Monday, November 22, 2010

On the Desk: Pioneer SX-1280

So I've had this beast for quite sometime and decided to dust it off and give it a listen. Dirty switches aside, it sounded quite good. Later today the FM tuner just stopped working. Signal meters still function but no sound. I can still listen to anything else plugged in but it's probably best to leave this unplugged this until it's serviced. My heart sank since I know this will be a tricky job. A bad ending to a even worse couple days off.

Here's a web photo I found that shows this off in a better perspective:

This looks like it could be too big of a project for me, and since it's not a total POS, it deserves better attention then I can give it. But you never know.

Video: Nelson Pass at the Burning Amp Festival

This is an interview from 2009 I found at the diyaudio website today. I personally think he is fascinating and that it's great that he supports the diy community. He started on the Junk end of things too when he was young, which snow-balled into a well accomplished career. Check it.

Monday, November 8, 2010

Boston Acoustics A150

Wow, times flying by me way too fast. Lost a whole month due to work and family matters. Anyway I've been sorting through storage and I finally decided to bring these home a give a listen. These speakers have been sitting around unused for years... 

So far, they seem to be working pretty well, but one of the woofers is badly in need of refoam (badly meaning, there is a 2-inch separation on the foam from the basket - I've seen worse). Being that these are supposed to be sealed, then the drivers also must have more excursion to produce the same bass level that a ported enclosure would require. In other-words, while testing, it's best to stay away from gangsta-rap and/or high volumes.

Initial impressions: All-in-all, these are in pretty nice shape considering the age of these. The grills are in great shape, the walnut veneer has some very minor scratches ( I just noticed some slight separation at the corners, no doubt from climate/moisture of the storage facility). With some hesitation, I hooked them up to my amp and fired up the system. For some reason I chose Norah Jones, Come away with Me first. I guess it's because her voice, while I like it, is difficult to tame in my little listening room. I must say she sounded pretty well behaved on track 14 "The Nearness Of You". While I didn't notice the hardness I can get from my Snell CIV's (Which I admit are waaaay to big for the room), I did notice that the intimacy one could get for hearing finer details in her voice wasn't present. I also spun a few tracks of Diana Krall, Quiet Nights. Same sort of impression really. When I tilted A150's slightly back and turned the volume up a bit more, I was able to pick up more inflections in the voice, and also hear a little more depth in Diana's voice, as I should have. However, some hardness returned that I'm oh-so used to, or should I say harshness in the upper ranges of the voice.

Anyway, I didn't plan on getting into a long drawn out review of these speakers, but they are an interesting contrast to the Snell's performance. Contrasting really not that they are so different, but really how much they are relative enough that one could think they were built by the same company (and well, now they actually are- sort of...) Both are a 3 way designs with the same size drivers, 1-4-10. Both utilize paper, similar driver arrangement on the front baffle. The enclosures are different in size, the Snell is most likely 3 times larger and ported vs the Boston's much smaller and sealed enclosure. Nonetheless, both are typical, simple, minimally braced boxes.

The difference? The Snell CIV is by far a more dynamic speaker, able to attack with greater speed on any note, piano, acoustic guitars, strings, symbols, drums -you name it. The Snell can play louder without sounding "Boxy" and allows you to hear more details in every recording. This is not really a big surprise, since the Vifa driver complement is much more advanced in the Snells.

So I say that really, The CIV sounds like a BA-A150 all growed up. BUT....

The Boston is much more forgiving, especially in my small listening room. I'm trying out Steely Dan's - Aja - right now, a CD that has not been remastered and was pretty much unlistenable on the Snell's. Now I'm actually enjoying it. The other thing is that while Bass is not as well defined (well one of the drivers does need repair), I can define more bass "notes" which I imagine is a speaker/room issue + the sealed enclosure. I think these old A150's deserve some attention. Well worth fixing the woofers at least.

