Hi Chrisb,
As per poseidonsvoice, it is for making more room inside the chassis. I'm trying dual SMPS in the build and if for some odd reasons I don't like it with SMPS, I'll have plenty of room for big old dual toroids and PSUs.
The Sagwee LT v3 are a design from someone I know. It is a 3 way bass reflex design. It was a two years project for the designer but only a limited people build the speakers. You can find the author here, as well as contact him:
Sagwee LT V3: enceinte 3 voies (SC + SB)
The speakers in the thread are not mine but same model. I also have the Troels ATS-4. The amp will travel the two listening areas.
Here's my Troel's ATS-4 thread on the same forum. My friend and I build two pairs.
Troels Gravesen ATS-4!
Hi poseidonsvoice,
Thanks for the compliment! Tom sent me a fully assembled demo unit of the 686 a couple months ago and I really liked the sound of it and thus decided to go on with a 686 build. He's also a very nice guy and quick to answer questions.
I will definitely write my impressions when paired with both the ATS-4 and Sagwee LT v3 once the amp is completed.
Thanks! Yes for saving space and really not hard to do.
Hmmm... Let me think... Bought those ceramic pads a while ago but I believe it could have been eBay or AliExpress...
Something like this:
TO-220/247/264 Alumina Ceramic Insulator Sheets High Temperature Thermal Conduct | eBay
Cool! Do you use SMPS or classic PSU?
Hey would you mind sharing close ups on the LM chips from top, side and bottom? I’d love to see how the legs are bent. Really interested in this approach, but I thought it was not possible (by 3mm or so). Thank you so much
pinnocchio - thanks for the link, but I'm ashamed to be one of those Anglo only west coasters, and couldn't find a link to translate for designer's contact. But, that's OK - I was just a bit curious about the design.
FWIW I heard what I think was Tom's original prototype of the 686 - built with dual SMPS- this August. It drove at least 4 different speakers of my own construction from several single driver full-range systems to a large MTM 2 way, with more power than they need, and certainly authority than any amp I've used on them. My only "complaint" would be that it would be what might be my budget should I be in the market for such a beast.
FWIW I heard what I think was Tom's original prototype of the 686 - built with dual SMPS- this August. It drove at least 4 different speakers of my own construction from several single driver full-range systems to a large MTM 2 way, with more power than they need, and certainly authority than any amp I've used on them. My only "complaint" would be that it would be what might be my budget should I be in the market for such a beast.
I am using classic PSU, but if it was today I would go with two SMPS300RE@-/+30V (one per channel). With that I could use much more smaller case. Amp would be bit underpowered, but I do not that much power anyway.
The SMPS300RE is definitely underpowered, especially if you plan to drive a 4 Ω load. The SMPS500R would be better suited. I don't recall if it comes in ±30 V, but you can have Connex make a custom ±30 V version for an additional $8 if it isn't listed as a standard voltage.
That said, I should also mention that while I used to recommend the Connex supplies, I've grown to be considerably less enthusiastic about them following a recent bulk order with them. The quality of some of the components is hit-and-miss depending on which batch you get. I was fortunate that my bulk order came from a good batch. My initial order of two SMPS300RE arrived with rather cheap mains inlet connectors which I crushed just by turning the screws. I was prepared to have to replace the connectors on all the ones in my bulk order, but thankfully they came from a different batch. I've also had one SMPS300RE (ordered years ago) that needed rework as one of the quick connect terminals pulled out of the board. Neither of these things are show stoppers, they're just not quite production quality.
In addition, Connex's customer service has always been a bit lacklustre and appears to have taken a turn for the worse. For example, I ordered my supplies configured for 120 V mains. They arrived configured for 230 V mains. This is likely due to a misunderstanding as I had asked if this was possible to do on my initial order of two supplies. I clearly specified that I wanted the supplies in the bulk order configured for 120 V. So I now have to spend a couple of hours soldering in wire staples. Again, not a show stopper but just not a production flow. I could also swear they committed to a two-week lead time, yet spent nearly two months building my order with several promises of "shipment this week" along the way. I'm not asking for much. All I expect is that people follow through on their commitments. That's all.
That said, they were able to deliver the supplies in a 100x100x25 mm form factor, which I have not found elsewhere, so that's good.
Tom
That said, I should also mention that while I used to recommend the Connex supplies, I've grown to be considerably less enthusiastic about them following a recent bulk order with them. The quality of some of the components is hit-and-miss depending on which batch you get. I was fortunate that my bulk order came from a good batch. My initial order of two SMPS300RE arrived with rather cheap mains inlet connectors which I crushed just by turning the screws. I was prepared to have to replace the connectors on all the ones in my bulk order, but thankfully they came from a different batch. I've also had one SMPS300RE (ordered years ago) that needed rework as one of the quick connect terminals pulled out of the board. Neither of these things are show stoppers, they're just not quite production quality.
