The days of on-the-fly tone control is gone. I used to play my preamps as an instrument to enhance passages in songs to personalize my listening experience. If you haven't heard, you cannot know the benefits. I used to have an acoustic room strictly for listening. Ceiling and walls were 12" thick with 5 layers of sound isolation materials. The floor was mounted on pneumatic suspension. Had over 8,000W of amp power divided into a three way active crossover network. Many came for the experience and were blown away; their only comment was "unexplainable". It is impossible to explain how different and lively music can get when equalized on-the-fly as a musical instrument. All the new generation preamps and integrated receivers lack this flexibility. I find myself turning off my audio system shortly after turning it on, for the music is now bla; unlively. I can see all kinds of passages where songs can be improved, but I can't do anything about it. I need to build an audiophile quality preamp with at least base, midrange, treble, and loudness controls. Best would be with a 5 band parametric equalization tone control and a subwoofer output independent from the preamp's full range output. Also, I intend to drive many amps, all in parallel, each individually adjustable to compensate for amp input variations. This preamp will be used in all-stereo mode only. Does anyone know of a good preamp design with high SNR, and very low THD preferably unweighted. This would be a good start.
Hi,
OT on:
If the TO likes to turn tone controls and equalizer knobs so its fine.
Actually I find the critique really off and certainly not helpful.
OT off.
I think You could look at a vintage preamp that features the tone controls You wish for and add as many output buffers You require.
Or copy from vintage amps Datasheets and build a new preamp after Your specs.
Apart from putting an equalizer between Pre and Power amps I don´t know of a all-in-one Preamp that fullfills all Your requirements.
jauu
Calvin
OT on:
If the TO likes to turn tone controls and equalizer knobs so its fine.
Actually I find the critique really off and certainly not helpful.
OT off.
I think You could look at a vintage preamp that features the tone controls You wish for and add as many output buffers You require.
Or copy from vintage amps Datasheets and build a new preamp after Your specs.
Apart from putting an equalizer between Pre and Power amps I don´t know of a all-in-one Preamp that fullfills all Your requirements.
jauu
Calvin
I was once in your shoes and was always tailoring frequency response of every song I listened to, now I find I like my playback systems flat to hear the music how it was intended to be heard.
I was using a Soundcraftsmen CX4100 preamp which has +12/-12db boost/attenuation at 30Hz, 60Hz, 120Hz, 240Hz, 480Hz, 960Hz, 1920Hz, 3840Hz, 7680Hz, and finally 15,360Hz on both channels. I think it is a very nice preamp but I have actually been thinking about listing it on the bay because I haven't used it in years and really don't see myself using it in the future.
I was using a Soundcraftsmen CX4100 preamp which has +12/-12db boost/attenuation at 30Hz, 60Hz, 120Hz, 240Hz, 480Hz, 960Hz, 1920Hz, 3840Hz, 7680Hz, and finally 15,360Hz on both channels. I think it is a very nice preamp but I have actually been thinking about listing it on the bay because I haven't used it in years and really don't see myself using it in the future.
Last edited:
Obviously you are not getting it
I am not looking to equalize the songs/music as for a fixed equalization format; I want to be able to personalize my listening experience. For example, listening to Murrey Head's "Say It Ain't So", I would like to emphasize his voice in specific areas, and his guitar in others. All is done "ON-THE-FLY" at precise times and in very precise slew rates. I need to be able to increase or decrease certain frequencies at times by as much as 12 to 15db for short bursts of high slew rates or by juist a few db for a few seconds with slow slew. Those who have lived the experience can no longer appreciate the same songs/music when listened to in fixed EQ mode. If you haven't had the experience, you cannot understand the difference. Digital EQ is simply not adaptable for this kind of listening. If you are an audiophile purist, you are depriving yourself from the experience. I have met many purists that criticized the practice, but after they have lived the experience, ended up turning away from flat and geared up to relive the experience at will. If you do not know of a good audiophile preamp design with "analogue" EQ controls, I am not looking for criticism on the way I want to listen/play music; I have lost the desire for flat music a long time ago; I rather turn it off for it does nothing for me. I am 63 not afraid of investing stupid money to go back to what I love. So what I want is: Do you know of an audiophile quality "ANALOGUE" preamp design?
