Amp layout?

whoaru99

Epic Member
Getting closer on the KT88 PSE ULs...

The cardboard is 17 x 10.

Pardon the salt and pepper "capacitors", but they are similar in diameter and height to what I have in mind.

Looks like lots of dead space up top (there will be more decently large capacitors, and of course other stuff underneath).

How much does one try to squeeze all this stuff together?

20171027_234958.jpg
 
Looks good, that's what I would layout. Wires are smooth from driver to power tubes to OT. Everything away from the power transformer. Good!!!:thumbsup:

I would not try to squeeze the power supply too close to the OT. I had problem with my kit amp power transformer induce hum into the output transformer. I verified it is the case because I can use the thick aluminum plate and stick it between the two transformer on the other side and lower the hum. Nothing else works, it's core to core. You have better luck as you wisely choose the torroidal powr transformer already. If it is not for you mentioned about Amtek has HV transformer, I would never know about it. I did not realize they have HV transformer from 400VA or less. I always looking at 500VA and up and never knew they make HV transformer. Now I know.

What are the two salt shaker like thing? Big caps?
 
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This is getting picky, I would move the salt shaker that goes to the CT of OT closer to the OT. But it's not that critical. I like the caps in between the OT and PT, this help a little in blocking any leakage magnetic field from the transformer from talking to each other.

that location is the same location I put a thick aluminum panel and observe reduction of 120Hz interference to the output.
 
The salt and pepper 'caps' are a fun shape. No reason why restuffed caps couldn't be put into other shapes, like models of the Empire State Building, Eiffel Tower, bronzed baseball, etc.
 
Nice layout Who,and there is much to recommend your straight line audio configuration. As you've said though,it does leave some open area right in the middle of the map.

I have always made it a point with my designs to breadboard my (potential) transformer mechanical layout,then energize the power transformer (preferably as close to under load as possible) and measure the interactions with other transformers and inductors.This practice may have more relevance with non-toroidal power transformers,but it couldn't hurt to try.This has usually been the determining factor in just how much I can ''squeeze down'' my layout.The nice thing about toroidal power transformers is their very minimal leakage flux which limits electromagnetic interference.

I don't know your circuit details,but I might consider going to an ''inline'' (left to right) tube layout that would place the miniature type in that middle portion,but this destroys that beautiful circuit symmetry. Perhaps,instead,a bias control with a nice mechanical meter movement to fill things in?

Whenever I consider monoblocks I'm always torn between the two usual configurations; Wide x Shallow VS Narrow x Deep. Both have their merits,and the decision is difficult.

Wide x Shallow: Lots of visual cues and a generally more impressive,substantial appearance. Also, easier and more conventional in layout,both mechanical and electrical.
Drawback is finding the real estate for placement,depending on your room and setup,and getting them close to speakers to reduce speaker cable length.

Narrow x Deep: Not a lot to look at,especially from the front. Appearance is more of a commercial or industrial nature,so not to everybody's taste. They only look good if
they are on the floor and you are looking down at them.Mechanical layout is tighter,and electrical requires a higher degree of consideration and finess in order to prevent circuit interaction.Assembly is also more difficult due to the compact nature.But,the bonus (and some will argue the only merit) of this configuration is the ease of placement,whether in a rack or on the floor directly beside the speaker.

Cheers,

Art
 
Am going to stick with cathode bias at present.

I could fill a lot of that area if I didn't hide the three stacked film caps underneath. Each of those three caps is 58mm L x 35mm W x 50mm H. So the lot of them would take up some real estate.

However, I'm not seeing a clear way to cleanly mount them on top that also looks half decent. Any ideas?
 
Let's keep this thread on track folks!
Regards,
Jim
 
Mod... How about replacing those posts back in. I was dead "serious," about design ideas he asked about. I was giving some out of the box thought that no one on these boards ever seems to consider. I didn't say anything inappropriate, just a bit of humor, with visuals.

I asked for them to be removed. Once was fun, the trend was not.
 
