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Apt Holman Preamplifier Review (vintage Audio)

EJ3

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Just got mine back from restoration by Quirk Audio. Turns out it has the MC circuitry as I suspected. Down the road I may have to play with that but for now the MC sounds (subjectively) glorious. Now where is that Diane Krall album. . Actually I really like her stuff.


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Quirk Audio (Peter) has also taken care of my APT/Holman (this site's review), as well as an ADVENT 300 (this site's review), and my three NAD 2200's (one of which is this site's reviewed)
Audio Proz has parts, such as face plates (there is a high demand for the rack style) and also does work on many things, including that APT/Holman stuff. Vince (owner of Audio Proz & former APT/Holman employee) has also been inside a lot of my equipment. I can only say good things about my experiences with both. One needs to use the repair personnel according to your needs.
 

EJ3

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Do you guys a have a list of modification for the ATP preamp ?
You could go to the website of the companies involved. The mods are not always necessarily static. They continue to evolve. That is a part of why every few years I send my equipment to places to have things done. The 2 that I mention are both on going with me over the years.

If you happen to need an FM alignment done, as far as I now, only Audio Proz (of the 2 places I mentioned) has a lot of experience doing that.

For some things I have different things done by different people for different reasons.
It is likely that mine will not be the same as yours due to requests I have made based on my own experiences, in general and also with whom I am having do the work at that time and their suggestions that I decide to or not to integrate.
We each have our own path to our analog audio Nirvana. Explore & enjoy.
 

EJ3

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Does it take unleaded? Have seatbelts? Here I am with Amir.
Updating the 67 Chevy engine to unleaded is as simple as changing to a modern set of heads (or installing modern valve seats in the old heads). For Pontiacs the whole combustion chamber was Flame hardened prior to the valves being installed so unleaded fuel does not erode the valve seat are of the head to begin with.
As to the choice to use unleaded or alcohol (make way more power and don't need a radiator, has very low emissions but gets crap for fuel efficiency.
Also, have you tried getting any leaded fuels lately? It's not that easy to obtain.
Seatbelts can be installed easily. They are required by most (if not all) racing venues. In fact, way better than the ones required by law in modern cars (a 5 point setup). Seatbelts are a standard procedure for vintage vehicles (although not usually required by the law for street duty).
Apparently you could use hanging out at car shows or going to a vintage track event to show you that these vehicles are generally way safer than your average daily driver.
 

SirPaulGerman

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I found a partial list of upgrades


Do you guy know why he uses that particular op amp for the volume control ?
OPA2134v was chosen, except for the volume IC,which is replaced with a TL207c, given the unique operation of the volume circuit.
 
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