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Class "A" sound, as related to Stereophile.


It's all about the sound.

It's all about sound, not how much it cost; when I got into "high end", I knew right off the bat I couldn't afford it, but I had to find one thing for sure; how do the various components sound in regard to Stereophile's classes, or ratings? In order to know this; I had to acquire the ability to identify "Stereophile's" class "A" class "B" and class "C" sounds, and the only way to do that was: first, subscribe to Stereophile, and next was to go to every high end audio salon within driving distance; there were 5 well stocked "high end" salons within driving distance. (Since I didn't take my wife, that created some problems)

After a few years of subscribing to Stereophile, plus auditioning equipment that Stereophile recommended, I knew the sound of those recommendations, and I absolutely concurred with them; "If you want to hear the music, you got to pay the piper". While that's true, it's possible to get class "A" sound with class "B" bucks or less.

At this moment, I am looking at 8 capacitors that cost $25 dollars each, plus 2 mono blocks with an instant resale value of 6K. Once I take the covers off and go in with my soldering iron, these mono blocks are worth a resell of O; my mission must be a success. After a successful mission, the resell is still 0; but those mono blocks will deliver class "A" or "A"+ sound, and that's some sweet music.

I have to visualize and hear music in my head before I can modify a component to deliver class "A" sound; but that's the only way for me to get what has become a necessity.

The pressure someone is under when they modify, is great, but the rewards are glorious. On these mono blocks, they are too small for the huge capacitors, therefore I have to figure a way to make the case larger. My reward is "sound" with absolutely no relation to money. I often wander if someone with a fat bankroll can identify the sound, or only how much they paid for each piece.


Happy listening.

orpheus10
orpheus10 OP
8,668 posts
 

Dave, have you been through room acoustics? Can you make specific recommendations? I've seen different things, but I don't know what does what.


Thank you.
dlcockrum's avatar
dlcockrum
2,190 posts
 
Hi o,

I had a tremendous mid-bass hump in my room.  Spent many days rearranging speaker and listening positions and measuring the resulting frequency response, all to little avail.

I did some research on another website (something asylum) and found a lot of good information from Jon Risch. He made a strong case that bass traps should be made of 2" thick rigid fiberglass completely sealed to the corners so that it actually traps the overabundant bass waves.

So I found a local building supply warehouse nearby and bought 24" wide X 2" thick rigid yellow fiberglass panels as long as they had (6' long maybe?). This is not the loose pink stuff you buy at HD. It is very dense and rigid.  I bought frame material, something like 2" wide plywood board from HD to make the frame completely around each panel and built them the exact height of my room from floor to ceiling.

After the frame was added around the entire circumference and fiberglass panels, I used spray-on adhesive and a staple gun to attach fabric that I bought cheap to the panels.  I found soft butyl rubber garage door gasket at the local Ace (the kind that is used for sealing the bottom of garage doors) and trapped that all the way around the panels (no gaps) into the corners of the room behind my speakers. I had cut strips of wood to brace them into the corners every 2 feet vertically.  You can see pics of these on my Virtual System page. 

I also built 2' X4' panels of the same 2" rigid fiberglass using the same framing and fabric technique, but not sealed, and placed them at  the first refection points halfway between the speakers and my listening position.

Worked like a charm. My audiophile friends could not believe the improvement.  Total cost was around $500 and it took a few days to build them all.

Best to you o,
Dave     

orpheus10 OP
8,668 posts
 

Dave, you really have a beautiful "man cave'; Empire Cartridges were my favorite back in the day, they looked and sounded good.

Did that corner treatment solve all your problems? I'm not sure if I'm up to building one now, are they available for installation?

Without a doubt, you got a swell place for enjoying one of the best rigs I've seen.


I really enjoyed perusing it.
Post removed 
dlcockrum's avatar
dlcockrum
2,190 posts
 
Hi o,

Thanks, but there are some better rigs here on Audiogon, at least more expensive ones. I like to think that my system is an example of how to get superb sound using tried and true older equipment and optimizing the inputs and outputs vs spending huge on the latest equipment without addressing the latter.

I don’t know that you ever solve all of the problems with a pre-built room, but I was fortunate to have been able to start with a dedicated room that was very close to the Golden Ratio by taking out a wall between two 12’ X15’ bedrooms, giving me a 15' wide by 24' long room with a 9' ceiling. I won’t admit to having this in mind when we bought the house, heh, heh. I also found that the "Rule of Thirds" for determining speaker and listening position worked perfectly for my situation.

The acoustical treatments definitely took the mid-bass boom away and the side panels helped a lot with imaging. It is hard to believe how much excess bass waves affect the tonal balance, detail retrieval, soundstaging, and imaging of a good system for the worse.

I also built some floor to ceiling traps of the same design, only half as wide, for the corners behind my listening position but they sucked way to much life out of the sound. I used Shakti Hallographs in those corners instead and am very pleased with the improvement in image specificity.

There are lots of bass traps for sale, but I am not aware of any that actually seal to the corners. They are mucho expensive. You can try, as Jon Risch recommended for a poor man’s solution, to stuff plastic garbage bags with rolls of Owens Corning fiberglass insulation, but I tried that and it was not anywhere close to the traps I built. Ugly as sin too.

Synergistic Research sells a product (Black Box) that they claim tunes the room so that traditional bass traps are unnecessary, but I have no direct experience with it and it is costly ($2K per) and 2 or 3 are needed for a large room like mine.

Billy Bags sells a subwoofer type product that you hang in the upper corner of the room that is claimed to negate standing bass waves. Expensive also .

You gotta either pay to play or be willing to do some work.

Best to you o,
Dave
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