Need a little advice on some AR Mono Block Amplifiers...and Speaker wires

Bucknekked

Bucknekked

Audioholic Field Marshall
You shouldn't be so 'trigger happy' on the 'plagued with haters' labels to label people with firm stands, which seems to be very popular these days.
killdozzer
The particular user you referred to (Got HiFi?) became very trigger happy the other day. After a discussion like this one where his opinion was not held in high esteem, he went on a graffitti campaign against most of the users in the thread. I personally got 26 of my posts marked "DUMB" in less than 2 minutes. Others saw the same graffitti by a trigger happy immature individual. I believe he is no longer able to post.

He is probably selling high end cables right now to an unsuspecting housewife.
 
Bucknekked

Bucknekked

Audioholic Field Marshall
Your friend needs deep therapy. He has obviously been fleeced for years by a high end "Audiophool" dealer. Its a good thing he has now closed his doors.
TLS Guy
What a great post. Informative. Logical approach. Line by line reasoning. Good, relevant data that was on the topic and not just drowning the reader in trivia. I don't know what you do for a living, or how you amassed this level of detail in your audio toolkit, but dang ! If I run in to a problem, I am hopeful I will have access to someone like you for some help.
 
TLS Guy

TLS Guy

Audioholic Slumlord
TLS Guy
What a great post. Informative. Logical approach. Line by line reasoning. Good, relevant data that was on the topic and not just drowning the reader in trivia. I don't know what you do for a living, or how you amassed this level of detail in your audio toolkit, but dang ! If I run in to a problem, I am hopeful I will have access to someone like you for some help.
Well, I'm already out to pasture, I turned 70 10 minutes ago. I'm a retired physician, but have been in audio a long time. I stated building speakers and circuits at around seven years of age. Anyway it has been in interesting journey pursuing what Peter Walker called "The Closest Approach to the Original Sound." That was the slogan he coined for Quad Electroacoustics.

I'm also a bit of a hoarder and don't get rid of my gear unless it is totally beyond restoration. So my systems end up being current and part museum.

I started off around four years old with an acoustical gramophone that was built in India of all places. My father bought it out there and brought it back with him when he returned after WW II. He was a Captain in the Royal Engineers, but was sent out to join the Indian army to defend against Japanese invasion. The main spring eventually broke on that machine. After that I got serious.

You can see some of the gear I have accumulated over a life time if you like.

AV studio.

Downstairs system.

Vintage turntables and cartridges.

Eagan residence systems.

The Jordan Watts modular full range loudspeaker. (first produced 1959)

I'm just grateful to have lived so long and seen this extraordinary technical progression. I can now stream and download concerts from around the world with a glorious picture and sound.
A remarkable run providing enormous enrichment to life.
 
killdozzer

killdozzer

Audioholic Samurai
Check again.
His words Not that all high end cables are bad (this forum seems to be plagued with cable haters) ..

But Then, I may be reading something else.
No, no, I know, I've been sarcastic, of course he wrote it. Sorry, I didn't use any emoji so it wasn't obvious and these days you really need to use'em. I was just making a joke like; since he's so confident he didn't write it, I'll trust him over myself. :D I mean, that very sentence you paste in bold would imply that people here say all high end cables are bad but he is not making that mistake. It also implies that a statement like: "very expensive cables have been nothing but a scam so far" can be written only by a cable hater. It is obvious what he wrote, although without the brackets he might have got off scot free.

killdozzer

He is probably selling high end cables right now to an unsuspecting housewife.
You had me actually laughing out loud!

I had that feeling about him, however, sometimes I'm wrong and I saw he just joined a few days back so I wanted to tell him that this is not a community where people would rather sulk and not buy something that is really better for the sake of... I don't know what... some dogma or something? Considerably better and reasonably priced is what it's all about.

When he said I'm illiterate (or perhaps he never said that :D ) I didn't want to continue. Lately I've been getting a Feeling I'll end up on bad terms with the entire planet.

cheers!
 
Bucknekked

Bucknekked

Audioholic Field Marshall
Well, I'm already out to pasture, I turned 70 10 minutes ago. I'm a retired physician, but have been in audio a long time. I stated building speakers and circuits at around seven years of age.

I'm just grateful to have lived so long and seen this extraordinary technical progression. I can now stream and download concerts from around the world with a glorious picture and sound.
A remarkable run providing enormous enrichment to life.
what a wonderful set of items to take a tour of. I took the tour. wow. now that's a wonderful collection.
I am not far behind you at 62 years of age, but I am worlds away in my audio gear collection.
In the Eagan System, slide 17, it looks like you have a channel master DVR unit. For over the air HDTV signals. I have one of those too. I love it. Cut the cable 2 years ago. went HDTV over the air with a channel master DVR for the guide and recording.

