Apt Holman Preamplifier Review (vintage Audio)

[EJ3]

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.


View attachment 222235

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.

 

[SirPaulGerman]

Do you guys a have a list of modification for the ATP preamp ?

 

[EJ3]

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]

Do we know what type of opamps the tested preamp has?

Yes we do. The same part that the factory installed originally. (TL072)

 

[EJ3]

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]

I found a partial list of upgrades

APT Preamp – QuirkAudio

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.

 

[KEM]

As the owner of this I want to mention the Load Capacitive/Resistance Cartridge Termination selection that is on the right of the rear. At the time (and it is still available through some channels, if you need one for one of these, PM me [I do not have them but can put you in touch with someone who had some & can do this the last time I talked to him]) there were available MC cartridge circuits for phono 2 that are customized per order for your particular MC cartridges output. These also had Rack Mount face plates available (which can still be obtained). In fact, this unit had one but I changed it to the household style faceplate.

I am interested. I have a Apt preamp ans preamp 2. I will probably need an MC preamp for my Koetsu RS.
Forgiv my ignorance, but I don't know how to PM in this Forum. Could you help me? Thanks.

 

[EJ3]

I am interested. I have a Apt preamp ans preamp 2. I will probably need an MC preamp for my Koetsu RS.
Forgiv my ignorance, but I don't know how to PM in this Forum. Could you help me? Thanks.

If you move the arrow to the name (under the symbol of the letter their name begins with, the a dropdown opens up through which you can PM.

 

[restorer-john]

If you move the arrow to the name (under the symbol of the letter their name begins with, the a dropdown opens up through which you can PM.

Ah the internet.

Your post led me to link to James Island (my son is James) as I asked myself "where on earth is that?" in SC. Of course I went down a rabbit hole learning about Kościuszko in the revolutionary war and all about his life. Our tallest mountain in Australia is named after him Mt Kościuszko.

 

[EJ3]

Ah the internet.

Your post led me to link to James Island (my son is James) as I asked myself "where on earth is that?" in SC. Of course I went down a rabbit hole learning about Kościuszko in the revolutionary war and all about his life. Our tallest mountain in Australia is named after him Mt Kościuszko.

I have been to the Perth/Freemantle are of your great land. I almost killed myself and others figuring out how to drive on the opposite side of the road. The only right hand drive car that I had driven before was a 1968 Ferrari 365 GTB but I drove it in Charleston & on James Island, the only (minor, due to my being ambidextrous) difficulty was shifting with my left hand. I rather enjoyed the December that I was there, although the locals kept complaining about the "mozi's" being very bad. We have the same problem but we call them "skeeters"), so it was normal to me.

 

[yoyoc]

Last Friday I received an Apt Holman preamplifier from Audioproz with the Level III updates and the 201/202 MC phono card installed and set for my 0.23mV cartridge, and QC check of all the unit's functions and specs per factory service manual. For a while I was interested in purchasing one, but was a bit apprehensive as had read in other web places that this preamp was OK for its time, but was no longer a competitive product.

After receiving the preamplifier and listening to both the MM and the MC phono inputs, as well as a line level input source for 4 days, I am very impressed with the unit's performance. It is very quiet and neutral sounding with great stereo separation of the channels, both MM and MC phono inputs are excellent sounding.

Listening to quality piano and orchestra recordings it produces a nom fatiguing sound that is detailed but not harsh, with abundant and controlled bass where present in the recording. Sounds natural and relaxed.

Sincerely I do not know why some people comment that these are no longer competitive preamplifiers, at least mine, serviced and updated is more than competitive in terms of functions and more important in sound quality.
.

 

[EJ3]

Last Friday I received an Apt Holman preamplifier from Audioproz with the Level III updates and the 201/202 MC phono card installed and set for my 0.23mV cartridge, and QC check of all the unit's functions and specs per factory service manual. For a while I was interested in purchasing one, but was a bit apprehensive as had read in other web places that this preamp was OK for its time, but was no longer a competitive product.

After receiving the preamplifier and listening to both the MM and the MC phono inputs, as well as a line level input source for 4 days, I am very impressed with the unit's performance. It is very quiet and neutral sounding with great stereo separation of the channels, both MM and MC phono inputs are excellent sounding.

Listening to quality piano and orchestra recordings it produces a nom fatiguing sound that is detailed but not harsh, with abundant and controlled bass where present in the recording. Sounds natural and relaxed.

