nice boards. Double barrel balanced would be interesting. Idefixes, do you have any spare tubsumos?
Nice work Jeff!
I see an integrated protection system!
This will eliminate the wires a lot.
I think this is one of your best!😉
I've added an on board processor to this one and designed a softstart board with it's own processor. There's a rear panel connector with a USB port and processor selector. Just a couple ribbon cable making everything talk now.
This is designed to be a plate amp for an active speaker but I have a neat vertical chassis monoblock in mind for this one. Lots of mill work ahead.😀
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Great job! This is a solid module for driving some monster woofer section with top quality - 500W @ 4 ohm - no problem 😉
I'm curious how this will sound on full range speakers. It seems almost too good for subwoofer duty.
Kind of overkill if you ask me assuming it drives the sub actively.
Best used with difficult full range speakers. What's the bias and voltage range ?
Best used with difficult full range speakers. What's the bias and voltage range ?
Thanks for the info, right now it's lateral vs bipolar for me (considering Slewmaster too) and I will decide about IPS latter on.
With so many variants, I can only rely on Valery's and Jeff's comments about the differences of these. Would you say that dominant factor in amps character is the OPS selection or IPS can simply change everything so it's really the combination that maters
With so many variants, I can only rely on Valery's and Jeff's comments about the differences of these. Would you say that dominant factor in amps character is the OPS selection or IPS can simply change everything so it's really the combination that maters
The output stage determines how the amplifier is going to handle the load. The input stage determines the sound/personality of the amplifier.
Rick - a good question.
Just to elaborate a bit on Jeff's explanations.
In overall, OPS deals with high currents, always resulting in the highest and most noticeable types of distortion.
A separate story - very important one - the feedback organization. Voltage/current, single-loop or nested, etc. arrangements also determine the amplifier's character.
I prefer highly linear designs, using low amounts of global feedback, experimenting with no-global-loop designs these days - current-driven VAS is something I like a lot. I'm not saying the global loop is bad - everything is a compromise - but I seem to like the way low-loop-gain / no global loop amplifiers sound.
In both cases, OPS must be particularly good, as the effect of distortion reduction, provided by the global NFB loop, is either relatively low or not there at all.
Good amplifier must be fast enough - faster designs require lighter compensation, providing better sound. I started with some CFA designs with high enough slew rate, but then I came up with a number of CFA-fast VFA designs - using current-driven cascades, mentioned above - ensuring extremely natural sound.
Hope this helps 😉
Cheers,
Valery
Just to elaborate a bit on Jeff's explanations.
Right - OPS has to provide enough output current capability at required voltage swing. Assuming we use a well-engineered class AB OPS - the key issue is crossover distortion (related to Gm doubling in class A region) - a rather evil wide-bandwidth type of distortion. We use non-switching mechanism for significant improvements in crossover region, ensuring smooth "stitching" of two half-waves. High output current capability makes it possible to handle high loads (down to 2 ohm, if required).
In overall, OPS deals with high currents, always resulting in the highest and most noticeable types of distortion.
The front-end in many designs provides all the voltage amplification, being responsible for its "character". High linearity of every stage, the right gain distribution between the stages, minimal phase shifts, right impedance match, etc. ensure the low THD/IMD distortion levels and overall quality of the voltage amplification.
A separate story - very important one - the feedback organization. Voltage/current, single-loop or nested, etc. arrangements also determine the amplifier's character.
I prefer highly linear designs, using low amounts of global feedback, experimenting with no-global-loop designs these days - current-driven VAS is something I like a lot. I'm not saying the global loop is bad - everything is a compromise - but I seem to like the way low-loop-gain / no global loop amplifiers sound.
In both cases, OPS must be particularly good, as the effect of distortion reduction, provided by the global NFB loop, is either relatively low or not there at all.
Good amplifier must be fast enough - faster designs require lighter compensation, providing better sound. I started with some CFA designs with high enough slew rate, but then I came up with a number of CFA-fast VFA designs - using current-driven cascades, mentioned above - ensuring extremely natural sound.
Hope this helps 😉
Cheers,
Valery
That's true, partly at least. Some people swear by laterals, having heard them, it's true that they sound special although I'm not mosfet lover. I think bipolar are more or less chameleons.
Anyway, which of your designs have the most natural sounding, lateral or lapt OPS ?
One of the many times built / auditioned configurations is NS Modular + Vertical CFA front-end. I also like NS Modular + X4 a lot. This is one of rather unique CFA-fast VFAs.
We've got a few new designs in the pipe, but those still need proper testing.
The other great combination is NS OPS + TubSuMo front-end. Extremely natural sound. If you're ok to have a tube at the input 😉
Cheers,
Valery
Agree go for NS,using one cfa VX4 and one VFA you will have your own opinion.
I can say nothing about TubeSuMo as i hadn't the opportunity to listen this IPS.
Valery and Jeff have designed some new IPS but i haven't test any due to many missing parts.😡
I can say nothing about TubeSuMo as i hadn't the opportunity to listen this IPS.
Valery and Jeff have designed some new IPS but i haven't test any due to many missing parts.😡
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The Vertical CFA is still my favorite input to date. It's very natural sounding. I have a backlog of Valery's newer designs sitting on the bench waiting proper testing though, so my opinion might change. The AX-Deluxe is very good too.
I've only built a couple amps with LatFets and both amps didn't really impress me. I think it may have been due to fake LatFets though. I prefer to build with parts I can buy from a reputable supplier. That pretty much eliminate LatFets in north America.
I've only built a couple amps with LatFets and both amps didn't really impress me. I think it may have been due to fake LatFets though. I prefer to build with parts I can buy from a reputable supplier. That pretty much eliminate LatFets in north America.
Thanks guys for the info.
Was there any through hole version of NS-OPS ?
Vallery, evolution is part of the game but as far as options is concerned there are plenty. In other words, take a brake 😎
Was there any through hole version of NS-OPS ?
Vallery, evolution is part of the game but as far as options is concerned there are plenty. In other words, take a brake 😎
The NS-OPS has been mostly SMT parts from the first board design. There are a lot of parts to these. They would be huge in through hole.
with the middle leadout of the plastic package being the Source, it is pretty difficult to fake a Lateral mosFET.
They would have to use another Lateral as the starting device and fake the package.