What is that silver transformer in the front of the toroid? A choke or maybe a filament supply? If it's a filament supply, I'd leave it just as is. If it's a choke, you could cut the width down to say 16" or even 15". Nice thing about toroids is they keep the EM field confined nicely.
 
I knid of like the meter idea. The round ones I see a lot aren't very deep. Maybe room for an aux input too. A quick plug in for a smart phone, ect.
 
What is that silver transformer in the front of the toroid? A choke or maybe a filament supply? If it's a filament supply, I'd leave it just as is. If it's a choke, you could cut the width down to say 16" or even 15". Nice thing about toroids is they keep the EM field confined nicely.

It's a choke. Unfortunately I don't know the exact specs. Based on weight and DC resistance it parallels others of 2 - 2.5H and 200 - 300mA.
 
Nice layout Who,and there is much to recommend your straight line audio configuration. As you've said though,it does leave some open area right in the middle of the map.

I have always made it a point with my designs to breadboard my (potential) transformer mechanical layout,then energize the power transformer (preferably as close to under load as possible) and measure the interactions with other transformers and inductors.This practice may have more relevance with non-toroidal power transformers,but it couldn't hurt to try.This has usually been the determining factor in just how much I can ''squeeze down'' my layout.The nice thing about toroidal power transformers is their very minimal leakage flux which limits electromagnetic interference.

.......................
Cheers,

Art
Good point. I'll do that. :thumbsup:, Particular I want to design a stereo amp, it's going to be more packed.

I definitely going to get the torroidal power transformer. I am still debating about the output transformer whether to go torroid or IE.
 
Getting closer on the KT88 PSE ULs...

The cardboard is 17 x 10.

Pardon the salt and pepper "capacitors", but they are similar in diameter and height to what I have in mind.

Looks like lots of dead space up top (there will be more decently large capacitors, and of course other stuff underneath).

How much does one try to squeeze all this stuff together?

View attachment 1033555

Hey Whoaru99
What are those black socket like thing under the power tubes? Are those real socket you put onto the chassis? Can you tell me where you get those?

Alan
 
Hey Whoaru99
What are those black socket like thing under the power tubes? Are those real socket you put onto the chassis? Can you tell me where you get those?

Alan

They kind of look like relay sockets... that’s going to be my guess
 
No need to pack parts closer together than necessary. Keeping the power as far from the signal as practical is a good idea too. Just for cosmetics though I would probably make the centerline of the choke line up with the centerline of the toroid. A bias meter or test points in the dead space between the choke (i assume its a choke anyway) and the driver tube can help eat the space. You can also just find a cool logo to put in that spot.

I also tend to favor the "diamond" layout of output tubes behind and to either side of the driver with the output transformer centered behind the output tubes. it seems to nicely facilitate component fitment. I've got stuff laid out in other ways and most of them are just overly messy underneath as a result. It also lets the component placement and lead lengths be close to identical.
 
I am still debating about the output transformer whether to go torroid or IE.

I would avoid the toroidal output transformers. Despite all of the published ''papers'' and performance claims,and after much experimentation within my group of cronies,we decided that these alleged performance claims were non existant in the real world.In addition,any DC imbalance whatsoever has serious effects on behaviour.
 
Hey Whoaru99
What are those black socket like thing under the power tubes? Are those real socket you put onto the chassis? Can you tell me where you get those?

Alan

They kind of look like relay sockets... that’s going to be my guess

They are indeed octal relay sockets. Those will not be used in the build, but they worked nicely for holding the tubes.

My thought for the actual mounting is along the lines of the vented plates. http://www.angela.com/index.aspx/ImageGallery/Index?productId=4723
 
I would avoid the toroidal output transformers. Despite all of the published ''papers'' and performance claims,and after much experimentation within my group of cronies,we decided that these alleged performance claims were non existant in the real world.In addition,any DC imbalance whatsoever has serious effects on behaviour.
Yeh, I read an article that said even though the IE transformer has more distortion at low frequency, but the base actually sounds better and stronger than torriodal transformer.
 
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