I am not looking to equalize the songs/music as for a fixed equalization format; I want to be able to personalize my listening experience. For example, listening to Murrey Head's "Say It Ain't So", I would like to emphasize his voice in specific areas, and his guitar in others. All is done "ON-THE-FLY" at precise times and in very precise slew rates. I need to be able to increase or decrease certain frequencies at times by as much as 12 to 15db for short bursts of high slew rates or by juist a few db for a few seconds with slow slew. Those who have lived the experience can no longer appreciate the same songs/music when listened to in fixed EQ mode. If you haven't had the experience, you cannot understand the difference. Digital EQ is simply not adaptable for this kind of listening. If you are an audiophile purist, you are depriving yourself from the experience. I have met many purists that criticized the practice, but after they have lived the experience, ended up turning away from flat and geared up to relive the experience at will. If you do not know of a good audiophile preamp design with "analogue" EQ controls, I am not looking for criticism on the way I want to listen/play music; I have lost the desire for flat music a long time ago; I rather turn it off for it does nothing for me. I am 63 not afraid of investing stupid money to go back to what I love. So what I want is: Do you know of an audiophile quality "ANALOGUE" preamp design?
The tone control section of Douglas Self precision preamp (1996 ish from memory) is excellent because it has adjustable turnover frequencies (continuously adjustable, not switched).
http://www.diyaudio.com/forums/soli...-built-listened-d-selfs-precision-preamp.html
http://www.diyaudio.com/forums/anal...te-style-eq-design-high-end-tone-control.html
"
Bass [20Hz]
Drum [120Hz]
Lower Voice [500Hz]
Presence [2Khz]
Rasp [5KHz]
Air [20KHz]
"
"
Bass [20Hz]
Drum [120Hz]
Lower Voice [500Hz]
Presence [2Khz]
Rasp [5KHz]
Air [20KHz]
"
I agree with benphysics, flat is usually harsh or brash or thin etc. The recording process is often a crapshoot created by a poorly educated mixer guy. Level changes bring up the issue of a "loudness comp" function, but it's got to be done right (variable). More bass should always sound better, but there's the shroeder frequency room acoustics issue that usually causes boominess, so more bass will often make that worse.
Personally I think it's laughable that high end preamps rarely have tone controls, and if they do the tone functions are meager. I prefer a 4 section Baxandall (variable slope) tone circuit myself. Any less is not enough, and any more becomes a distraction from the listening experience.
I chose to design and build my own preamp just for this reason. See it at my website: Bob's Website
Personally I think it's laughable that high end preamps rarely have tone controls, and if they do the tone functions are meager. I prefer a 4 section Baxandall (variable slope) tone circuit myself. Any less is not enough, and any more becomes a distraction from the listening experience.
I chose to design and build my own preamp just for this reason. See it at my website: Bob's Website
floor suspende on air
Actually the room was virtually maintenance free. The floor was built out of 2x10 joists sandwiched between 5/8 baltic birch plywood and all was glued together. Between joists the floor was filled with insulating materials and the upper part, the part we sit on is carpeted with a 1/2 inch underlayer of felt material. The entire floor was octogonal 16 feet diameter on the corners. It rested on 12 firestone suspension airbags (automotive type) inflated at 20# pressure. I would verify it every 3 months, but never had to readjust in 9 years I owned the home. I then moved from Quebec to British Columbia, in Canada that is. When the music would play in the neighborhood of 115 to 120 db, it was easy to hear a fly sooming around. Actually, it was even disturbing; we had to catch it and throw it out of the room.
Actually the room was virtually maintenance free. The floor was built out of 2x10 joists sandwiched between 5/8 baltic birch plywood and all was glued together. Between joists the floor was filled with insulating materials and the upper part, the part we sit on is carpeted with a 1/2 inch underlayer of felt material. The entire floor was octogonal 16 feet diameter on the corners. It rested on 12 firestone suspension airbags (automotive type) inflated at 20# pressure. I would verify it every 3 months, but never had to readjust in 9 years I owned the home. I then moved from Quebec to British Columbia, in Canada that is. When the music would play in the neighborhood of 115 to 120 db, it was easy to hear a fly sooming around. Actually, it was even disturbing; we had to catch it and throw it out of the room.