Thanks for the tour
 
-Jim-

-Jim-

Full Audioholic
Gents,

Thanks for the various opinions. I'd really like to help my friend solve this mystery. However he's a Mechanical Engineer who somehow believes in those MIT cables passionately. Of course the issue at hand is to once again get the failed AR Amp repaired. I've prodded him that doing the same thing over and over and expecting different results is insanity. He's a proud man, and for him to back away from his beliefs after all these years would be a tough process.

I'm just a licensed Electrician with a year of Electrical Technologist training that he looks to for all his electrical and computer support. (I build and repair PCs as a hobby for Friends and Family as well as do Satellite TV installs for them as well).

My first inclination (after the Amp repair) would be to remove those cables and try to eliminate that as a cause of the problem. It's a simple move and not costly.
 
TLS Guy

TLS Guy

Audioholic Slumlord
Gents,

Thanks for the various opinions. I'd really like to help my friend solve this mystery. However he's a Mechanical Engineer who somehow believes in those MIT cables passionately. Of course the issue at hand is to once again get the failed AR Amp repaired. I've prodded him that doing the same thing over and over and expecting different results is insanity. He's a proud man, and for him to back away from his beliefs after all these years would be a tough process.

I'm just a licensed Electrician with a year of Electrical Technologist training that he looks to for all his electrical and computer support. (I build and repair PCs as a hobby for Friends and Family as well as do Satellite TV installs for them as well).

My first inclination (after the Amp repair) would be to remove those cables and try to eliminate that as a cause of the problem. It's a simple move and not costly.
Some people are beyond help. If he takes a dispassionate look at his situation he must see that he has a lousy system, that in its totality is junk, if for no other reason than it is unreliable. I doubt it sounds anything like as good as its phenomenal cost should dictate.

One clue here is that he says his LPs sound better the digital. He may be right about that. When this happens it is because digital sources have among other attributes much wider dynamic range and stress a system much more severely. On a good and properly set up system good digital sources sound significantly better than LP no matter how much the turntable costs. If his sounds better on LP, and I fully expect it does, that is an indication his system is far short of state of the art.
For one thing those speakers are totally unsuitable for driving with a tube amp. And to be honest they are not very good speakers anyway.

I can assure you that my system with good digital sources bests the old LP by miles.

This chaps pride is wasting a ton of money and denying him the huge pleasure of the AV world.

I turned 70 today and I am always pushing like long learning. Your friend has some catching up to do.
 
TLS Guy

TLS Guy

Audioholic Slumlord
what a wonderful set of items to take a tour of. I took the tour. wow. now that's a wonderful collection.
I am not far behind you at 62 years of age, but I am worlds away in my audio gear collection.
In the Eagan System, slide 17, it looks like you have a channel master DVR unit. For over the air HDTV signals. I have one of those too. I love it. Cut the cable 2 years ago. went HDTV over the air with a channel master DVR for the guide and recording.

Thanks for the tour
Yes, it is a Channel Master DVR and a superb unit,
 
-Jim-

-Jim-

Full Audioholic
Wow Gents! I didn't expect this kind of response. Lots of venom being sprayed about. But at least it got you all thinking about the problem.:rolleyes:

I went over for a visit today, and the left Audio Research Mono Block Amplifier is still dead, as my friend just recently found a "local" authorized repair person certified by AR. (In the past he packaged them up and sent them back east to AR in the USA.) The repair guy lives in Edmonton, and vacations in the Gulf Islands here in BC; so he will pick it up on his next trip west in a month or so.

In all of the failures AR said it could not identity what was causing the issue. On 12 of the failures the input was the turntable, and two were the Mark Levinson CD Transport. So it's not consistent based on input. I've got photos but can't up them here so I found links to existing pics around the web.

My friend babies this system an would never unplug cables when energized. He warms up the system for a few minutes before listening to anything. It's quite a ritual when he does it. He was talking to his security technician (he's got about 30 wireless cameras all over his property) and he suggested the RF from those devices may be causing the problem. I don't see how as everything is shielded but what do you think?




Speaker Cables are CV Terminator Twin MH-770 like the photo below but they don't have Tube on them. I think the left one was weeping something out from a screw on the back. (I assumed it was a capacitor failing but I don't know what's inside these things.) I'm trying to convince my friend to removed these and try "regular" cables once the Amp is repaired. I think this would be the easiest item to eliminate.

My friend is one of those convinced the MIT Cables work. His vendor sold a few systems like his when he bought his (mostly to Russian Mafia types he said) and not one had any issues.



Here's what the Speakers look like:



And the AR Amp:



Here's the manual (such as it is) http://www.audioresearch.com/ContentsFiles/REF600 Manual.pdf

Any help would be appreciated.

Thanks for the assist.:cool:
 
-Jim-

-Jim-

Full Audioholic
Hi Gang,

I thought I'd update you on this saga. My friend sat on the repair of the AR Amp for 2 years but finally got it back. I think he's finally convinced there is something fundamentally wrong with his system. I've convinced him to remove the MIT MH-770 cables at they aren't adding anything to his system, and may be part of the problem.

