The other night I listened to some music for the first time in a very long while. My equipment is an Ibasso DX300Max Ti, Welborne Labs Reveille passive preamp, DIY Sony Vfet (2SK82 and Bulwark FE) and Frugel-Horn Mk3 with MA Alpair 7.3.
Listening to Amused to Death on In The Flesh Live by Roger Waters the monologue by the old appeared to be coming from way off to my left.
My problem is that with this equipment I have to turn the volume all the way up to get a decent listening volume. I think that the issue is that my preamp has a pair of 100K stepped attenuator. My plan is to replace them with either 25K stepped attenuators, AVCs (Slagle) or TVCs. Right now I am leaning towards the AVCs.
I know that @Zen Mod likes the AVCs.
Listening to Amused to Death on In The Flesh Live by Roger Waters the monologue by the old appeared to be coming from way off to my left.
My problem is that with this equipment I have to turn the volume all the way up to get a decent listening volume. I think that the issue is that my preamp has a pair of 100K stepped attenuator. My plan is to replace them with either 25K stepped attenuators, AVCs (Slagle) or TVCs. Right now I am leaning towards the AVCs.
I know that @Zen Mod likes the AVCs.
question - AVC or TVC, irrelevant , if good
regarding technology, AVC is easier to make properly, than being case with TVC
further- if you don't need galvanic isolation, better to use AVC, from said reasons ....
though, whatever you're using, it must be buffered - if resistive attenuator, then buffer after; if inductive attenuator, buffer in front
and, of course, buffer must be proper
pretty much cheapest and most direct way (these days, if looking around here) is obtaining Iron Pre, then you can build it with resistive attenuator (cheapskate) or saving Cinemags for something and using AVC of choice instead
hard to beat, whatever money involved
regarding technology, AVC is easier to make properly, than being case with TVC
further- if you don't need galvanic isolation, better to use AVC, from said reasons ....
though, whatever you're using, it must be buffered - if resistive attenuator, then buffer after; if inductive attenuator, buffer in front
and, of course, buffer must be proper
pretty much cheapest and most direct way (these days, if looking around here) is obtaining Iron Pre, then you can build it with resistive attenuator (cheapskate) or saving Cinemags for something and using AVC of choice instead
hard to beat, whatever money involved
I am hoping to get a couple of Iron Pre essentials kits. I put my name down too late to get from the first batch. Hopefully they will be available from the shop soon.
Don't think that I need galvanic isolation.
Don't think that I need galvanic isolation.
These arrived yesterday. Now I am waiting on the switches which should ship at the end of this week.
They are Slagle AVCs, I got them from intactaudio.com. The prices are on the website. These are the 28 step AVCs.
Isn't it the other way around, AVC provides a separate floating secondary and TVC is a single tapped coil with shared grounds?
Since I am using a passive preamp there is no gain. I am hoping that by using the AVC instead of 100K attenuators the losses in the preamp will be reduced. My plan is to get a Pre Iron Essential kit when they become available.
Put the AVC at the output if you can.
This solves any impedance issues and cable capacitance changing freq response
The Slagle AVCs are a game changer
This solves any impedance issues and cable capacitance changing freq response
The Slagle AVCs are a game changer
resistive attenuator must have buffer afterwards (at att. output)
inductive attenuator must have buffer at input
explained several times in Iron Pre related threads, same as way to get gain when having AVC, if needed
So if I had an AVC in a separate box I would install it on the out put of the preamp instead of the input like on a resistive volume control? Does it matter if there is another buffer after the AVC like if I was going to convert SE to balanced with XRK's BTSB.
buffering AVC/TVC in front is matter of sources driving that same AVC/TVC
then its Rout is low ....... will you need buffer in front of another stage, not matter of AVC/TVC
ask XRK why buffer is there ...... I'm not familiar with "BTSB"
then its Rout is low ....... will you need buffer in front of another stage, not matter of AVC/TVC
ask XRK why buffer is there ...... I'm not familiar with "BTSB"
crazy idea....!!!! get the smallest variac you can find and use it as a tvc, anyone?
What are the desirable characteristics for the buffer needed before the AVC?
Low output impedance is of course the most obvious characteristic.
High input impedance would be good, but what if all your sources have Zout of 1k ohms or lower?
Is the buffer needed for sinking signal current into the AVC? Is that the issue?
I run a modest Topping D10 DAC and a phono preamp with a 6CG7 mu-follower output into a Niles Audio input selector switchbox, whose output goesto the input on my Intact Audio AVC. The output from the AVC goes straight to a humble Behringer A300 power amp (don't laugh). I haven't noticed anything deficient about the setup. Hmmm.... Maybe I'm missing something?
Low output impedance is of course the most obvious characteristic.
High input impedance would be good, but what if all your sources have Zout of 1k ohms or lower?
Is the buffer needed for sinking signal current into the AVC? Is that the issue?
I run a modest Topping D10 DAC and a phono preamp with a 6CG7 mu-follower output into a Niles Audio input selector switchbox, whose output goesto the input on my Intact Audio AVC. The output from the AVC goes straight to a humble Behringer A300 power amp (don't laugh). I haven't noticed anything deficient about the setup. Hmmm.... Maybe I'm missing something?
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That would actually be an AVC 🙂
I'm planning on experimenting with a smaller variac. From what I gather the materials (especially the core) are important, so it might not be super optimal. Worth a shot though!