MORTIS
Alien Member
As some of you may recall, I had a C712 for about 3 years and I enjoyed it immensely. You may also recall that I will only own a preamp that allows a certain amount of control over the frequency spectrum; or in other words, a preamp with equalization controls and preferably more than just a bass and treble, primarily because I never play anything without these controls in the circuit. The C712 was the first preamp I’ve owned with a loudness that was variable, and I was quite pleased to discover that using the bass and treble in combination with the variable loudness actually allowed the 712 to be very flexible of the musical presentation. With those 3 controls I could pretty much dial in any kind of sound I wanted; from a crisp and clean ‘in your face’ presentation, rather like the musicians are performing directly in front of you, most of which could be achieved by simply leaving the EQ controls out of the circuit. Or I could get a very warm and smooth presentation that extended the performance beyond the wall behind the system, much like what some folks might describe as a classic tube sound, which is the sound I prefer but without the tubes. I like it warm and deep with a recessed soundstage along with a fat woody timbre of acoustic bass instrument, somewhat the way the big old vintage drivers could sound but with the added speed and accuracy of modern speakers.
For quite some time now I’ve been trying to decide between a C48 or a secondary/back-up system such as an MA7000 in case my current pre and power were ever out for a period of time in need of service. Through research I was never able to determine whether the preamp and EQ sections of the C48 and MA7000 were of the same quality. There are of course some technical differences such as the MA7000’s volume/balance and EQ pots being all analogue (I think), whereas these pots are digitally controlled in the C48, not to mention the C48 has Mac’s first EQ section to use 125hz and 2000hz bands instead of 150hz and !500hz as used in all previous 5 band EQ’s. Supposedly the newer selections are more useful frequencies.
I ended up deciding to choose a dedicated SS preamp with McIntosh’s latest technology within a model segment, and so I picked up this C48 about 2 weeks ago and have been slowly tweaking it to my taste.
It Arrives! now for the obligatory jumping banana
I could call this a review of the C48 but for many readers it would be considered rather specific due to my limited use of the features within the C48. I have not yet tried the built-in DAC because I’m instead using what I figure must be a higher end, quad balanced DAC in the D100, so no comments of the USB either. Nor am I using the MC phono section and will rarely ever use the MM, which as yet I’ve not even tried. I’ve got a ton of vinyl but most is well used from decades ago during my years as a full-time nightclub DJ. Only a small percentage of it do I care to listen to anymore while relaxing in my music room. I don’t do HT so forget Pass-through or any related benefits.
No folks – I’m interested only with the C48’s abilities as purely a preamp along with McIntosh’s exclusive 5 band EQ. For me, that much desired EQ being the main reason between choosing the C48 or MA7000.
My time with the C48 has been rather interesting, with a couple of unexpected bonuses of which I will discuss later on.
Before hooking the C48 into my system, I wanted first to have one good listen to the C712 in order to make the best of my ‘audio memory’. Unfortunately my memory had to wait up to 2 hours for me to pull the components out of the system and then I had to modify the wall-unit a bit to fit the C48 with the other pieces.
I knew I’d have to start my session with the C48 with the EQ bands at top dead center and out of the circuit until I could begin adjusting them to my taste, which I also did with the C712 during my final listen in order to begin the comparison on an equal plane. Having owned the C712 for about 3 year and using it a few hours almost every day, in all my time with it I’ve listened to it flat (EQ out of the circuit) for probably a total of 2 hours, and about 1.5 hours of that was during my final listen before switching to the C48, therefore my evaluation of both preamps played flat can be considered quite limited and possibly inadequate.
With that said, I was not aware of any differences between the 2 preamps while played flat. Considering there is about 15 years difference of age and technical advancement, there must surely be some sonic differences, but I didn’t hear it, and I consider my system and speakers to be very revealing.
Understandably at this point I’m feeling a little nervous about having spent several large $ on a preamp and so far no perceived benefits. Optimistically however I slowly begin adjusting the frequencies until the music starts to sound the way I prefer.
As I said, the C712 is very flexible in its tonal presentation but with the Bass control bending half the range and the treble bending the other half and the VL bending the whole thing, it requires you to carefully learn their curves and how each effects the whole, which for me can be a tedious and delicate process taking up to several listening sessions to precisely dial in. I say ‘delicate’ because the EQ controls on the 712 are, in my experience, extremely sensitive to the slightest movement. Depending on the recording, I would often have to make an adjustment of a control no more than 0.5 minutes on the dial in order to get it just right. Outrageously sensitive perhaps, but few visitors to my music room would notice the change.
The C48 on the other hand seems less sensitive to changes and is much easier to zero in on a specific range covered by a selected frequency. Within a comparatively short time I was able to get the sound much closer to the way I like, and I've been fine tuning it a bit every couple of days since. I want to get a baseline that will be used most of the time from which I may make slight adjustment depending on the recording; so to make it easier to return to that baseline, I’ve attached tiny segments of green Frog tape at those baseline set-points.
At this point you’re probably thinking ‘Damn It man – get to your conclusions of the sound and sonic performance!!’ Ok ok, here we go… .
My initial thought after I got a preferred tonal presentation was that the C48 seemed to sound more ‘digital’ than the 712, but after a while and a few tweaks, I realized I was hearing faster transient attacks and finer detail, and greater precision in the lower octaves, and yet it still sounded very natural and smooth. The presence of singers and musicians sounded more real with more clearly defined space and distance between band members.