UPDATE 11/30/2010:

   I decided to go ahead and re-foam to woofers so I ordered a kit from Midwest Speaker Repair (from ebay though). The ebay offerings suggested that they were in "the know" about the different series and these kits are the only ones that actually looked like they matched in shape. The kit was pretty standard, surrounds, caps, white glue and shims for the voice coil.
    I debated whether or not to remove the dust cap, but I went ahead and did it anyway. Everything cleaned up pretty easily. I would be mindful of letting the glue get a little sticky as suggested before trying to stick the surround on. I did this on the first woofer, but forgot to do it on the second one, which caused me to have to continuously re-align  the surround on the cone as it was a little slippery.
     I have both surrounds drying on the cones as I type this, but I just noticed an issue with the dust caps that seems worth mentioning. They are going to fit just fine, but the old ones were actually pretty air tight, while the new ones are very porous... The material looks very very similar (woven cloth/silk), but the old one appears to have been coated with a light sealant. I tried blowing air through the old one and even ran it under the tap - totally sealed. Too bad I damaged them enough so I can't reuse them. Most likely I'll install them as is for now and contact the company later.

UPDATE 07/28/2011:

   As mentioned before, I did contact the company (this is going back awhile now) about the porous dust cap. They sent along free of charge a different bottle of adhesive that was a bit lighter then the glue used to put the surround on. I used the adhesive to cover the dust cap, which completely sealed it. Once dried, I installed the drivers and used some "Mortite", a clay-like caulking sealant in place of the old dried up gaskets. It comes on a roll and is fairly easy to work with. My concern about this stuff is what it might turn into years from now, however, the roll itself is packaged in a basic cardboard box and is always exposed to air. Even now it is as pliable as the day I bought it 9 months ago.

   Initial listening proved to be promising. The bass has dramatically improved, being more defined then before. I love jazz, and I have had the opportunity to listen to acoustic double bass in several live settings. The A150's allowed me to hear this instrument with greater definition, producing a stable image where ever it was placed in the original recordings. The very bottom notes however, did lack in some detail which is most likely exacerbated by the use of the Jolida 502BRC that I picked up in Feb 2011. The main purpose for buying that integrated was to provide a less fatiguing experience with the Snell CIV's, and I did find that to be very enjoyable - for awhile...
   The trouble with those Snell's is that the dynamic benefits they offer is a double-edged sword. While they have been able to offer a more impact-full experience in dynamic range, they are also too aggressive for extended listening very often. I'm certain it's my modest size man-room. For example, If you were to squeeze a piano, a drum kit and a double bass in a 12 x 12 room and stood in the middle, you would sure enough hear alot of detail, but you would likely run for the hills at full swing. That's the best description I can think of on how the Snell CIV's just don't work in this room, and the small space reflections confuse any hope for good stereo imaging with them. I have Snell JIV's as well, other then being more forgiving, they are just too boomy and unconvincing in any areas. I can safely say that the replacement  JIVdrivers from Snell are merely a close representation of the original, but not an identical replacement and have sonically lost some decent imaging properties that were once possible in this room. With the Boston's however, the story is a completely different one.
   My 16yr old son, without any knowledge on what I was up to, other then listening to music, had plopped down beside me to listen. When he asked-"what speakers are playing", he was referring to the fact that he could hear the music, but wasn't sure if the Snells sitting behind Bostons were hooked up and playing! One cannot ignore immediately appreciable benefits, especially when a pair of loudspeakers can disappear right in front of you, leaving behind only the image and depth of the music itself, and that is exactly what the Boston Acoustic A150's did in this room. It's amazing, I have heard this quality in various systems in the past, mostly from speakers well beyond my reach, but have had a difficult time achieving this kind of performance in my home. Mostly likely this is because A150's were built to function well when placed close to room boundaries. I'm my room, there is limited space for placement that isn't close to the side walls and they cannot be placed way out into the room. The wider baffle design with near-wall consideration, hits the mark in my room, almost as if they were custom made for this specific room.
    The other surprise was that my son also liked the bass better. While I didn't attempt to ask him about why he thought this, I did ponder and listen for awhile to different recordings. It seemed that this same boundary design, along with the shallow roll off of acoustic suspension was able to play deeper, and had what sounded like a much more even response across the entire spectrum.
   Now all this was back when I also had the Denon DAP 2500 preamp and the  PS Audio 200c hooked up. There was still some "Boxiness" to the Bostons and I longed for some the Snell excitement which wasn't associated. While the change to the Jolida did offer up some musical pleasure, I found myself longing again for a non fatiguing music experience.
   With the Jolida, I found that I could enjoy the Snell CIV' more, but the bass was defeatly sloppier and at time had an out-of-phase feeling from the rest of the music. The Bostons had for months sat alone, not connected to anything and I had finally decided to give them another listen.
   As it turns out, the low damping factor seems to compliment the speaker design, as the "boxiness" of the midbass seemed to be missing as before. Vocals also sound more natural and less contrived then before. The rest of the benefits as described previously have remained. I did however have to swap around the front end to re-balance the overall synergy of the system. The Marantz CD5004, which I chose based on cost and the fact that the transport is extremely quiet, worked well going straight into the Jolida 502BRC which drove the Snell CIV's. However when I first swapped to the Boston A150's, the bass was lacking and the top end lacked detail. What I ended up doing was adding a Parasound D/AC 1000, which had previously been removed since it was adding more aggressiveness to the Snell based system that wasn't needed. The DAC added the punch and definition to the new configuration. This was more noticeable then I have noticed before, since I originally had been using the Denon DAP2500 preamp which adds its own gain to the signal from the source. The passive control of the Jolida proved that the Marantz CD player was not up to the task of driving it directly, which while the Snells had become more "forgiving" with the Marantz->Jolida combo, the cost was floppy bass and piano keystrokes that had a blurred quality.
   While this system, (BA,Jolida,Parasound,Marantz) is very enjoyable, some reverberant sounds have less definition and drop off quickly. Also at much louder listening levels, I think individual separation of sounds would stay more coherent if the BA's cabinet was better braced, or should I say just better constructed overall. If I could change 1 thing it would be that. Lastly, i've heard better vocals, sounding more real, but that is typically associated with higher performing loudspeakers at a much higher cost.
   Conclusion: The A150's, a nearly 25 year old speaker, not nearly state of the art even then, shouldn't sound as good as they do. It's been quite a ride and a real learning experience. I have often longed for huge speakers but it's been a very short sided view concerning system, speaker and room synergy. It reminds me that when it comes to performance, being mindful of the end result is more important then any brand, any associated equipment cost...and any bragging rights.


