When I turned it on, I heard a pop and saw sparks. It seems like I blew DR1 and DR2. Any theories for what happened? Can it be saved?
...
Do you think the heatsink could have caused DR1 and DR2 to blow on the first channel?
Sorry for your problem...
I suggest you to post the question to this more specific thread:
http://www.diyaudio.com/forums/chip-amps/167458-myrefc-build-guide.html
BTW
Is your LM3386 the TF insulated or the T uninsulated?
If it's the T version:
- did you use the insulator and washer between the LM3886 and the heatsink?
- Is your heatsink 'floating' or is it grounded?
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Thanks for the reply.
Its the insulated version. The other channel just blew. DR3 and DR4 this time
It happened right when I plug the power cord in. (I didn't use a power switch.)
I will make a post in the other thread as you suggest.
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Which BOM are you using?
The simpler a design is, the more components are going to be critical on performance with the power supply considered as part of the circuit down to the transformer. I have no doubt that the F5 will need the exact components to get the exact performance.
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OK Uriah - you knew it was comming
I want to know too.
Ordered for (4) standard MefRef Kits
I sent the money via PayPal. What is the status of my four standard MyRef
PCB's and kits? I ordered and payed for four (4) MyRef PCB's and standard kits.
but so I have not received my kits. After reading through other group buy threads,
I'm nor sure the group buy system is working very well. If I order from Chinese
sites on eBay, I receive the parts without much trouble. Even if the parts come from across the world. Maybe the Group Buy people are taking on more than they can
deliver. It's a huge job so some patience is required.
I sent the money via PayPal. What is the status of my four standard MyRef
PCB's and kits? I ordered and payed for four (4) MyRef PCB's and standard kits.
but so I have not received my kits. After reading through other group buy threads,
I'm nor sure the group buy system is working very well. If I order from Chinese
sites on eBay, I receive the parts without much trouble. Even if the parts come from across the world. Maybe the Group Buy people are taking on more than they can
deliver. It's a huge job so some patience is required.
Who did you send the money to? Perhaps it would be better to send that person an email rather than post to the board.
If you are talking about Siva/linuxguru, then realize he is shipping from fairly far away and it may take a bit for him to get the package together.
Comparing his kit to the Chinese knock-offs on ebay (not all but many) is an apples and oranges thing - he uses very good components whereas many of the cheap e-bay kits use pretty crappy stuff.
Bingo.
-bill
I'd love to hear your detailed opinion on this too, Uriah.
have you tried the ann modules, btw?
Sent private not to linuxgura
I sent the money to linuxgura. I sent him a private message stating that my concern was
caused by being new to diyAudio.com and Group Buys. After reading about the
BlueFusion's Objective2 and Johener's Objective2 Group Buys, is it any wonder
that a newbie could get concerned about Group Buys in general . This type of Group Buys could kill the Group Buy system.
I have purchased many items from Chinese vendors. So far I have not seen any problems with the items I've purchased. Yes, there might be problems and bad vendors, but so far I have not seen these problems.
I sent the money to linuxgura. I sent him a private message stating that my concern was
caused by being new to diyAudio.com and Group Buys. After reading about the
BlueFusion's Objective2 and Johener's Objective2 Group Buys, is it any wonder
that a newbie could get concerned about Group Buys in general . This type of Group Buys could kill the Group Buy system.
I have purchased many items from Chinese vendors. So far I have not seen any problems with the items I've purchased. Yes, there might be problems and bad vendors, but so far I have not seen these problems.
I cant get into the differences as the side by side comparison was over 3 years ago. Difference was not subtle though with F5 a clear winner, but why would we be assuming that a class AB chip should beat the F5? I built and now listen to a Chip and am quite happy but I never intended to build an F5 killer and surely didnt.
I can support Uriah's views. While I haven't yet built an F5 (speaker projects taking up all my time), I do have a Papa-built FW amp (thanks Papa) that simply blows away the MyRefC in every department. Soundstaging, sweetness, roundess, transients, detail retrival, and that superb sense of musical flow. Then again, you didn't expect an LM3886 to compete with a properly designed Class A amp, did you?
