100W Ultimate Fidelity Amplifier

...so i decided to make a test rig (i hope i wrote it right),a chasy with adjustable power supply, wide heatsink, dc-protect / mute/overload, input/output conectors, carefully insulated primary and grid connections. that way only thing i put my money in will be new design amplifier pcb's - and they actually come cheapest in all this story. it is a way to invest in nice and quality power supply, protection and cooling not more than once,and to equaly enjoj every next project. will dojust that...
 
...so i decided to make a test rig (i hope i wrote it right),a chasy with adjustable power supply, wide heatsink, dc-protect / mute/overload, input/output conectors, carefully insulated primary and grid connections. that way only thing i put my money in will be new design amplifier pcb's - and they actually come cheapest in all this story. it is a way to invest in nice and quality power supply, protection and cooling not more than once,and to equaly enjoj every next project. will dojust that...

Exactly the model in the Slewmaster thread. A working model by the way. 😎
 
i haven't seen his model but i believe that he did not had to assemble 19 amplifiers (inclosures,power supplies, heatsinks,in- out- connectors,protections:all of it x19) to get the idea,as i did. i get it slow...but i finaly got it.
.
ostripper is one more man(like Apex) that does not get out of ideas,i have his mongrel AX1,3vbc. very nice sounding,stabile amplifier that has also proven in measurements. great guy...
 
i haven't seen his model but i believe that he did not had to assemble 19 amplifiers (inclosures,power supplies, heatsinks,in- out- connectors,protections:all of it x19) to get the idea,as i did. i get it slow...but i finaly got it.
.
ostripper is one more man(like Apex) that does not get out of ideas,i have his mongrel AX1,3vbc. very nice sounding,stabile amplifier that has also proven in measurements. great guy...

You're right. I misunderstood you. The Slew master consists of an EF3 Ops that (plugs into) various IPS designs. One chassis, heating and PSU serving many different topologies.
 
it is all right - we understan each other in the end. 🙂

ostripper is a designer and he is many steps above my knowledge so he needs diferent chassis.

i,like many others, like to draw a pcb or two by given schematics and than to assemble it and listen how it works (right now i am listening APEX A23 and SR150),yesterday i was doing almost the same but trying to think my way to make costs of my hobby as low as possible and not to affect a quality of device - so i came out to idea not to buy PSU´s,protections,chassies,inclosures,heatsinks,connectors...in a same number as i plan to do amplifiers (by other designes/schematics) - cheapest as it can be and same,if not even more pleasure.

i can´t wait to do something on that point - allready have 1kVA EI transformer with winded primary - now i need to wind a few pairs of secondary windings,and three with thin coppeer wire,for symetric 15Vac to supply VAS and one with 12Vac to supply protection circuite. heatsink is something i will have to buy...

to tell you the throuth,i remembered you when you said that you have a lot of finished amplifier-pcb´s just sitting somewhere because you don´t have a time or will to do inclosures for them. something like this would make those pcb´s much often used and listened...

it is a good thing to have,besides Volt-Amper-Ohm meter,osciloscope and ton-generator.
 
Yes, I have maybe ten different Apex amps all attached to aluminum angles that I can clamp to a heatsink. I have a few different psu setups of various voltages and VA ranges. I also have an A/B setup for comparing two different amps simultaneously. These things are just tools to help me enjoy the hobby. I have about ten complete amps and two complete preamp in cases and probably 20 more working amp in PCB only form. Much easier to store populated pcbs than full amp cases not to mention the cost of all those power supplies, heatsinks and cases. I am struggling with these last few Apex amps because I got spoiled using board house pcbs with soldermask. I had forgotten how much of a hassle it is to search for solder bridges. Still, troubleshooting often helps to understand the circuit better so it is all good. I wish I had your talent for layout. Just can't seem to get my head wrapped around it.

Blessings, Terry
 
i am not so talented to draw layouts,i do it mostly "by muscles" ,not even close as easy as Olaf or AlexMM. as time passes by,i am more able to see similar stages of VAS or CAS and to use layouts allready done by this two excellent people and adjust them to a new design as i did for APEX A40.

i did (almost) completly alone without any help a PCB for APEX SR150 - output transistors and emitor resistors copied from Olaf,again,and VAS of it i did by my self.

it can be a terror to find soldier bridges,it happens to me to - it did on A23 - but a man should not push anything if it doesn´t go. i could not find it that evening and i left it for tomorrow,i believe that it is international saying "morning is more cleaver than the night",next morning i found it between C and E of pre-drivers... it happens,and patinetie is the best cure for it.

you said it right - that test-rig / chassies is a much needed TOOL,i am sorry for not having that idea much earlier... better ever than never! 🙂
 
Here is a picture of some of my Slewmaster projects. The heatsinks hold OPS sections that connect to different IPS boards you see sitting on the counter in front of them. Various CFA, VFA and some tube hybrid units as well. The large heatsinks hold a pair of identical 5P OPS so I can do A/B stereo tests with any two IPS topologies.

http://www.diyaudio.com/forums/atta...er-cfa-vs-vfa-rumble-slewmaster-obsession.jpg
 
Here is a picture of some of my Slewmaster projects. The heatsinks hold OPS sections that connect to different IPS boards you see sitting on the counter in front of them. Various CFA, VFA and some tube hybrid units as well. The large heatsinks hold a pair of identical 5P OPS so I can do A/B stereo tests with any two IPS topologies.

http://www.diyaudio.com/forums/atta...er-cfa-vs-vfa-rumble-slewmaster-obsession.jpg

Hey Terry I envy you 🙂 what a collection !!
 
list of album projects is in left vertical of Photobucket page:

44250's Library | Photobucket

APEX A23 100W 8r 180W 4r (27)
APEX F100 i SMPS (62)
APEX headphone amp (9)
APEX SR150 (21)
APEXaudio AX12 B80 (54)
APEXaudio G100 (42)
APEXaudio HV23 (57)
APEXaudio NX16 (63)
audio-signal generator (45)
Bato MM LM3886 u macolaKG-mostu (45)
Borin Staccato (29)
Borivoje Jagodic Clepsidra (22)
Borivoje Jagodic DOGC-H (93)
Borivoje Jagodic dogc-mk3 (30)
Borivoje Jagodic STUDIO- SE (53)
brzi elektronski podesivi osigurac (6)
ESP33 (9)
HiFi Hi-Power (5)
High Fidelity Lateral MOSFET Power Amplifier (6)
KG 2014 (15)
Lambda Amplifier
M O N G R E L 120 AX13 (21)
Marshall Lead 120 (17)
Michael Bittner SymAsym (40)
Mitar-amp i Milos-amp (67)
razno (36)
treference (12)
ZEN pojacalo za slusalice (1
 
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I would do a few of sir Apex's IPS's , they would be mostly compatible with
the EF3 OPS (terry did one , I think).

If sir Apex would approve , just a few tweaks to make compatible (5.3ma VAS) 🙂.

PS - I follow and am quite impressed with the APEX- xxx series of projects.

OS
 
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Yeah, I built an AX-14 as an IPS and hooked it up to the Slewmaster OPS. Sounds lovely.
 

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