Yes, from a thermal standpoint the centre would be the best. My thoughts however would be to keep my PSU away from the amplifier modules as much as is reasonable to avoid inducing any unwanted SMPS 'hash' into the amplifier.
Need to give it some thought.
I have always used the pre-out off my main system to feed my amplifiers, so the added control would be redundant, for me at least. I could see in a small dedicated set-up that might be useful. You got some of those cheap-n-cheery DACT type knock-off stepped attenuators from eBay. Are you happy with those?
With no control in there I gain the benefit of really short input wiring
.
That should be fine. It will just change the corner frequency of the input filter slightly downward. You could replace the filters R (the 1K6) to a lower value to keep the filter tuned the same but it shouldn't make any meaningful difference.
Jason,
Which SMPS are you using in the amp photo above please? (I have a pair of those Hypex 400s recommended by LC for his first version)
I hope soon to be getting on with mine now that I have been given the OK after surgery. I also hope soon to have LC's full kit for his latest version. And I am also going to build LC's first GP VSSA……so I will have a few versions for comparison over here in Scotland.
Which SMPS are you using in the amp photo above please? (I have a pair of those Hypex 400s recommended by LC for his first version)
I hope soon to be getting on with mine now that I have been given the OK after surgery. I also hope soon to have LC's full kit for his latest version. And I am also going to build LC's first GP VSSA……so I will have a few versions for comparison over here in Scotland.
Last edited:
That is one of the Connexelectronic SMPS500R power supplies, 120V input, +/-45V output with ~+/-12V auxiliary output.
Sounds interesting, post some pics when things get underway.
I went for the 45V output only because that is the practical limit and for a real build I wanted to maximize output. I sincerely doubt there would be a sonic difference between 38V supplies and 45V. I hope to make some headway this weekend getting things mounted so I can give it a listen. I'm still waiting for input and output connectors to arrive.
Terry,
i had a pair of the Connex 500r +-45V hooked up to LC's Orig. VSSA. In my opinion, after blowing things up & going with a traffo & CM board the biggest & only diff i noticed right away was OOMPH. I have very inefficient Spkrs and i think the extra drive helps with that at higher volume.
I have ordered another 500r for This VSSA, so i will have another comparison ( if my memory holds up! ).
Rick
Royber,
Somewhere along the line I did state that the 2SK1056 was a typo, we want the 2SK1058. They are the same device with different voltage ratings. C3 can be anything that is convenient, just bend the leads to fit the location. Most of the small capacitors suited to the C3 location will be less than 5mm LS.
You can use the Rev 'C' Mouser BOM for Rev 'B' boards, there were no major changes. I just pushed the power spades and caps around but did not alter any component dimensions.
Hope that helps clarify things.
What would you guys suggest as the best transformer option from Mouser for this amplifier build? I started here http://www.mouser.com/ds/2/177/5c0024-25-81175.pdf and found the 182G18.
I'd suggest shopping for an decent SMPS. You will have the whole PSU for about the same price as the transformer alone.
Something like this, or the +/- 45V version (that's the max for these boards)
Something like this, or the +/- 45V version (that's the max for these boards)
Thank you. I am leaning more towards a SMPS. Where else are folks by trafos from?
i have bought 2 trafos form these people, & i Like them a lot. Much smaller than Antek, although the price With shipping from Canada is kind of high. Email them what you want & they will Quote you a price which includes shipping.
Transformer Designs | Primrose Audio
Transformer Designs | Primrose Audio
Jason thanks for the Mouser Bom..
As I gather all the parts (still waiting on some others)
I have been reading the installation manual the was posted earlier, and have read the forum as well.
Since this is my first build (a real newbie) those manuals have confuse me more than help me. It looks like the manual is for an earlier card.
You have some photos on post #48 the might be easier to follow for a newbie than manuals.
Can you or someone else can post better pictures and newer instructions for some of us to follow.
Any help will be greatly appreciated.
Thanks to all
Cesar
As I gather all the parts (still waiting on some others)
I have been reading the installation manual the was posted earlier, and have read the forum as well.
Since this is my first build (a real newbie) those manuals have confuse me more than help me. It looks like the manual is for an earlier card.