Woah...the fly was audible with music playing at 115-120 dB. I'm glad that part is over!
MiniDSP is said to be good for bass management, but not so much for main channel audio listening. Their support forum is also a mess and I will leave it at that. You might want to look into the preamp/DSP/digital crossover from DEQX. That would be worth a listen. Another would be the Accuphase DG-28 DSP that was said to be sonically invisible, and may have had a volume control for preamp duty. Stay away from the Classe crap.
On the other hand, the distributor of Harbeth once said "You should never try to compensate for something a speaker can't do". In light of that, I have yet to see a perfect speaker, recording, or room all in coincidence.
MiniDSP is said to be good for bass management, but not so much for main channel audio listening. Their support forum is also a mess and I will leave it at that. You might want to look into the preamp/DSP/digital crossover from DEQX. That would be worth a listen. Another would be the Accuphase DG-28 DSP that was said to be sonically invisible, and may have had a volume control for preamp duty. Stay away from the Classe crap.
On the other hand, the distributor of Harbeth once said "You should never try to compensate for something a speaker can't do". In light of that, I have yet to see a perfect speaker, recording, or room all in coincidence.
Last edited:
Hey Bob you are my kind of guy. We are definitely on the same page. I went onto your site and saw your preamp. This is what I want to build; something in the same range with preferably 5 bands (enhanced parametricly variable) including a sub control crossed in the vicinity of 125hz as a bi-amp network. I don't know if you ever heard of an audio decompressor. I made one in the early 70s. I made it differential amplitude variable. When music were recorded onto vinyls, (mind you they still are), the physical size of the groove was too narrow to reproduce the full spectrum of the signal. Therefore, during the recording process the signal was compressed: this means that the lower amplitudes were increased while the higher ones were decreased. The decompressor was a little trickier to reverse the process. therefore I made it differential amplitude variable. In my room, I would reach the same effects as if the band was live inside the room, but we would be inside all speakers facing us. Quite a treat. Hey keep me informed if you decide to revamp that preamp of yours with state of the art components.
Stay in touch,
Ben
Hi Ben,
I like your thinking. The "loudness control" is an interesting area. To my mind far and away the best one I have seen is in an old "Journal of Audio Engineering Society" mag from the 70's. It was good, very clever and cheap to DIY. It was interesting because the designers built it with a variable "break point" for the bass reinforcement. I.e. as the volume decreased the point at which the extra bass increased moved up the frequency scale. (Or more correctly, the point at which the lower mids were depressed moved up in frequency....)
From memory each channel involved only one op-amp and a handful of passive components, the final result was within plus or minus 3db of the Fletcher/Munson (if I've spelt it correctly) curves over a 50 plus db range, all controlled through one linear pot that carried no DC current.
Now I can't put my hands on my copy at the moment. If you're near a Uni you might chase it up. But I can recall that it was NOT an item listed on the cover (sorry) which will make it harder to find but was down the back in the "Engineering briefs" section I think. If you do physical search you will need to check the index....
I'll have a look at my "archives" and see if I can get a more precise reference, date Vol. No. etc......then you can but a copy from them for a small fee even if not you're a Audio Society member.
Cheers,
Jonathan
I like your thinking. The "loudness control" is an interesting area. To my mind far and away the best one I have seen is in an old "Journal of Audio Engineering Society" mag from the 70's. It was good, very clever and cheap to DIY. It was interesting because the designers built it with a variable "break point" for the bass reinforcement. I.e. as the volume decreased the point at which the extra bass increased moved up the frequency scale. (Or more correctly, the point at which the lower mids were depressed moved up in frequency....)
From memory each channel involved only one op-amp and a handful of passive components, the final result was within plus or minus 3db of the Fletcher/Munson (if I've spelt it correctly) curves over a 50 plus db range, all controlled through one linear pot that carried no DC current.
Now I can't put my hands on my copy at the moment. If you're near a Uni you might chase it up. But I can recall that it was NOT an item listed on the cover (sorry) which will make it harder to find but was down the back in the "Engineering briefs" section I think. If you do physical search you will need to check the index....
I'll have a look at my "archives" and see if I can get a more precise reference, date Vol. No. etc......then you can but a copy from them for a small fee even if not you're a Audio Society member.
Cheers,
Jonathan
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.