Can I build my own LOUDNESS control with minimal sound quality degradation? (1 Viewer)

[Chris PC]

I often listen to my system without the subwoofer, trying to use my front speakers -3 dB point of 32 hz. I often feel as though I'm missing some of the bass impact which I had in my older system. My old system had sealed speakers with a -3dB point of 45hz and a 50 watt per channel amp with a loudness control on my new receiver. It really bugs me that not only does my new receiver not have a loudness control, but I also have no bass and treble in source direct. Now with my newer setup, I have ported speakers with similar, if not less distored bass down to 28 hz or so in room, but a steeper drop off there and no loudness control. Forgive me for throwing even more processing into the mix but I am desparately nostalgic of loudness controls. I like music at medium to loud levels, but often, I don't like having to turn up the entire volume because I want more bass. I love full bass sound and I notice that when I turn up the volume I reach a point where the bass seems full in comparison and then I turn it up higher and it seems as thought the midrange and treble gain more than the bass does. I imagine my 105 watt x 3 receiver has its limits into 6 ohms, but I feel cheated sometimes. Often I will hear smooth low bass, while other times I feel I am lacking that full warm bottom end bass levels.

On the web I have seen plans and schematics for loudness controls and they interest me. Is there anything out there that would be decent enough to use? Frankly, I never noticed the difference in sound quality when I defeated the tone controls on my older amp. I want a loudness control!

 

[Wayne A. Pflughaupt]

Chris,



Loudness controls were never intended to be used like you have been using them. They were designed to boost the lows and (to a lesser extent) the highs at low volume , to compensate for the ear’s natural reduction in sensitivity at the ends of the frequency spectrum at reduced listening levels. To that end, loudness controls gradually reduced the effect the higher the volume was turned up. Unfortunately too many people used them at normal and high listening levels to induce some “boom/sizzle” to their sound.



Loudness compensation controls typically never worked very well because the receiver manufacturer had no way to know the efficiency of the end user’s speakers. The only decent loudness control anyone ever had was Yamaha’s variable control that allowed the user to induce the exact amount his speaker’s needed.



At the risk of sounding simplistic, why not just turn on the sub or use your tone controls? Or connect a 10-band EQ between the CD player and receiver? Any of these would give you a lot more control of your system’s bass. Makes a more sense than a cobbled-together “boom/sizzle” switch, IMO, and it will eliminate the "sound degradation" issue.



Regards,

Wayne A. Pflughaupt

 

[Philip Hamm]

You're dissapointed that receivers don't have bass and treble controls when in "tone direct" mode. That's the whole point of a "tone direct mode"! That's the reason they exist, to bypass that stuff. So turn off tone direct and turn your bass up to compensate for your speakers. I have an all analog system in my office with a Harman/Kardon HK3270 analog stereo receiver and a pair of old Mirage 290i speakers with no sub and I crank up the bass for just the same reason you do.

 

[Chris PC]

receivers don't have bass and treble controls when in "tone direct" mode. That's the whole point of a "tone direct mode"!

No equipment I have seen mentions "tone direct". All equipment simply mentions Source Direct or Direct and even some of those allow tone control use, such as the Outlaw 950.
I guess I find the fault is in my receiver. My old integrated amp had a source direct button but the bass, treble and loudness could still be used, if you wanted. I tried and tried to compare but I could not hear a difference in sound quality with and without the tone controls (leaving them flat). I listened many times just to see if the tone control circuits degraded the signal, but I could never hear anything.
The problem with my system now is that the receiver has a source direct mode which both cuts out the subwoofer and dis-allows any tone controls. There are many integrated amps, receivers and pre-pros which allow tone control when using direct modes.
The reason I use the direct mode is because my receiver cuts off the beginning split second of CD tracks when I use a digital connection so I have to use an "analog" connection from my CD player. That means if I don't use source direct, I've got DA in the CD and then AD and DA again in the receiver before the signal is finally amplified. Even if I liked the sound of the regular mode, I have to turn my subwoofer on and off. Really, I just want to hear what my main speakers are capable of and higher bass at medium to lower volumes is what I want.
I'm ultimately going to upgrade to another receiver or pre-pro and I hope to be able to at least turn up the bass using the direct mode. The Outlaw 950 allows it and I am considering that route. The newer NAD's T752 and T762 are also options and I hope they also allow tweaking of the bass
Thanks for the ideas guys. I may still try a circuit for fun if its cheap, but ultimately I'll try to stick to simplicity and a working tone control

 

[Wayne A. Pflughaupt]

Chris,

My old integrated amp had a source direct button but the bass, treble and loudness could still be used, if you wanted.

This is very peculiar. The whole purpose of a “Source Direct” setting is a minimalist path that gets the signal from the CD player to the amplifiers with the least amount of superfluous circuitry. If this integrated amp left the tone controls intact, you have to wonder, exactly what was the “Source Direct” mode eliminating from the signal path...??

Since your receiver is having problems with digital feeds, why not just loose the digital connection all together? Then you wouldn’t’ have to use the “Source Direct” setting and thus retain use of your tone controls

Regards,

Wayne A. Pflughaupt

 

[Chris PC]

Yes but as I mentioned, if i don't use source direct, I would then be left with D to A in CD player and then A to D and D to A in receiver again. Pretty sure thats how it works because when playing CD player via analog inputs, the DSP's, dolby pro logic, tone controls and bass management all work, which leads me to believe there is some A to D and D to A going on. The point of using a digital connection would be limiting myself to only one D to A conversion in the receiver before amplifying and that would make SOURCE DIRECT not such a big deal and not necessarily desirable. There are other reasons I'm not super fond of my receiver so I am looking for an alternative. As I've mentioned, the Outlaw 950 allows tone control on the analog direct mode and may not require my using it since the 950 may not cut of the digital signals.

 

[Saurav]

Source Direct and Tone Bypass are two different concepts. The first eliminates the A-D and D-A conversions on analog inputs and all the processing done in the digital domain, like bass management. The second eliminates the extra resistors and capacitors in the signal path due to tone and balance controls.

 

[Philip Hamm]

Source Direct and Tone Bypass are two different concepts. The first eliminates the A-D and D-A conversions on analog inputs and all the processing done in the digital domain, like bass management. The second eliminates the extra resistors and capacitors in the signal path due to tone and balance controls.

SO it appears that the equipment with "source direct" mode that you've been using in the past have had the EQ implemmented int he analog domain, and now your receiver has the EQ implemented in the digital domain. This would explain the difference.

 

[Chris PC]

Yes. Exactly. I don't want to get into the other problems but lets just say my receiver is quirky. I remember playing the subwoofer only with my main speakers disconnected and increasing the bass only to watch the Radio Shack SPL meter register a -1/2 dB each time I increased the bass 1 dB while playing tones between 20 and 50 hz. I tried this with my regular front speakers and they produced a 1 dB increase in bass. Weird. My main problems with the Marantz SR6200 are the 100 hz crossover and the digital dropouts.