In addition, Connex's customer service has always been a bit lacklustre and appears to have taken a turn for the worse. For example, I ordered my supplies configured for 120 V mains. They arrived configured for 230 V mains. This is likely due to a misunderstanding as I had asked if this was possible to do on my initial order of two supplies. I clearly specified that I wanted the supplies in the bulk order configured for 120 V. So I now have to spend a couple of hours soldering in wire staples. Again, not a show stopper but just not a production flow. I could also swear they committed to a two-week lead time, yet spent nearly two months building my order with several promises of "shipment this week" along the way. I'm not asking for much. All I expect is that people follow through on their commitments. That's all.
That said, they were able to deliver the supplies in a 100x100x25 mm form factor, which I have not found elsewhere, so that's good.
Tom
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Indeed if you predicate the over all compact form factor, and order bespoke components from other suppliers for a kit such as the Mod286 based on the specified performance and dimensions of a major component such as this, it could certainly add to your - to quote Barak Obama - "rhymes with bucket list"
If I was more business minded than engineering minded, I would have performed an external analysis of the Modulus-286 Kit project and concluded that hinging the project on a single vendor was a really bad idea. Then again, it's one thing to read that in a textbook and quite another to realize that if this single point fails, I'm flushing a $10k+ investment down the drain. Thankfully it worked out well this once, but it's certainly more risk than I'm comfortable with.
Tom
Tom
True, but almost by definition every new product development I've been involved with has multiple single-point failures due to single-sourced components or assemblies. All the more true if the project isn't 'jelly bean'. However, when you are buying a subassembly, such as the Connex power supply, you would hope that the vendor is building in a consistent fashion from a consistent bill of materials (BOM). If you are a big company, you have a team of people involved in both the engineering and business side of 'vendor management'. If you're Tom, you don't have the resources to throw at this task.
Me too. I'd greatly appreciate Do's review should he find time to write.
Thanks,
Tom
Let’s get back to the wonderful engineering that Tom is able to put into his entire and evolving product offerings, and the performance derived there from. With sufficient market acceptance, this should be both a data point in strategic project management and a fondly remembered minor hiccup- there will be more, no doubt- in a long and successful business career.
Well, yeah. #perspective. I'm not kicking myself over this. It's just been one of those learning experiences of "wow, that could have been really bad. But it worked out alright, so I'm moving on as a wiser person".
Some things (like having to swap a few connectors) are perfectly acceptable in the DIY world. The same things may not be acceptable once you have to ship, say, 100 kits/year and charge a premium for a good product. I'd rather under-promise and over-deliver than the opposite and need vendors who can support me in this. That's all.
Tom
Some things (like having to swap a few connectors) are perfectly acceptable in the DIY world. The same things may not be acceptable once you have to ship, say, 100 kits/year and charge a premium for a good product. I'd rather under-promise and over-deliver than the opposite and need vendors who can support me in this. That's all.
Tom
Here's some pics you requested. Hope they're useful for those who wants to install it this way. I used a drill bit parallel to the chip to do the round bend of the second row.
I will definitely write about it when all done and several hours of burn in.
Thanks
Do
Thank you sooooo much for the pics, Do! Really helpful.
That's a really good business (and life) resolution indeed, and it really shows in your daily messages as well. One can easily tell the passion you put into it by the way you interact with your clients (or leads), all of which gives a great peace of mind to the casual, untrained builder.
That's a pretty neat trick. One could entertain the thought of doing the same for the first row of leads to get the bend a little further away from the IC package. There isn't a whole lot of lead length to work with, though.
Thank you. I appreciate it.
Tom
That is great! I wish Tom also offered mod-286 and mod-186 without LM3886 soldered, so that anyone could do the same trick on those ... saves a lot of space and brings a lot of fun
That is great! I wish Tom also offered mod-286 and mod-186 without LM3886 soldered, so that anyone could do the same trick on those ... saves a lot of space and brings a lot of fun
Unfortunately, offering the SMD-only boards also increases cost for everybody and drives up the number of support emails. I do enjoy providing support, but it takes me away from growing my business, so I have to do what I can to limit the number of support calls. Also, when someone spends good money on a partially assembled board, they need the rest of the build to come together smoothly. The fully assembled modules facilitates this, thus, help me continue my business.
Tom
I totaly got your point Tom and fully support your business strategy. I would actually did the same. It is just a wish