My girlfriend has a very high quiet squeaky voice that is hard to hear. And she talks a lot. My system at her place sounds like crap at the low volumes required to have a conversation, but totally awesome at 100db+. Wondering if there is a decent tube line stage circuit including loudness compensation? Loudness and tone controls seem to be the antithesis of decent audio, but my system only sounds good at one volume without it. Ideas or suggestions? Headphones are out, I would never get any again....
There is a misconception about both loudness compensation and tonecontrols.
Loudness compensation is a mechanism that compensates for the ears sensitivity for different frequency's is volume dependent. At low volumes ( which at music listening is below the volume where the music would be heard in real life) highs and especially lows are reduced in sensitivity. Adjusting the amps relative levels will restore the natural sound. As volume is increased the loudness compensation are reduced and at "natural level" it totally gone.
Some better amps has a way to adjust the level where loudness takes effect ( braun comes to my mind), other amps has a switch to enable or disable loudness.
As for tone controls, most people tends to need to adjust tone balance now and then. Some ( deniers) resort to tube rolling or speaker adjustments or even advanced external parametric equalizers.
Reason for this urge is deficiencys in the recordings, room problems or speaker/amp deficiency's.
A well designed tonecontrol will be "off" at some well-defined setting ( be out-of-cirquit). But all tonecontrols need an extra amplification stage, this might be the reason amps lacking tonecontrols sometimes sounds better. A few amps has a "loop" where an external tonecontrol may be connected and activated at the flick of a switch thus keeping a win-win strategy where one can totally bypass tonecontrol circuits when wanted and engage when wanted.
My 5c on the subject, and it is of cource my subjective opinion.
@bobgroger
The loudness compensation circuitry found in "vintage" tube equipment, like the Scott 299D, requires a tapped stereo (ganged) control. AFAIK, "the only game in town" for a tapped control is a 250 Kohm Noble brand part from Michael Percy.
Perhaps the best solution to your problem is a 2 or more bands per channel parametric equalizer located in the tape monitor loop of a design you already favor.
The loudness compensation circuitry found in "vintage" tube equipment, like the Scott 299D, requires a tapped stereo (ganged) control. AFAIK, "the only game in town" for a tapped control is a 250 Kohm Noble brand part from Michael Percy.
Perhaps the best solution to your problem is a 2 or more bands per channel parametric equalizer located in the tape monitor loop of a design you already favor.
If you can live with 100K then this unit from Radio Shack is the answer.
Needs to be configured for your circuit and expectations.
RadioShack 100KΩ Dual-Ganged Stereo Audio Potentiometer
Needs to be configured for your circuit and expectations.
RadioShack 100KΩ Dual-Ganged Stereo Audio Potentiometer
While that part is an excellent find, it seems to be constructed in a manner (not sealed) that will require periodic cleaning/lubrication. Also, the type of wiper used will lead to a comparatively short service life. IMO, it is unrealistic to expect the spring loaded, machined, carbon block found in PEC KKA series controls. BTW, the 100 Kohm value is a plus for avoiding adverse interactions with the Miller capacitance of triodes, like those found in the 12AX7/ECC83.
Given the low price of the "Rat Shack" item, purchasing 2 pieces makes sense to me. Prepare for possible "early" failure.
the Shack is back?
there is plenty of ways to do loudness with separate pot, no need to use tapped volume pot
actually, variable loudness is lot more useful, kind of independent of the speaker sensitivity issue
there were many threads about it, I cant seems to find the one i remember...
Loudness experiences?
there is plenty of ways to do loudness with separate pot, no need to use tapped volume pot
actually, variable loudness is lot more useful, kind of independent of the speaker sensitivity issue
there were many threads about it, I cant seems to find the one i remember...
Loudness experiences?
the guy who started the thread obviously did not bother to search
this one has passive loudness meant to be placed after the preamp, before the amp
quite useful, some tried it, I did not yet, but was about to
Loudness stage
this one has passive loudness meant to be placed after the preamp, before the amp
quite useful, some tried it, I did not yet, but was about to
Loudness stage
Honestly there are none. She is great. Just hard to hear. We recently reconnected after 40 years apart. We are playing teenagers again. 
@bobgroger
This write up about your Parasound SS preamp indicates that it does not have a traditional tape monitor loop. Still, the Rec jacks allow you to use the device for source selection into a DIY built tube preamp that has the Fletcher-Munson loudness circuitry your situation suggests is necessary.
Please post a photo of the P/LD-1100's back panel, so the members can see what the jack set looks like. What signal level drives your power amplifier(s) to full O/P?
This write up about your Parasound SS preamp indicates that it does not have a traditional tape monitor loop. Still, the Rec jacks allow you to use the device for source selection into a DIY built tube preamp that has the Fletcher-Munson loudness circuitry your situation suggests is necessary.
Please post a photo of the P/LD-1100's back panel, so the members can see what the jack set looks like. What signal level drives your power amplifier(s) to full O/P?
I had the same concern, but used several for periods from 5 to 17 years in a school environment and had no trouble.
The problem with voice may be "old man" decline of hearing. The description is classic and I see the age is plausible.
Between age and lack of knowledge, I can't tell if the P/LD-1100 (schematic uploaded) can simultaneously drive the Rec O/Ps from 1 of the enumerated I/Ps, while feeding the volume control from the Direct I/Ps. I do see that the Rec O/Ps are driven by buffers, which would support "parallel" operation. Field engineering changes (FECs) to support "parallel" operation, if not already present, might be feasible. Those members with expertise are asked to post.
The idea is to select a source and feed it, via the Rec jacks, to some DIY tubed circuitry that will process the signal according to the OP's desires. The processed signal would be fed into the Direct jacks and, eventually, the power amplifier(s). The DIY project would contain a defeat switch, which bypasses the signal processing circuitry, for those times the OP wishes to listen at an "ordinary" level.
The idea is to select a source and feed it, via the Rec jacks, to some DIY tubed circuitry that will process the signal according to the OP's desires. The processed signal would be fed into the Direct jacks and, eventually, the power amplifier(s). The DIY project would contain a defeat switch, which bypasses the signal processing circuitry, for those times the OP wishes to listen at an "ordinary" level.
