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Old 26th September 2005, 01:29 PM   #921
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Quote:
Originally posted by plovati

How gone that it is in Australia now?
Piergiorgio
Actually it is in Texas. USA
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Old 26th September 2005, 01:56 PM   #922
plovati is offline plovati  Italy
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Ok, I realized now that the photo comes from Panelhead, and Mau_Auf just help him to shrink the images down.

Mine was just curiosity, this DIYaudio is worldwide wired...
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Old 26th September 2005, 02:13 PM   #923
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Quote:
Originally posted by plovati
Ok, I realized now that the photo comes from Panelhead, and Mau_Auf just help him to shrink the images down.

Mine was just curiosity, this DIYaudio is worldwide wired...

Absolutely. I was amazed how many REV As went out all over the world. I think I sent boards to every continent, except antarctica.

Cheers!
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Old 26th September 2005, 02:41 PM   #924
doggy is offline doggy  Canada
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Good morning Russ;

Just a few questions: With the pcb and kit; are the power supply caps included and the diode rectifiers? Also what would you recommend for a transformer? I have an old working center tapped trans. pulled from a 70's Kenwood amp.

I have a lm3875 and lm4780 amp.In a few words;what do you feel are the major sonic improvements with the new amp.The lm4780 is my favourite now.

Thanks;
doggy
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Old 26th September 2005, 02:56 PM   #925
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Hi Doggy,

The LM3886 can drive more current than the LM3875, but they actually sound very similar. The 4780 is nothing more than two LM3886 dice in one package. So if you like the LM4780 you are really saying you also like the LM3886.

For our kits all of the PS parts which go on the PCB are included (caps, bridge, etc...) but you will need your own trafo.

48VCT is ideal (250-300VA is big enough for stereo), or 24V dual secondaries. It is OK to go a little lower voltage say 21-22V secondaries, but you will have less headroom.

The major benefit to REV_C is that it has some of the flatest frequency/phase shift behaviours you will ever see. That translates to good imaging, and faithful accoustics with faithful reproduction without the detriment of nasty phase shifts which are common in many amps.

Cheers!
Russ
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Old 26th September 2005, 03:10 PM   #926
troystg is offline troystg  United States
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Russ/Mauro-

The GC amps usually benefit from a buffer driving them.

I am currently planning on going passive 50K noble pot and relay input switching but I have a pair of Pavels "audio refiner" brds if the buffer is necessary.

Should I plan to implement Pavels boards or will the 50K pot be sufficient?
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Old 26th September 2005, 03:15 PM   #927
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Quote:
Originally posted by rabstg
Russ/Mauro-

The GC amps usually benefit from a buffer driving them.

I am currently planning on going passive 50K noble pot and relay input switching but I have a pair of Pavels "audio refiner" brds if the buffer is necessary.

Should I plan to implement Pavels boards or will the 50K pot be sufficient?

Hi troy, a buffer will not hurt, but it is not necessary (the only exception would be if you had a source with very very high output impedance), because on this power amp the input impedance is high (100K). So your source does not have to pump much current.

50K pot is just fine, but I actually use a 10K pot when I am not using a preamp.

I have a few inverting GCs which absolutely require a buffer for good operation, in that case Pavels boards are a very solid choice, but this amp (MyRef) is not like that.

Cheers!
Russ
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Old 26th September 2005, 03:16 PM   #928
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Quote:
Originally posted by rabstg
Russ/Mauro-

The GC amps usually benefit from a buffer driving them.

I am currently planning on going passive 50K noble pot and relay input switching but I have a pair of Pavels "audio refiner" brds if the buffer is necessary.

Should I plan to implement Pavels boards or will the 50K pot be sufficient?

I Am running a 100K on its own without any problems.

strangely (or maybe not) I have tried a AD815 pre in front of this amp and i found that it degraded the sound somewhat but not much. i prefered the sound with the passive.
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Old 26th September 2005, 03:23 PM   #929
doggy is offline doggy  Canada
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Thanks Russ;

Thanks for replying so swiftly!it's to your credit. I have a few more amps around where I can pull off parts.

doggy
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Old 26th September 2005, 05:25 PM   #930
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I just posted a BOM for the parts kit, for those interested.

RevC Parts Kit BOM
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