I also noticed with a couple of hot recordings, such as when the recording medium seems to be pushed to the max in saturation while multiple instruments are all playing full tilt and loud, the C48 managed to better maintain the same composure as when a small ensemble is playing at moderate levels, with a lack of any distortion or graininess or smudging of the stage separation and instrument purity. This may be due in part to the C48 having a line level input sensitivity of 0.45v as opposed to the C712’s sensitivity of 0.25v. If so, then it’s a smart change considering the typical output of 2.0v from many disc players and DACs which can overdrive some older preamps that have higher sensitivity inputs.
For quite some time now I’ve been trying to decide between a C48 or a secondary/back-up system such as an MA7000 in case my current pre and power were ever out for a period of time in need of service. Through research I was never able to determine whether the preamp and EQ sections of the C48 and MA7000 were of the same quality. There are of course some technical differences such as the MA7000’s volume/balance and EQ pots being all analogue (I think), whereas these pots are digitally controlled in the C48, not to mention the C48 has Mac’s first EQ section to use 125hz and 2000hz bands instead of 150hz and !500hz as used in all previous 5 band EQ’s. Supposedly the newer selections are more useful frequencies.
I ended up deciding to choose a dedicated SS preamp with McIntosh’s latest technology within a model segment, and so I picked up this C48 about 2 weeks ago and have been slowly tweaking it to my taste.
It Arrives! now for the obligatory jumping banana
I could call this a review of the C48 but for many readers it would be considered rather specific due to my limited use of the features within the C48. I have not yet tried the built-in DAC because I’m instead using what I figure must be a higher end, quad balanced DAC in the D100, so no comments of the USB either. Nor am I using the MC phono section and will rarely ever use the MM, which as yet I’ve not even tried. I’ve got a ton of vinyl but most is well used from decades ago during my years as a full-time nightclub DJ. Only a small percentage of it do I care to listen to anymore while relaxing in my music room. I don’t do HT so forget Pass-through or any related benefits.
No folks – I’m interested only with the C48’s abilities as purely a preamp along with McIntosh’s exclusive 5 band EQ. For me, that much desired EQ being the main reason between choosing the C48 or MA7000.
My time with the C48 has been rather interesting, with a couple of unexpected bonuses of which I will discuss later on.
Before hooking the C48 into my system, I wanted first to have one good listen to the C712 in order to make the best of my ‘audio memory’. Unfortunately my memory had to wait up to 2 hours for me to pull the components out of the system and then I had to modify the wall-unit a bit to fit the C48 with the other pieces.
I knew I’d have to start my session with the C48 with the EQ bands at top dead center and out of the circuit until I could begin adjusting them to my taste, which I also did with the C712 during my final listen in order to begin the comparison on an equal plane. Having owned the C712 for about 3 year and using it a few hours almost every day, in all my time with it I’ve listened to it flat (EQ out of the circuit) for probably a total of 2 hours, and about 1.5 hours of that was during my final listen before switching to the C48, therefore my evaluation of both preamps played flat can be considered quite limited and possibly inadequate.
With that said, I was not aware of any differences between the 2 preamps while played flat. Considering there is about 15 years difference of age and technical advancement, there must surely be some sonic differences, but I didn’t hear it, and I consider my system and speakers to be very revealing.
Understandably at this point I’m feeling a little nervous about having spent several large $ on a preamp and so far no perceived benefits. Optimistically however I slowly begin adjusting the frequencies until the music starts to sound the way I prefer.
As I said, the C712 is very flexible in its tonal presentation but with the Bass control bending half the range and the treble bending the other half and the VL bending the whole thing, it requires you to carefully learn their curves and how each effects the whole, which for me can be a tedious and delicate process taking up to several listening sessions to precisely dial in. I say ‘delicate’ because the EQ controls on the 712 are, in my experience, extremely sensitive to the slightest movement. Depending on the recording, I would often have to make an adjustment of a control no more than 0.5 minutes on the dial in order to get it just right. Outrageously sensitive perhaps, but few visitors to my music room would notice the change.
The C48 on the other hand seems less sensitive to changes and is much easier to zero in on a specific range covered by a selected frequency. Within a comparatively short time I was able to get the sound much closer to the way I like, and I've been fine tuning it a bit every couple of days since. I want to get a baseline that will be used most of the time from which I may make slight adjustment depending on the recording; so to make it easier to return to that baseline, I’ve attached tiny segments of green Frog tape at those baseline set-points.
At this point you’re probably thinking ‘Damn It man – get to your conclusions of the sound and sonic performance!!’ Ok ok, here we go… .
My initial thought after I got a preferred tonal presentation was that the C48 seemed to sound more ‘digital’ than the 712, but after a while and a few tweaks, I realized I was hearing faster transient attacks and finer detail, and greater precision in the lower octaves, and yet it still sounded very natural and smooth. The presence of singers and musicians sounded more real with more clearly defined space and distance between band members.
I also noticed with a couple of hot recordings, such as when the recording medium seems to be pushed to the max in saturation while multiple instruments are all playing full tilt and loud, the C48 managed to better maintain the same composure as when a small ensemble is playing at moderate levels, with a lack of any distortion or graininess or smudging of the stage separation and instrument purity. This may be due in part to the C48 having a line level input sensitivity of 0.45v as opposed to the C712’s sensitivity of 0.25v. If so, then it’s a smart change considering the typical output of 2.0v from many disc players and DACs which can overdrive some older preamps that have higher sensitivity inputs.