However, when I tried to discuss the possibility of an incompatibility between the AR Amps and his Wilson Maxx Speakers, he said he knew of 2 or 3 guys in Greater Vancouver who bought the same set-up he did, and they never reported any issues. He said the Vendor (I think it was the Sound Room in North Vancouver) some years ago said they never had any issues with either of these components (with or without MIT cables) but couldn't find anything wrong when they sent a "Tech" to investigate after the first of many failures. Wilson didn't have any comments on the system ahead of the Maxx Speakers when they sent a Tech to set up the speakers when first purchased.

My friend mentioned that his Security Tech advised that he thinks it could be RF noise from the VHS radios on the Boats / Ships going by as my friends house is right on the water near Deep Cove. I thought this sounded preposterous but of course kept that to myself, and simply said I doubted that was the cause.

I did find out that they are using about 15 foot RCA Cables to interconnect the AMP & Preamp. I'd think that at this distance Balanced Cables would be a prudent fit if the devices could accommodate. (In the AR manual on page ii it shows a 200 K Ohm Balanced input.) It's just another thing to eliminate at low cost.
 
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Mikado463

Mikado463

Audioholic Samurai
Jim, your friend remains in denial, there is no hope, call for the white coats asap .............
 
Pogre

Pogre

Audioholic Overlord
Hi Gang,

I thought I'd update you on this saga. My friend sat on the repair of the AR Amp for 2 years but finally got it back. I think he's finally convinced there is something fundamentally wrong with his system. I've convinced him to remove the MIT MH-770 cables at they aren't adding anything to his system, and may be part of the problem.

However, when I tried to discuss the possibility of an incompatibility between the AR Amps and his Wilson Maxx Speakers, he said he knew of 2 or 3 guys in Greater Vancouver who bought the same set-up he did, and they never reported any issues. He said the Vendor (I think it was the Sound Room in North Vancouver) some years ago said they never had any issues with either of these components (with or without MIT cables) but couldn't find anything wrong when they sent a "Tech" to investigate after the first of many failures. Wilson didn't have any comments on the system ahead of the Maxx Speakers when they sent a Tech to set up the speakers when first purchased.

My friend mentioned that his Security Tech advised that he thinks it could be RF noise from the VHS radios on the Boats / Ships going by as my friends house is right on the water near Deep Cove. I thought this sounded preposterous but of course kept that to myself, and simply said I doubted that was the cause.

I did find out that they are using about 15 foot RCA Cables to interconnect the AMP & Preamp. I'd think that at this distance Balanced Cables would be a prudent fit if the devices could accommodate. (In the AR manual on page ii it shows a 200 K Ohm Balanced input.) It's just another thing to eliminate at low cost.
I think that TLS' post number 4 in this thread pretty clearly lays it out. That impedance chart is crazy, and I can't believe anyone would manufacture a speaker in that price range (or any) with behavior like that. Your friend needs more capable amplification, or better yet new speakers.

I don't know anything about those cables, but if you open those boxes up they're so filled with glue you can't even see what they did. I think that's likely on purpose too.
 
Mikado463

Mikado463

Audioholic Samurai
a personal footnote on Wilson speakers....... While I still am not at all enamored with their looks and have never studied at length their freq and imp curves I will say that current offerings that I've listened to sound good and I assume present a much easier/stable load for amplifiers. Kinda reminds me of modern Martin Logans, having gone to hybrid design they too are far less finicky when it comes to amplifier selection.
 
Pogre

Pogre

Audioholic Overlord
What's really telling is, he's willing to explore possible RF interference as being the problem when that impedance chart in post #4 is one of the worst I've seen in any speaker. You should show your friend that chart and explain those phase angles to him. I have never seen a speaker literally go off the charts like that.
The first is that the impedance actually drops to almost 2.0 ohms where there is a lot of power required at 250 Hz. Now I would be strongly suspicious that that reading is lower then the DC resistance of the drivers at that frequency. If that is so then the crossover is in resonance. That alone would explain your friend's difficulty.

But there is another serious problem.the phase angle is going off the bottom of the chart at 6 KHz. It is -90 degrees and still heading south. This means there is a huge gap between voltage and current phase. Now this is just the sort of thing well known to send tube amplifiers in to ultrasonic oscillation. The oscillation is well above the range of human hearing. This problem really blows up tube amps.
Maxfig01.jpg

I now notice something I had not noted before. I noted the phase angle heading south, at 6 K and disappearing. Now I note it reappears, and heads above +90 at 12 K and back down to -20 by 20 K. There is something really rogue with that speaker design in the last two top octaves. That is just the ticket for blowing up a lot of tube amps. As I think about it this is likely the cause of these repeated catastrophes.
 
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lovinthehd

lovinthehd

Audioholic Jedi
What's the fun of esoteric high end speakers if they're not a weird load on the amp, tho?
 

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