Sincerely I do not know why some people comment that these are no longer competitive preamplifiers, at least mine, serviced and updated is more than competitive in terms of functions and more important in sound quality.
.View attachment 281291

I presume that you have read the review here of one of my 2 APT/Holman Preamps (that are identical) & were resto-modded (no circuit design changes) by Peter @ QuirkAudio. There are also some comments in the comment section by the designer and owner of the company when these were being produced, Tomlinson Holman (whom Peter has current ties with) in the thread (starting at post 145 & continuing for a bit after then some intermittently after that).
Vince Naeve (owner of Audio Proz) has worked for companies such as Apt, H.H. Scott, and KLH. and is also an excellent source for all things related (including parts) to these (and many other products). For those that have not read this review, here is a link to it:

Apt Holman Preamplifier Review (vintage Audio) and also one of my NAD 2200's (resto-modded [with no circuit design changes] by Peter @ QuirkAudio also) reviewed here:​

NAD 2200 Vintage Amplifier Review​

 

[yoyoc]

I presume that you have read the review here of one of my 2 APT/Holman Preamps (that are identical) & were resto-modded (no circuit design changes) by Peter @ QuirkAudio. There are also some comments in the comment section by the designer and owner of the company when these were being produced, Tomlinson Holman (whom Peter has current ties with) in the thread.
Vince Naeve (owner of Audio Proz) has worked for companies such as Apt, H.H. Scott, and KLH. and is also an excellent source for all things related (including parts) to these (and many other products). For those that have not read this review, here is a link to it:

Apt Holman Preamplifier Review (vintage Audio) and also one of my NAD 2200's reviewed here:​

NAD 2200 Vintage Amplifier Review​

Indeed I read them all, also the review at Kenrockwell, some discussion at other forums ( including Steve Hoffman's where there are also some comments aby another gentleman who also worked at the Apt manufacturing who goes by the handle of R. Totale) and read Audio Mag. 1980 review. Also had a lengthy phone conversation with Vince before ordering.

My analog rig consists mainly of a Well Tempered "original square motor" turntable with a Sumiko SHo high output mc and a Well Tempered Amadeus GTA turntable with a Dynavector XX2 low output mc. Both tables have low mechanical noise due to their main bearing and have no ball bearings at the tonearm pivot. Their combination with the Apt Holman is very telling about how low is the noise of the preamp, the quality of their mm and mc phono eq and its neutral sound.

 

[EJ3]

Well, wonderful, another happy customer of some vintage gear that competes well with the better of todays gear.
It is my belief that part of recycling should consist of refurbishing viable gear, generating less waste.
As opposed to being a consumerist, throw away society.
Keepin' the good stuff, which, in many cases is better than the new stuff, after you refurbish it, out of the landfill stream.
Cars, too. can be upgraded to as new or even better (doesn't need to be to todays standards) but like new (or better) can't hurt.
For my 1979 PONTIAC TRANS AM, I converted to a 5 spd manual transmission instead of the 4 spd manual, changed the final gearing, rebuilt the engine so that it met 1981 emissions (without the CAT Convertor) and made 473 HP & got 18-21.7 MPG
(slightly better than my 2012 Lexus ES 350 around town, on the highway, the Lexus beats it with 28 MPG but is much less fun to drive).
If I fuel injected the Pontiac, it would do better on both emissions and economy but that is for the next time it needs rebuilding.
Along with my audio gear, furniture & many other things, my T/A & my 2000 Nissan Frontier are not taking up space in the land fill.
They all just get updated and keep on doing what they were designed to do.
I don't change things just to change them.

 

[yoyoc]

Consumtion is the word for the current times.

I want good sound, balanced, neutral sound, for that I dont casre if it is new or not.

 

[EJ3]

Consumtion is the word for the current times.

I want good sound, balanced, neutral sound, for that I dont casre if it is new or not.

Someone stole the catalytic convertor off of my 2000 Nissan Frontier truck the other day. It was time to install a new timing chain & gears anyway, at 187K miles.
So, I bought a stainless steel exhaust header with a new stainless steel CAT welded to it (which moves the CAT up inside the firewall and causes it to light off much more quickly [and makes it much harder to cut off and steal]).
The exit of the header is 2.5" instead of the 1.75, so I ran 2.5' exhaust and muffler in the stock locations.
While the head was off anyway, I had a machine shop blend the bowls & do minor porting (for better swirl and atomization so the fuel burns more fully, generating more power, better economy & lower emissions)& set the valves correctly.
In addition I changed out the original Fuel Injectors from the original 270 cc 4 injection port ones to 270 cc 12 port ones (for better fuel spray distribution and atomization).
I have just done some general driving for a couple of weeks & the Fuel economy was a bit lower (It typically gets 240 miles to a 14 gal tank full (I tow about 1200LBs. more often than not).
The new parts have broken in (I noticed that the engine had perked up).
So I changed the oil & filter & tested. The emissions were down to 2005 specs, the power (Torque) was up from 150 LB. FT. to 170 LB. FT. and on this tank of fuel it went 265 miles. (normal driving, same as always).
I get to enjoy Less emissions, better power, more fuel economy. for the next 100K miles or so before I have to do any other major work. What's not to like?
In January, I'll likely replace the no longer functional junk factory stereo with something that works. Yee, Hah! Another step better in every way.

