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Let me try to sum this up,
Wyred 4 Sound STP-SE preamp
Balanced output from that into Merrill Audio Taranis amp
Unbalanced RCA output from same preamp to Anthony Gallo Reference SA subwoofer amp
Just a question it is not as in my face with the sub bass as compared to an active preamp same configuration. Have the sub amp set at max + 6db , volume levels at max on the sub amp.
Can anything be done about this or is it just a sound that I should get used to because it is a difference between passive versus active preamplification?
Edits: 06/30/17Follow Ups:
I read the manual and I think I know what the problem is ... your Wyred STP SE preamp is an active preamp ... it has a power cord .. a transformer .. a diode bridge and power supply caps ... this makes it an active preamp ... Wyred misleading calls it passive because it has "no additional gain' ... it should actually have been referred to as an active preamp with unity (zero) gain ... your Wyred is not a true passive preamp ... it just does not provide any additional gain added to the source's signal
In a true passive preamp it is the source that is driving the signal and the extra set of ICs at the output of the passive preamp to the amp through the passive preamp's volume control and why when you said "Passive Preamp" members assumed that the source was doing the driving and not the Wyred preamp ... because they thought as you indicated it was a passive preamp ... but it's not
Because you said "Passive" some members felt it was a true "Passive Preamp" and lacked the drive to push/drive the signal from the source through the Wyred's volume control and out the second set of IC's at the preamp output to the amp ... but that is not the case
The Wyred is an active preamp that has the ability and takes complete responsibility of driving the output ICs and can do so because it has a power supply and is active ... it just doesn't provide any additional gain from the source's signal and none is needed
Most modern system have enough gain from the source to drive the amps and no additional gain is needed but the preamp does provide the needed current to drive the second set of ICs at the output after the volume control
So far so good it's working as intended ... but I think I know what your problem is .. bear with me
The Wyred preamp is also "Buffered" meaning that the XLR outs do not see the impedance that the RCAs outs are connected to ... that's very good and a excellent feature
In a un-buffered preamp when you hook up an XLR out and a RCA out at the same time ... the preamp sees the input impedance of both devices (amps) that the XLR and RCAs are connected to and actually interprets the combined input impedances of both load devices ... amps ... as half of what they actually are ... lets say both your main amp and sub amp have a input impedance of 50K ohms each ... a un-buffered preamp will read that as 25k ohms ... not good because it's low-ish
That's an outstanding preamp as it is active with no gain and buffered so each output ...XLR and RCA only sees the particular load (amp) that they are connected to instead a of summing the input impedance loads of both amps
So what's the problem and how do you fix it
Some how you turned on the home theater by pass circuit which is truly passive and meant as a pass through only for HT configurations
I told you I read the manual ... how to fix
The very first thing is to turn the volume way down on the sub amp so you don't blow the subwoofer after you correct the HT bi pass .. then following the specific instruction below for turning the HT bi pass on ... reverse it and turn the HT bi pass off
Again ... TURN THE SUB AMP VOLUME DOWN FIRST ... and then turn the HT bi pass off ... if you can't figure it out ... Call Wyred ... I'm sure they can walk you through it
From the Wyred manual
To properly set up the HT-Bypass feature you must complete the following. Make sure the unit is powered up, but in the off position. Press in and hold the input up and down buttons while simultaneously pressing the power button (volume knob). The display should come on in the setup menu. Press input up or down until you find a screen that says "HT Bypass". Once "HT Bypass" is selected, push the MUTE button. This will select the HT Bypass mode, and allow for assignment. Now rotate the volume knob to turn HT Bypass on and select the input desired for this operation. ((NOTE: Make sure you select the correct input in the set-up. If the input is incorrect, and a signal is applied to that input when selected, the source will be playing VERY LOUD.)) Now press the power button again to exit the set-up menu.
You can access the selected HT Bypass input any time by pressing the HT button on the remote, by scrolling through the inputs on the front of the unit or on the remote, and also by using the remote trigger input. Using the remote trigger input will automatically configure the preamp for use with an HT system, and also power up connected amplifiers via the trigger outputs.
Thank you very much. I was very confused about the HT setting when reading the manual, I have no intentions of using a home theater setting, perhaps it was set by default at the factory or I was inhebriated one day and I turned it on. I just set it to off.
Sound illness has now been cured, thank you very much for your help.
Now go enjoy your new toy and tell us all about it when you're done.
That sounds like one serious designed preamp.
Redemptions is a tremendous motivator ... I got involved in this thread when I felt something was being missed ... I started by reading the manual and realizing that B/H's Wyred was an active not passive preamp and that contributors were treating it as a passive with passive downsides as B/H used the wording of "Passive"
Reading the manual you will come to realize that Wyred poorly used the word "Passive" to actually mean no additional active gain ... can't blame everyone for being confused including B/H because of Wyred's misleading language
All active preamps are Class A with no negative feed back but Wyred took it much further ... they realized that someone may want to use both outputs at the same time and buffered them ... also they realized most modern systems have to much gain anyway and didn't need any additional gain so they made the preamp a "unity gain" type offering no additional gain in the preamp ...this allows the volume control to be turned up higher with less resistance in the circuit and improves transparency .. dynamics and headroom
B/H's STP SE pre comes with Wyred's stage one improvements ... from their site
Stage 1 Upgrade
Our available Stage 1 STP-SE upgrade features our discrete proprietary regulators along with 24 Vishay Z-Foil resistors, four premium inductors, four Schottkey diodes and an upgraded fuse. These enhancements which focus on the power supply and input/output buffer circuits present greater fidelity and definition.
