Help with identifying some caps and their values on a phono preamp

[peranders]

About the glued parts in Grado amp, I think that this arrangement has nothing to do with "audiophileness" rather than keeping the caps in particular in place because of the thin wires.

[peranders]

Originally posted by Peter Daniel
I kind of miss that site, with production pics: http://www.connoisseurdefinitions.com/

Is the site down? I also like production pictures.

About the Grado amp: It's soldered by hand! Even a series of 100 per year or at the time pays if it's machine soldered. It's not advantage at all to solder by hand! It just takes time, and cost money and the quality gets uneven.

Mention one good thing!

[Werner]

Originally posted by Fred Dieckmann
This is a $500 product

...

BTW I don't think that is the complete schematic from the circuit description on
the website.

Counting the resistors, I think it is.

Rather disappointing when you come from reading things like

"the most successful solution to one of the most complex technical challenges in the field of audio that Grado Labs has ever tackled"

"We realized immediately that a challenge like this was not going to be met by using either of the time-honored methods of passive or active equalization circuits."

"The processing problem has been split into two separate parts: a forward propagating signal current and a back propagating error voltage. "

So I take it that most of that high $500 price is there to cover the cost of a truly inventive copywriter.

Now if we confront that copywriter with one of Jonathan's creations we might be in for some interesting proza :-)
\

[peranders]

You know, you can rewrite just about anything on order to get it sound interesting. It's called marketing.

Note also that the error voltage isn't propagating at all. You have it in one point!

Werner, if the copywriter can produce so much of so little how would he feel if he wrote about any high end product?

[Fred Dieckmann]

"Mention one good thing!"

The fact that you are in Sweden and not endangering American lives comes to mind........

Hand soldering is better than wave soldering. You can use decent silver bearing solder instead of the often contaminated and usually questionable solder in a wave soldering machine, about 200 lbs of it in the last one I looked at. It shouldn't be that hard for a simple design that's not a parts farm..... I bet that Grado can find some decent people to solder thier stuff. They have been building phono cartridges for many years and that must require some skilled labor. I can pick the phone and find Mil-Spec trained people to hand solder in about an hour around Dallas.

Marketing Hype........... what can I say? It is about the norm in High End audio. And this is very mild as it goes. I read it about three times and the light went on above my head. If you have a clue as to what they are talking about, you can probably figure out a very short list of what op amps they picked from to use and realize the circuit description is pretty accurate. I can hardly wait to Email Mr. Carr so we can both laugh at everyone that missed the real big clue in the description of the circuit topology. This same basic approach has been used by others. The CJ Premier Three tube preamp comes to mind. I'll bet John Curl will take about 30 seconds to figure it out as well. Please don't stop with your commentary though, many of us enjoy it, honestly.

[jcarr]

Peter, Per:

>I kind of miss that site, with production pics:<

Interestingly, I have received other comments to the same effect. One problem is that the 3.0 has been phased out of production, and even the prototype shown was not necessarily representative of what the production units were like. And the relative lack of information about our current products on our new website is another problem. We should restructure our website so that there is sufficient information on all of our designs, albeit with clear distinctions between past and present products.

But it requires time to take new photos, write up-to-date text, oversee the layout etc. Time spent on the website is time that cannot be used to work on products.

>About the Grado amp: It's soldered by hand! Even a series of 100 per year or at the time pays if it's machine soldered. It's not advantage at all to solder by hand! It just takes time, and cost money and the quality gets uneven.<

Agreed. Machine assembly is faster, more consistent, and in the end, cheaper than hand work (unless the pick-and-place operator gets the component reels mixed up ). OTOH, a trained craftsmans' hand is far more flexible than a machine, and allows the designer to implement board and physical structures that would be impossible on a machine. There is a proper place for both, I believe.

Using unskilled labor to form simple component leads and solder basic joints doesn't make sense, unless the cost of local labor is so dirt-cheap that doing the assembly entirely by hand turns out to be the cheapest available option. But this implies that the local wage standards and hence the local standards of living are both quite low. The choice would depend on the country and locale that you operate in.

regards, jonathan carr

[SY]

Fred: Why does the Grado ad copy make me think of that funky phono stage that Fulton used to market? (showing my age again) That was a current-sensitive box, a real oddball.

[peranders]

Originally posted by Fred Dieckmann
"Mention one good thing!"

The fact that you are in Sweden and not endangering American lives comes to mind........

Hand soldering is better than wave soldering. You can use decent silver bearing solder instead of the often contaminated and usually questionable solder in a wave soldering machine, about 200 lbs of it in the last one I looked at.

The tin gets contaminated but this means not that hand soldering is an alternative, besides I and Jonathan talk about SMD soldering at the main part and then you have no problem with contamination.

If you are a production manager and have to choose between 20 people (with not too high wages) and a pick-and-place machine plus an oven, the choice is easy.

Judging by the photos, their personel don't reach any MIL standard as far as I can see.

I have nothing against hand soldering but it isn't better than machine soldering if we talk total quality...and .. using normal parts.

[Fred Dieckmann]

Wave soldering not the process used to solder SMT but through hole like the board under discussion. A lot of contaminants get in wave soldering machines. I have worked about ten years with through hole and 3 years with SMT manufacturing.

We are not talking about large scale production for an item like the Grado preamp. There is a large amount of hand wiring that is not possible to automate.

I and others have made our case for specialty solders so I can state again that there are specialty solders and some manufactures use them and feel they are audibly better than the standard tin lead solders generally used.

There are plenty of contract assembly houses here with very qualified labor.
I worked with an ex Texas Instruments guy a few years ago who ran such a shop. Several of his employees were retired assembly workers from TI that were Mil-Spec trained.

It is not always advantageous to run pick and place. If there are enough non auto insertable parts, a separate step for auto insertion is not really time saving. Small quantity runs as often happen with products with products like these and don't justify the set up and debug time for auto insertion. Add frequent redesign and part changes typical in audio design and you compound the problems.

Every automated component placement and soldering line has an inspection and rework step in the process to catch machine and process problems. Even Million dollar SMT lines. I have been there at 7 in the morning to for beta runs of SMT boards more times than I remember. We had to have the manufacturing process perfect in order to release the board to assembly houses have the country and half the world away. We had about a million boards a year and design for manufacturing was critical.

I done hand assembly for my own specialty audio products and design for very high volume SMT products. Forgive me if have my own views developed over about a decade and a half of being involved hands on with the manufacture of PCB assemblies.

I am impressed by your ability to judge soldering quality from a compressed digital picture. I my last job we used microscopes.

[Peter Daniel]

It takes about 5 min to put this board together and with small scale production run I don't see any serious reason for automation here.

It's probably much harder to attach all the wires than make the board.