Saturday, September 25, 2010

Dynakit ST-70

Wow.. I didn't know you could actually get this in a new kit form from Dynakit Parts for a mere $675? (without tubes). I think I'm looking a future project here. I've been wanting to build an amp for a long time and it looks like this might fit the bill. Honey, can I have this for Christmas Please?!?

Thursday, September 23, 2010

The Great Internet Migratory Box Of Electronics Junk

Taken from the T.G.I.M.B.O.E.J. wiki page, I ran across this trying to google my own blog. This is being sponsored by Evil Mad Scientist Laboratories . Here's the intro from the wiki:
TGIMBOEJ, The Great Internet Migratory Box Of Electronics Junk is a progressive lending library of electronic components. An internet meme in physical form halfway between P2P zip-archive sharing and a flea market. It arrives full of wonderful (and possibly useless) components, but you will surely find some treasures to keep. You will be inspired look through your own piles, such as they are, and find more mysterious components that clearly need to be donated to the box before it is passed on again.
This looks like a lot of good fun and I have signed up tonight to get a box. I have old PC parts, speaker crossover parts, random ceramic resistors, wire etc I'll be sending along. I'll have to add some pics later as it's just to late at this moment.

Wednesday, September 22, 2010

The Audio Critic

The Audio Critic - Great back issue reads. Start here with Issue #16, 1991 . Lots of letters, Carver and Stereophile in court, a review on the speakers I currently own (Snell CIV) and a funny cartoon page my wife and I swear is just like me - you'll see.

Sunday, September 19, 2010

You Do It Electronics

If you live in southern New England and have never visited this place I suggest you . It's huge - really. Home Audio, Pro Audio, Electronic Test Equipment, Tons of Parts, Educational Kits and on and on. Local to you? Support them! They are even having an event Oct 22/23 to teach soldering basics - wow. (hmm, maybe I should get a new rig so I stop burning myself...)

Saturday, September 18, 2010

Friday, September 17, 2010

Heathkit Oscilloscope O-12


I recently picked this up on a road side sale for $10. I have recapped it and seems to be functioning fine. I'll be adding info to the page as time progresses. Here's the project.