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$500 amplifiers to test and review?

Sal1950

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It's amazing they buried such a useful part of the OS.
Windoz don't want you having that much power and allowing knowledge of these switches, your not worthy. :p
 
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From the specs, I don't think it will be any different than the A500 that I have. So I don't think it pays to ship it back and forth.
Oh interesting, wasn't aware you were going to review the A500. They do appear to be pretty similar, although the KM750 it rated for a bit more power and outputs / rear panel setup is a bit different. Internal layout is a bit different as well, the KM750 appears to have a smaller transformer and relies on active cooling instead of the larger passive heatsinks in the A500.

I'll be looking forward to the A500 review, thanks @amirm.
 
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I second this request.

I've been thinking about replacing my early 90's vintage (and super inefficient) Adcom GFA-535 II amp with this one or possibly the kit version of the same amp. The kit version saves about 60 bucks, but in either case, this looks to be a great bang-for-the-buck amp, assuming of course that it measures well and sounds decent.
 
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amirm

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VMAT4

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amirm

amirm

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Too bad the complete bill of materials isn't readily available to all.
IEEE is really bad in allowing public access. Even if you are willing to pay, they charge far more than other organizations for access to their documents. I have complained to them at shows and they just give me the look of "what are you talking about?" Companies usually pay for their fees and for them it is affordable.

To the extent they get all of these papers for free from authors, it makes no sense to me that they charge a ton of money for electronic access. In the days of print, it made some sense but not for electronic downloads.
 

Sal1950

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o_O?????o_O
Don't know what schools you guys went to?
But everyone knows that a grade of A, or even A-B, is much better than a D.
D is just above a failure. :eek:
 
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o_O?????o_O
Don't know what schools you guys went to?
But everyone knows that a grade of A, or even A-B, is much better than a D.
D is just above a failure. :eek:
Well, that was the conventional wisdom, but more recently, there has been high praise for modern Class D designs, particularly class D amp modules from Hypex, ICEPower, Pascal Audio and others.

Note that PS Audio's Stellar M700 power amp uses an ICEPower 700AS1 class D amp module, and Stereophile indicated it has respectable measured performance. Similarly, the Mytek Brooklyn Amp, which sports a modified Pascal Audio class D amp module, also measures respectably. Hopefully, Class D Audio's CDA-250C will demonstrate decent measured performance as well.

Just as important (at least for me) is the much cooler operating temperatures that typically comes with a class D amp. Due to spousal acceptance factors, I'm forced to stuff my Adcom GFA-535 II (which is a class A or A-B hotbox) in an enclosed cabinet; it gets waaay too hot in there to be healthy for my other components or for my record collection (stored in the same cabinet).

Anyway, looking forward to Amir's testing of the CDA-250C!
 
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restorer-john

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Don't know what schools you guys went to?
But everyone knows that a grade of A, or even A-B, is much better than a D.
D is just above a failure.
Hitachi had some Class G amps. I have one (an HMA-8300) in my storeroom- 24kg of obscene power in a big black box with meters.

8300.JPG


Those capacitors are bigger than a beer can, but not as enjoyable as beer. Did someone say beer?
 

DuxServit

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Just had to boot into my Win 10 partition to do a Windoz only thing. Hadn't booted into doz for all of about 24 hours.
Took about 15 minutes for the drive to quit grinding away on some update before I could do anything.
I HATE Windoz 10 :mad::mad::mad::mad::mad:
Dump Win10 and go back to Win7. That’s what I did, and I even bought a spare Win7Pro retail box. When people ask me nowadays what PC desktop to buy, I always say buy one that still lists Win7Pro as an option (downgrade or disk included).
 

restorer-john

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Dump Win10 and go back to Win7. That’s what I did, and I even bought a spare Win7Pro retail box.
I did the same on all but two machines which are win10. I use win10 for my 'less-than-technical' friends and for my elderly parents as it genuinely does allow for a true set-and-forget operating system.

I have major fundamental issues with the mess that is Win10, from the ridiculous number of monitoring processes to the deprecation of functionality, all hidden in a wreck of a malformed and ugly UI.

Win7 is/was a joy to use, just as WinXP was the same 10 years prior. Like yourself, I'm sitting on a bunch of Win7 home retail boxes, although MS could kill the registration/activation/core updates down the track and I'll be stuck with pre last service pack installs.
 

Sal1950

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Win7 is/was a joy to use, just as WinXP was the same 10 years prior.
Hell I ran XP until just a year back when Quicken refused to run updates any more due to security code issues. IMHO XP was the best Windoz ever, very intuitive and user friendly. Too bad they can't keep the code clean, it becomes more and more bloated with code errors till they have to wipe the slate clean with a new OS that has to be learned and isn't as good as the one before.
 

josh3010

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maybe some integrated tube amplifiers like the ones from Nobsound and Gemtune on amazon? I'd love to see how tube amps compare to solid state and digital amps
 

sergeauckland

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maybe some integrated tube amplifiers like the ones from Nobsound and Gemtune on amazon? I'd love to see how tube amps compare to solid state and digital amps
In a word, badly, but there's a huge difference between the 'better' valve amps using PPUL outputs with really good (and expensive) output transformers and a decent amount of feedback and SETs, especially those with no feedback, where it's hard to make them do anything well technically. That's why SETs were already obsolete by the 1920s.
Some valve amps, like Radfords and RCAs can be good enough for transparency, but that's rare, and anyway, why would anyone buy a valve amp if it sounded the same as any other common or garden SS amp? Modern valve amps have to have a distinctive sound, which is what people buy into, and can't try for 'fidelity'. Looks too of course!

S
 
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amirm

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maybe some integrated tube amplifiers like the ones from Nobsound and Gemtune on amazon? I'd love to see how tube amps compare to solid state and digital amps
I have a Nobusound DAC for review. Just tested it a bit. If their amps are they same, they are not worth measuring!
 

Sal1950

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I find it interesting that the price only goes up $300 for the 5 channel version over the 2 channel.
I agree with the clean inside wiring statement but whats that got to do with the outside wiring hell of a 5 channel rig (or a 11 like mine)? :eek:

"Spaghetti Free Zone
Ever look behind a stereo rack and were aghast at the sight of the spaghetti entanglement of dozens of wires? Not here. Neat, clean wiring in tubing designed for the aerospace industry. Clean wiring. Clean layout. Better sound."

 
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