Friday, May 22, 2015

Audio Intersections.



I had the fortune to visit a house a few hundred feet from this intersection and thought the names quite fitting for audio.  On this visit I saw a few interesting things the first being this amp.




 That Marantz meter is really telling of the specialness of this particular amp.  This was the prototype for the Marantz model 5.  Another really cool thing was this 7C.



 The collector would probably scoff at the labeling on the back but this was Sid Smith's 7C so I suspect an exception could be made.
  

It also represents a relatively low serial number which adds to its coolness.





Friday, May 15, 2015

Resist!

So Johhny tried some 450 ohm copper resistors under his 75TL's and liked what they did so he asked for some 600 ohm versions for under the RS242 driver.




For the earlier 450 ohm versions I did both inductive and non-inductive wound versions and the non-inductive versions were preferred.  The interesting side effect of the non-inductive winding technique is a  bit of shunt capacitance but since the cathode R is bypassed, I say the more the merrier.


Monday, April 20, 2015

Solder Bars

I was getting a bit low on bar solder for my leaded solder pot so off to the 'bay I went.  The first purchase was 12 pounds of Alpha-Solder.



Unfortunately upon getting it I quickly realized it was lead free with a small 3.5% bonus.


Back to the 'bay for some good old fashioned lead solder and without thinking I bough these.


Now I have a bar of 60-40 and a bar of 55-45 that I don't have the heart to melt down.


Oh well.... To the 'bay batman....


Friday, March 27, 2015

New Toy

I always found it frustrating to be working with an automated limit of ~90Kz from my 192 sound card since the good stuff, particularly with SUT's always seems to happens above 100kHz. 

 

I have seen the Velleman pcsgu250 with its claims of Bode plots to 1mHz for some time and asked about experiences on a number of forums with no response.  I finally sent $150 to newegg last year and procured one.  Flash forward several months and i took some time to rewrite my excel macro's to import the data and I must say I am quite happy with the results.  Sure it is no Audio Precision but it is a million times better than manually entering 100 sets of coordinates per trace on the test bench.

Thursday, March 19, 2015

Name that SRA.






I'd call it close enough to 92 degrees but the sound wasn't the greatest.  It was sounding really good until things abruptly went bad and a quick visual inspection explained the problem.

video

Note to self... hot glue and field coils do not play well together.

Sunday, March 8, 2015

Hudson Valley hiking in March...

.
means hiking *on* the river...






as you know I moved to the Hudson Valley from Memphis before last winter... quite a weather shift... I heard from locals that last year was the coldest they could remember in decades.. "what winters used to be".. or "what winters are supposed to be"... it was cold... well, that was before this year came... we set a record in February - average temperature = 9 degrees Fahrenheit... not average low... average *temperature*.... whew... but you know what?  it is good for working.... and this past Friday when the sun came out, having long eclipsed forty hours in the shop, a few of us took off for a hike in the sun... it was wonderful...

we started off from the house.. hiked down Burget Creek... then onto the Hudson.. all the way down to Catskill Creek... and finally back to the Mill to finish up the day's work...

notice the crazy ice breaks.. the Hudson is tidal... and that makes for some really cool ice breaks...


video








obligatory HiFi Heroin photo:


peace,
me

Friday, February 27, 2015

finally got his 16-A....

... and Elmore James has never sounded better... 


initial placement




it is a Subaru thing




road trip!




yep... pile o' parts



random barn photo




final setup

repro 16a (better bends than any original I have seen)
original WE555's, single Coral tweeter
rebuilt amp (globe 50's), 416's bi-amped


shocking how good this sounds... you just sit there with your mouth agape... 

so much detail.. transients... and then you end up dancing!


*so* much fun....

peace,
me