If you noticed in my second post I said the biggest choke point in most preamps is the volume control pot ... well take a look at Wyred's stage 2 upgrade ... from their site
Stage 2 Upgrade
The Stage 2 upgrade, includes all of the above plus an upgraded IEC inlet, 48 Vishay Z-Foil resistors located in the resistor ladder volume control, 16 upgraded high frequency filter capacitors and a green OLED display. Direct attention to the signal path throughout the volume control and filtering circuit yields major enhancements to an already exceptional product.
"48 Vishay Z-Foil resistors located in the resistor ladder volume control"
Yes ... Redemption is a tremendous motivator
if you mean being cleared of sin, I have blessed you.
just remember when it is time to go, move away from the light, most people go towards the light, and they wind up back here.
All active preamps are Class A with no negative feed back...
Those which use op amps are most certainly not as they employ large quantities of NFB for linear operation.
I stand corrected ... sometimes I tend to paint the picture with to broad a stroke ... I should have said most premium preamp are class A with no negative feedback
I would not own a active preamp ... I built a very simple volume control based on Slagle Autoformers .. also I wouldn't own a Dac or 1 box Cd player with op amps in the analogue output either ...
My Arye D1ex has a class A no negative feedback Jfet based output
My experience with op amps in the CD/Dac output is under high current demand they can't keep up with the current called for and go into oscillation trying to keep the input and output in balance ... my belief is the brief oscillation creates a temporary distortion that is very short lived and presents itself as a screaming or shout-ness by the performer's at their peaks
Just my subjective observation ... I struggled with this shout-ness and screaming on the peaks with a number of player for a number of year s ... always blamed it on room acoustic issues that I couldn't seem to tame then I bought the Ayre ... problem solved
Maybe it's just me or the way I roll but I wouldn't use an active preamp (to much gain ) or a Player/Dac that employed op amps regardless of how high the quality of the op amps were including discrete type ... this works for me and I'm very happy not chasing all he screaming female performer's
To each his own but I do stand corrected on my "all" preamp rant
That a nice preamp ... unity gain means it doesn't boost the incoming source signal any ... this allows you to turn the volume control up higher ... the higher up the volume control position the less resistance is used in the circuit to attenuate the incoming source signal ... the more transparent the sound will be
Biggest choke point in most preamps is usually the volume control ...especially at lower volume settings
Plus with the XLR and RCA outs being buffered from each other ... there is no communications between them and the preamp can see the true individual input impedance of the amps optimizing the signal transfer
What's for supper ... ;-)
when only it is connected? That might be hard to judge, but you should be able to tell if there is a large difference. Completely disconnect the main amp, play sub alone. If you think it's loud enough by itself, you may need to reduce the gain of your power amp or increase its input impedance.
Or you can connect the power amp single-ended, which will reduce level by 6db. That could be done with a simple balanced/SE adapter or by altering the balanced IC's to run SE.
berate is 8 and benign is 9
From what I'm reading you are saying the sub isn't loud enough?
If the signal is coming from a passive - you don't have enough signal.
Does you preamp and amp have RCA inputs available? Is so try the setup with the RCA cabling and see if the preamp has enough signal to get as loud to suit your needs.
My main amp only has balanced input. The sub amp only has unbalanced RCA input. The pre has balanced XLR and unbalanced RCA out . XLR out to amp, and RCA out to sub amp is the current configuration.
There is bass, just not as incredible as when I was using an active preamp.
I think you just answered you own question. You NEED the gain of the active preamp. Or at least the sub does. You could run a line to the active preamp FOR the sub. But now you're really making things complicated. And in audios setups - that never ends well.
You are loosing too much signal in the balanced input circuitry. The terms passive and balance are some what a contradiction in terminology and ideas.
Got it, thank you very much for helping me understand.
It may also be frequency roll-off if it's a true passive w/o a buffered output. The combo of passive output impedance, capacitance of interconnect cables, and input impedance of the sub could be rolling off freq extremes. Just a thought.
If that's true then again, he needs the active preamp to act as a buffer and gain stage.
I'm a little fuzzy on the balance connection. Isn't the signal slit at the source and then rejoined at terminus? Shouldn't there be a simple buffer stage in that circuit? And how could that all be passive?
As I understand it, this is a buffered passive preamp which has a 6db gain stage that kicks in when needed. Personally I don't like the term "buffered passive preamp". A better description would be an active preamp with unity gain.
I married the perfect woman. The downside is everything that goes wrong is my fault.
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