Let's try to put this amp comparison in perspective, shall we? I have not heard an F5, but I'm sure it is a superb amplifier. Nelson Pass is rightfully regarded as the guru of DIY amplifiers, among other things. His designs are elegant and sonically sublime, but I think that sometimes his reputation inflates the perception of them. I did own a Threshold 400A way back when they were new (late 70's, before most people knew who Nelson Pass was), and I can tell you it was among the better amplifiers available at any price. It had a somewhat clinical sound, but absolutely pure and controlled, very powerful for its wattage.
Which brings us to the F5. It is rated at 25 watts, and consumes 180 watts at idle. It has low gain, though can safely drive very difficult loads. Compare that to the MyRef, which can ideally provide 60+ watts, yet is very efficient. I run mine all day long and it never gets the modest heatsink as much as warm. The F5 has massive heatsinks and typically reaches 50C or so without cause for alarm. In fact, it won't even play properly for the first hour until it gets hot!
The MyRef is very simple and easy to construct, despite the problems documented here by people who are clearly incompetent or possibly unlucky. It should require no maintenance or adjustments for years. It is stable under most conditions and is resistant to modest abuse. It's as close to plug-n-play as DIY gets. The F5 is somewhat complex, requiring sensitive adjustments by the builder to achieve proper performance.
I'm sure the F5 sounds better, and it should. It costs more, uses ten times more energy, and is considerably more difficult to build and operate. If the proper components are used for construction and in a system that suits its strengths, I bet the MyRef and F5 are closer in performance than described here. In fact, I would bet the MyRef is close in performance to many amps that cost five to ten times as much. Not better in a side-by-side comparison, but close enough that perhaps you wouldn't remember the difference.
Peace,
Tom E
Which brings us to the F5. It is rated at 25 watts, and consumes 180 watts at idle. It has low gain, though can safely drive very difficult loads. Compare that to the MyRef, which can ideally provide 60+ watts, yet is very efficient. I run mine all day long and it never gets the modest heatsink as much as warm. The F5 has massive heatsinks and typically reaches 50C or so without cause for alarm. In fact, it won't even play properly for the first hour until it gets hot!
The MyRef is very simple and easy to construct, despite the problems documented here by people who are clearly incompetent or possibly unlucky. It should require no maintenance or adjustments for years. It is stable under most conditions and is resistant to modest abuse. It's as close to plug-n-play as DIY gets. The F5 is somewhat complex, requiring sensitive adjustments by the builder to achieve proper performance.
I'm sure the F5 sounds better, and it should. It costs more, uses ten times more energy, and is considerably more difficult to build and operate. If the proper components are used for construction and in a system that suits its strengths, I bet the MyRef and F5 are closer in performance than described here. In fact, I would bet the MyRef is close in performance to many amps that cost five to ten times as much. Not better in a side-by-side comparison, but close enough that perhaps you wouldn't remember the difference.
Peace,
Tom E
I completely agree with Madisonears. You build the two different amps for two different reasons. Why didnt I build an F5 yet? Well because its expensive, its huge, its heavy, I cant find a case I can afford to put it in and dont want to build one.
The MYREF rocks. Sounds, like Tom said, incredible and competes with and beats many multithousand dollar amps. You can break it and your expenses are low to fix it. You have a huge thread of dedicated guys working to improve every last note in the amp.
Both are great amps. Look what a great job Bob is doing on his MyRef integrated! Its his first serious build and so far smooth sailing plus he's learning a lot and when he is done he will have a wonderful amp to listen to for years and years.
There's lots of threads about the 'best' amp out there. 'Best' is defined by your needs and limitations. So define those before you try to find your next project.
The MYREF rocks. Sounds, like Tom said, incredible and competes with and beats many multithousand dollar amps. You can break it and your expenses are low to fix it. You have a huge thread of dedicated guys working to improve every last note in the amp.
Both are great amps. Look what a great job Bob is doing on his MyRef integrated! Its his first serious build and so far smooth sailing plus he's learning a lot and when he is done he will have a wonderful amp to listen to for years and years.
There's lots of threads about the 'best' amp out there. 'Best' is defined by your needs and limitations. So define those before you try to find your next project.