I should be ready to start taking orders in a few weeks. Going ahead with my gut feeling, in lieu of complete feedback. A bad confluence of timing on this subject.

The main point is digital mod only.

The reasons for this are twofold.

First, I want to keep the cost down as low as possible. Regardless of how good it sounds stock, and how much I can improve it, it is only a $150 or so unit. I can not see spending a ton of money making it better. As "mission creep" worked its way in, it was looking like it might be worthwhile to look for a second-hand Transporter. So, the only way to assure it would be affordable was to define the level of upgrade that had the broadest appeal.

And speaking of cost.............

The analog mod turned out to be a major pain to do. The added time to do this was going to run the price too high.

So, bottom line was there are only 2 ways to keep costs low: parts or labour. Parts meant sacrifice in either performance or features. Performance will not be cut, as doing so would negate the purpose. Cutting features did not affect the parts cost much. But cutting features keeps the time spent working on one down to a workable amount of time.

Hate to disappoint many of you, but in all honesty, trying to find a practical way to mod the analog section is largely responsible for the delay.

Some other good news:

The clock has been improved slightly. Came up with a few things that may not affect performance greatly, but are nicer touches.

Pat

tubesguy2 · « **Reply #41 on:** 8 Mar 2009, 09:10 pm »

Hmm -

I'm 58, but only read at a 44 year-old level, so I'm a little confused. Your post seems to indicate that the analog mod is a pain, too expensive, etc, but you preface that with "analog mod only" and so I'm wondering.

At any rate, whatever the mod is, looking forward to hearing final price and a final features list. Sounds like you're feeling a bit better, too, and so you got that goin' for ya. - Pat

art · « **Reply #42 on:** 8 Mar 2009, 10:35 pm »

Call it lack of sleep. Glad someone is awake, and proofreading it. Thanks. (I fixed it.)

Pat

tonyptony · « **Reply #43 on:** 9 Mar 2009, 10:56 pm »

Quote from: art on 7 Mar 2009, 01:24 am

OK, two things:

I should be ready to start taking orders in a few weeks. Going ahead with my gut feeling, in lieu of complete feedback. A bad confluence of timing on this subject.

The main point is digital mod only.

Pat, that's okay by me, I guess, since that's how I operate my SB3 right now anyway. But if I may I would like to comment on a lack of feedback from the guinea pigs out there. If there's a reason for it that's okay, too, but with no offense at all intended I would have liked to have seen a bit more in the way of testers' experience and evaluation. I do appreciate at least what we got from arthurs.

arthurs · « **Reply #44 on:** 9 Mar 2009, 11:37 pm »

I have the new (maybe final?) power supply and owe Pat some feedback but my schedule has sucked major...I'm going to be home and unencumbered starting this weekend so I'll put some time in and write something more up on the digital output and the new power supply....seems like I'm off the hook on analog...

Sorry Pat, I'm paddling as fast as I can....

art · « **Reply #45 on:** 9 Mar 2009, 11:46 pm »

That makes two of us. I know you are slammed.

(I've been busy with a top-secret project. Proto working now as I write this. Also means I will get back to Duetta soon. Some tricks from it will be ported over to the Duetta. That is why we are called research. Still looking for it, maybe some day we will find it.)

Pat

jhm731 · « **Reply #46 on:** 10 Mar 2009, 01:02 am »

Quote from: tonyptony on 9 Mar 2009, 10:56 pm

Pat, that's okay by me, I guess, since that's how I operate my SB3 right now anyway. But if I may I would like to comment on a lack of feedback from the guinea pigs out there. If there's a reason for it that's okay, too, but with no offense at all intended I would have liked to have seen a bit more in the way of testers' experience and evaluation. I do appreciate at least what we got from arthurs.

The Duetta has been in my system since 11/08.

I've tested three different PSUs and provided feedback to Pat.

I didn't think it was important for me to post which PSU version I kept, since
Pat will decide which one he'll offer.

I tested the analog output when I had an AVA Insight 440H amp here in December, but quickly went back to my
full digital set up.

If Pat will be ready to start taking orders for digital mod only in a few weeks, I suggest you get your Duet ready for shipping.

Aloha,

Dan

Current set-up: Duetta w/U-byte cable->Aberdeen Tact RCS 2.2XP->Aberdeen Tact S2150->Volent VL-2s.

tonyptony · « **Reply #47 on:** 11 Mar 2009, 12:57 am »

Quote from: arthurs on 9 Mar 2009, 11:37 pm

I have the new (maybe final?) power supply and owe Pat some feedback but my schedule has sucked major...I'm going to be home and unencumbered starting this weekend so I'll put some time in and write something more up on the digital output and the new power supply....seems like I'm off the hook on analog...

I do appreciate the update, arthurs. While one could argue the merits of hearing other people's impressions of a device, I would argue that if you've been around long enough and have some experience with a broad range of gear, that there is some value in getting that review.

