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Old 13th November 2009, 11:47 PM   #11
col is offline col  Australia
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Quote:
Originally Posted by dubai2000 View Post
col,

you also use a TA3020 amp if I'm not mistaken. Do you care to elaborate on the sound differences between those amps? Your response will be appreciated - thx in advance.
Hi Dubai2000,

Yes, I have a ConnexElectronic TA3020. I am powering it with a toroidal and PSU that I had from a UcD180 project that didn't get completed so power is lower than my UcD400. I haven't done any blind tests and I am not good at doing subjective comparisons. I prefer the engineers approach of comparing the spec. Both sound very good and the TA3020 is better bang4buck.

col.
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Old 14th November 2009, 08:29 AM   #12
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Hi col,

thanks for your answer. I agree that the TA3020 is a great amp. Btw: I noticed on your website that you have not done any mods to your amp. In my experience its performance can be improved if a few caps are swapped.
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Old 28th November 2009, 03:45 AM   #13
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Just for fun, I did a 150 Hz up listening comparison today between my Hypex UcD400ST amp and an old school Conrad Johnson MV55 valve amp in triode configuration (22W/channel). My test speaker set-up does not lend itself to a full-range comparison as the passive crossovers are hacked for active bi-amplification. To my ear, the CJ was immediately and unequivocally superior in terms of musicality and enjoyment. My Hypex amp sounds quite clean and precise, but lacks weight and sounds extremely "thin" and uninterestingly clinical compared to the CJ despite it being specified as having about ten times the power capability and much lower distortion figures. It performs reasonably well for bass frequencies, but nothing to write home about - again - to my ear - a little lacking in authoriy. A CJ MF2500A's bass performance is better on my set-up. I can't imagine capacitor or regulator changes making the modules sound less sterile. The problem might not be in the modules themselves, but in my implementation of them - but I doubt it. Next time, if I want to listen to a computer, I will.
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Old 28th November 2009, 11:17 AM   #14
teflon1 is offline teflon1  Denmark
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Ian,

You demonstrate some interesting logic here, to have started with their worst version to save a dollar on your bass quality, after having presumed it wouldn't matter, and then judge the known compromised setup in full range use. According to your site you had it prejudged anyway, having said you'd never use it for full range, so this seems like a self fulfilling prophecy at least.

As icing on the cake you doubt improvements could make it better, and further doubt your own implementation is above reproach. It's not the worst I've seen but it can be improved, and your stock, standard grade modules, most certainly can.

Even were it relegated to bass I don't see why you'd use bog standard, cheap electrolytic coupling caps, and without even any bias across them. Of course, you've already concluded caps can't make a difference. It seems you have some work to do. Nothing of this is news, it shouldn't come as shock to you now.

Your computer comment makes the least sense of all, but it seems you're standing on your toes to make that reach. The problem is both the version of module you chose, and your use of them. You wouldn't garbage pick out of the dumpster of a five star restaurant and then write a bad review, or would you?

Since you know nothing of caps or anything and seem unwilling to make an effort you'd have done yourself well to pony up the extra money to get the high quality version, but bass doesn't matter, right?You'd do yourself well with a little bit of effort, and perhaps with the intent of seeing what is possible, rather than trying to prove your prejudice, of which you did an excellent job.
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Old 30th November 2009, 10:06 AM   #15
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Originally Posted by teflon1 View Post
You'd do yourself well with a little bit of effort, and perhaps with the intent of seeing what is possible, rather than trying to prove your prejudice, of which you did an excellent job.
Must have hit a raw nerve, but clearly Plastic Boy either can't read or can't understand a logical expression of an alternative viewpoint, so what the heck.

For the benefit or others:

In his ill-tempered fit of bad manners with false presumptions and misinterpretations he missed my simple point which was that the sound (the way I hear it) of the cheap ST modules is already too clean and precise - which some/most people might like. My opinion (and I assume I am entitled to one) is that such a sound is clinical, thin and uninteresting and therefore certain so-called "upgrades" of caps and power supply regulators might make them sound even more clean and precise which would bother me. I'm allowed to express a doubt that they would have any effect and don't have to waste time and money on an experiment to prove an irrelevance.

IMO the ST modules are the appropriate choice (cost-wise) amongst the direct alternatives for bass application in a multi-amp set-up, or for subwoofers. Upgraded coupling caps and regulators (for a mere input buffer opamp!) would have no audible impact at these frequencies whatsoever. If PB were to do his homework, he might even learn that they are used by the manufacturer in their subwoofer plate amps. The reasons for that are clear and obvious to me.

BTW, my post started with "Just for fun" - so what is this about anyway?

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Old 30th November 2009, 10:11 AM   #16
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Originally Posted by Ian Millar View Post
IMO the ST modules are the appropriate choice (cost-wise) amongst the direct alternatives for bass application in a multi-amp set-up, or for subwoofers.
I'm with you on that.
So it'd be wise to stick to that use and not for "150Hz up listening comparisons" or, at least, if you do so, don't jump into conclusions about what the higher grade modules can do.
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Old 30th November 2009, 11:04 AM   #17
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... don't jump into conclusions about what the higher grade modules can do.
As far as I know, expressing a doubt is not the same as jumping to a conclusion.

Anyway, another point is that by the time you've spent the extra money on the higher grade modules (and even say the third party off-board regulator upgrades) and the very costly SMPS power supplies, you've moved right into and beyond the price realm of many proven alternatives, but still have a Class-D amp.

Say for bi-amping where you don't need high power for the upper range where the differences might be audible, then Class-A kits would have to jump out as logical contenders. And they could be repaired by people with ordinary diagnostic and soldering skills if something went wrong down the track. I don't know anybody who can repair a computer motherboard and the modules are just as packed.

For full range speakers with passive crossovers (i.e. just a single stereo amp), I concede that cost-wise, the ColdAmp modules or the Hypex UcD400HG etc. might be a logical starting point if you wanted that "clean" kind of sound and were prepared to regard them as disposable on failure.

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Old 30th November 2009, 11:33 AM   #18
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Originally Posted by Ian Millar View Post
...the very costly SMPS power supplies
Indeed, the Hypex SMPS power supplies are too expensive. Thankfully there are alternatives out there (and you can always go for a linear power supply).

Quote:
Originally Posted by Ian Millar View Post
you've moved right into and beyond the price realm of many proven alternatives, but still have a Class-D amp.
Indeed.
But, trust me, I've seen (or actually, heard) many "proven alternatives" eat Hypex dust.

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regard them as disposable on failure.
I have no idea about Coldamp but, in my experience, Hypex have excellent after-sales support.
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Old 30th November 2009, 01:37 PM   #19
fb is offline fb  Australia
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Any suggestions as to alternative SMPS suppliers? Red Rocks are proving hard to get in contact with.
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Old 30th November 2009, 03:35 PM   #20
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RedRocks are hard to contact nowadays. They must have shifted to bulk orders or something..

Check out connexelectronic (these guys have a thread in the vendor forum) or Coldamp. ClassDaudio will soon release their own SMPS. I'm sure others will have more suggestions.
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