 

[rdenney]

It seems to me that this review thread actually validated a properly functioning Apt Holman preamp as a currently viable product, even in the context of distortion thresholds that are far beyond the hearing capability of most people, especially including audio enthusiasts. That validation was done using measurements, which also validate the impressions that people report based on their own uncontrolled testing. Of course, the latter must be validated before it can be used as the basis for advice about what is good. (Anything that actually sounds distorted doesn't need that validation to put it in the do-not-recommend category)

But there are use cases, too. For those of us (including me) who insist on sustaining a phono playback capability, we have a requirement to provide a phono preamp, and we may further require that the phono preamp be integrated with our line preamp. And for those of us (also including me) who maintain playback capability for sources that only have analog outputs, particularly if we sustain support for basically all of those past sources, we require a lot of input switching. And for those of us who want to be able to drive an amp to full power, we require enough line-level amplification to bring those (often) vintage sources up to the current input capabilities of modern amps. After all, the definition of "line level" has never been standardized beyond general industry conventions and norms, and has migrated from 400 mv P-P (the nominal line level output of my open-reel deck) to 1V (prior to the CD era) to 2V (since the CD era). An adjustable preamp is a way to bring all those devices up to the input capabilities of an amp so that on those rare occasions when we need to we can exploit the power that is now available. Passive switching implies amp headroom that cannot be exploited. My own preamp provides switching line amplification so I can be passive at low listening levels but kick in line amplification when needed.

Not all current preamps optimized only for playback from digital sources, particularly streaming sources, fulfill all those requirements. Often, they only support the streaming output from a computer and maybe additionally something like a CD player. Fulfilling those requirements trumps that last 10 or 15 dB of linearity or freedom from distortion, which most people can't hear anyway.

Rick "no minimalist--still defines 'stereo' as 'stack o'stuff'" Denney

 

[yoyoc]

I think in addition...

This pream has a very clean sounding and capable headphone amplifier inside.

As headphone listening has also become common for many people, the Apt Holman seems a good choice as a center for an all around system without having to add several other separate components cables and such related ancillaries.

1 Apt Holman preamp can do a high quality job substituting...

1 line stage stereo preamplifier
1 line stage mono preamplifier
2 phono preamplifiers
1 headphone amplifier
1 18v dc power supply for an additional equipment. I have a DACT phono preamp wich runs on 18v dc, I can hookit up to the Apt and have a 3 phono capable preamp.

I am very satisfied with the sound queality on my updated Apto Holman preamp. Although I can not attest to how it compared to other preamps of the era, I can vouch the the high sound quality of the unit I acquired.

 

[617]

It seems to me that this review thread actually validated a properly functioning Apt Holman preamp as a currently viable product, even in the context of distortion thresholds that are far beyond the hearing capability of most people, especially including audio enthusiasts. That validation was done using measurements, which also validate the impressions that people report based on their own uncontrolled testing. Of course, the latter must be validated before it can be used as the basis for advice about what is good. (Anything that actually sounds distorted doesn't need that validation to put it in the do-not-recommend category)

But there are use cases, too. For those of us (including me) who insist on sustaining a phono playback capability, we have a requirement to provide a phono preamp, and we may further require that the phono preamp be integrated with our line preamp. And for those of us (also including me) who maintain playback capability for sources that only have analog outputs, particularly if we sustain support for basically all of those past sources, we require a lot of input switching. And for those of us who want to be able to drive an amp to full power, we require enough line-level amplification to bring those (often) vintage sources up to the current input capabilities of modern amps. After all, the definition of "line level" has never been standardized beyond general industry conventions and norms, and has migrated from 400 mv P-P (the nominal line level output of my open-reel deck) to 1V (prior to the CD era) to 2V (since the CD era). An adjustable preamp is a way to bring all those devices up to the input capabilities of an amp so that on those rare occasions when we need to we can exploit the power that is now available. Passive switching implies amp headroom that cannot be exploited. My own preamp provides switching line amplification so I can be passive at low listening levels but kick in line amplification when needed.

Not all current preamps optimized only for playback from digital sources, particularly streaming sources, fulfill all those requirements. Often, they only support the streaming output from a computer and maybe additionally something like a CD player. Fulfilling those requirements trumps that last 10 or 15 dB of linearity or freedom from distortion, which most people can't hear anyway.

Rick "no minimalist--still defines 'stereo' as 'stack o'stuff'" Denney

I'm with you on this. Is it that unusual for an audiophile to have or want a streamer, cd player, tape deck and a turntable?

A preamp should be flexible and have lots of functionality with a great interface. Audio performance is secondary, but only because perfection should be almost trivial.

 

[yoyoc]

I'm with you on this. Is it that unusual for an audiophile to have or want a streamer, cd player, tape deck and a turntable?

A preamp should be flexible and have lots of functionality with a great interface. Audio performance is secondary, but only because perfection should be almost trivial.

I would not say that audio quality is secondary, but, that both functionality and audio quality should be expected from a properly designed and constructed product and its reasonable to expect such as a consummer.