Quote from: jhm731 on 10 Mar 2009, 01:02 am

I've tested three different PSUs and provided feedback to Pat.

I didn't think it was important for me to post which PSU version I kept, since
Pat will decide which one he'll offer.

Dan, I would respectfully disagree. Your thoughts as to how they stacked up, including the stock supply as a control point, would be useful to me at least. Yes, Pat will make his decision based on feedback and a number of additional factors (producibility, cost, reliability, measured performance, etc, etc). But your info will give us some sense of where we may expect to go with his improvements. I for one would be very happy to read your assessments.

tonyptony · « **Reply #48 on:** 11 Mar 2009, 01:01 am »

Quote from: art on 9 Mar 2009, 11:46 pm

That makes two of us. I know you are slammed.

(I've been busy with a top-secret project. Proto working now as I write this. Also means I will get back to Duetta soon. Some tricks from it will be ported over to the Duetta. That is why we are called research. Still looking for it, maybe some day we will find it.)

Pat

Like I said, Pat. I am a patient guy. aa If this may be an additional improvement for the Duetta in the relative near term then I can wait.

jhm731 · « **Reply #49 on:** 11 Mar 2009, 02:20 am »

Quote from: tonyptony on 11 Mar 2009, 12:57 am

Quote from: jhm731 on 10 Mar 2009, 01:02 am
I've tested three different PSUs and provided feedback to Pat.

I didn't think it was important for me to post which PSU version I kept, since
Pat will decide which one he'll offer.

Dan, I would respectfully disagree. Your thoughts as to how they stacked up, including the stock supply as a control point, would be useful to me at least. Yes, Pat will make his decision based on feedback and a number of additional factors (producibility, cost, reliability, measured performance, etc, etc). But your info will give us some sense of where we may expect to go with his improvements. I for one would be very happy to read your assessments.

Once Pat mods the Duet receiver, the stock supply can no longer be used.

IMO, all of the linear PSU versions sound better than the stock supply....smoother/cleaner SQ.

It's tough to quickly A/B the different PSU versions. I felt V2 and V3 were better than V1. I preferred V3 by a small margin (a slightly more open soundstage) over V2.

Pat says that clock has been improved slightly, and I haven't heard this change, so I don't know if the PSUs still make a difference.

art · « **Reply #50 on:** 11 Mar 2009, 06:00 am »

Looks like the PSU design will ultimately come down to using parts from other projects (that we hope will be products) in order to contain costs. Yes, that means it will be the most expensive version.

Good for you guys.......so-so for our bottom line. Hoping to hold the line @ $500. By making designs have more commonality, we should get enough cost savings to meet our price objective.

As an aside.........trying to fit all of the products, in the same enclosure, with the same supply is getting tricky. One PCB has all the parts touching each other. If I only had 1/4" more to work with.........but I don't.

Pat

tonyptony · « **Reply #51 on:** 5 Apr 2009, 10:55 pm »

Just hanging around...

art · « **Reply #52 on:** 13 Apr 2009, 11:47 pm »

Almost done with income taxes...........should be able to return to generating funds soon, as opposed to shelling it out.

At least I hope so. That is the plan.

Pat

art · « **Reply #53 on:** 4 May 2009, 03:13 am »

More PCBs on order. Some minor refinements, that came about while designing the Legato.

Info on it here, in case anyone cares:

http://www.audiocircle.com/index.php?topic=67762.msg626170#msg626170

Pat

tonyptony · « **Reply #54 on:** 4 May 2009, 01:47 pm »

Hmm, interesting. So you've incorporated some sort of independent asynchronous handler in the Duet conversion to feed the digital out? Also independently powered?

art · « **Reply #55 on:** 4 May 2009, 05:36 pm »

No.....

They just use a lot of the same circuits. Anything gleaned on it is applied to the Duet.

But, it does reclock the output. As it always did.

(Had to get new PCBs partly because the are some mistakes on the layout.)

Pat

tonyptony · « **Reply #56 on:** 4 May 2009, 10:56 pm »

Good stuff. All well thought out improvements welcome.

art · « **Reply #57 on:** 22 May 2009, 01:18 am »

I know some of you are getting impatient, and I don't blame you. I think I finally have a version of the PCB that fits nicely, installs easily, and still has some refinements.

There are several coax cables that have to go between my PCB and the Duet, et al. The way the cables are routed and dressed have a significant impact on how it goes together. It has to go together in both an aesthetically pleasing manner, and a way that doesn't take hours to do.

As mentioned previously, circuit refinements that came out of the Legato development have been added into what will become the final version.

Pat

tonyptony · « **Reply #58 on:** 23 May 2009, 08:23 pm »

Good to hear, Pat. When you're happy with the final design I'd like to get some sense of how it looks empirically.

ajayrav · « **Reply #59 on:** 24 May 2009, 12:36 am »

Quote from: tonyptony on 23 May 2009, 08:23 pm

Good to hear, Pat. When you're happy with the final design I'd like to get some sense of how it looks empirically.

Me too