You have some photos on post #48 the might be easier to follow for a newbie than manuals.
Can you or someone else can post better pictures and newer instructions for some of us to follow.
Any help will be greatly appreciated.
Thanks to all
Cesar
Hi Cesar,
I began to make a post about general assembly but it was getting long. What I will do is type it out and post a text file / PDF as a 'guide'. It won't be anything fancy. I'm going to be real explicit, so please don't feel insulted if I state something obvious to you. I'd rather say it than assume anything.
I doubt you will have any real issues, the silk screen on the board will tell you what needs to be on the board and where. If it isn't clear then here's a few little tips:
Resistors, designated by an R#, are all 1/4W except R20 and R21, which are 1W. The value is in the box representative of the devices body. They are read like this - 10R=10Ω, 100R=100Ω, 10K=10kΩ, 2K2=2.2kΩ, and so on.
Capacitors are designated by a C#. They are either directly marked with their capacity such as values of 1µF and above, or use industry standard IEC markings like 220=22pF, 471=470pF, 473=47nF and so on. Polarity of the electrolytics is marked with a '+' on the positive terminal and a filled area to denote the stripe usually on the body of the device marking the negative side.
Semiconductors are labeled by type and the shape should clearly indicate the orientation. For the diodes the stripe on the silk needs to match the stripe on the device. For the heat sink mounted devices the text printed on the device faces up, away from the heat sink. use appropriate insulators during the pre-assembly step so things line up properly when final assembly time comes.
The two spacers / stand-offs on the input side of the board are best to be 5mm (or sometimes 5.2mm) long to match the thickness of the MOSFETs. When fitting the MOSFETs and VAS devices pre-drill the heat sink and tap the holes so you have a solid fixture to position the parts during soldering.
The trimmers VR1 and VR3 are best pre-set to the middle (new from factory are usually delivered centred, just verify that) and VR2 set for maximum resistance in-circuit. For the specified type that is fully clockwise.
That should get you started. If you (or anyone else for that matter) have specific questions please ask, I will help as much as I can. My best advice is work slow and careful, don't get impatient. If something isn't clear ask me for clarification. The bonus here is they aren't complicated and should go together pretty easy.
I began to make a post about general assembly but it was getting long. What I will do is type it out and post a text file / PDF as a 'guide'. It won't be anything fancy. I'm going to be real explicit, so please don't feel insulted if I state something obvious to you. I'd rather say it than assume anything.
I doubt you will have any real issues, the silk screen on the board will tell you what needs to be on the board and where. If it isn't clear then here's a few little tips:
Resistors, designated by an R#, are all 1/4W except R20 and R21, which are 1W. The value is in the box representative of the devices body. They are read like this - 10R=10Ω, 100R=100Ω, 10K=10kΩ, 2K2=2.2kΩ, and so on.
Capacitors are designated by a C#. They are either directly marked with their capacity such as values of 1µF and above, or use industry standard IEC markings like 220=22pF, 471=470pF, 473=47nF and so on. Polarity of the electrolytics is marked with a '+' on the positive terminal and a filled area to denote the stripe usually on the body of the device marking the negative side.
Semiconductors are labeled by type and the shape should clearly indicate the orientation. For the diodes the stripe on the silk needs to match the stripe on the device. For the heat sink mounted devices the text printed on the device faces up, away from the heat sink. use appropriate insulators during the pre-assembly step so things line up properly when final assembly time comes.
The two spacers / stand-offs on the input side of the board are best to be 5mm (or sometimes 5.2mm) long to match the thickness of the MOSFETs. When fitting the MOSFETs and VAS devices pre-drill the heat sink and tap the holes so you have a solid fixture to position the parts during soldering.
The trimmers VR1 and VR3 are best pre-set to the middle (new from factory are usually delivered centred, just verify that) and VR2 set for maximum resistance in-circuit. For the specified type that is fully clockwise.
That should get you started. If you (or anyone else for that matter) have specific questions please ask, I will help as much as I can. My best advice is work slow and careful, don't get impatient. If something isn't clear ask me for clarification. The bonus here is they aren't complicated and should go together pretty easy.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.