^ Reported... I am not sure.
It's been quite some time, but I have very, very casually listened to the SE, Balanced with SE input to SE output, Balanced with SE input to Balanced output, and Balanced with Balanced input to Balanced output. SE was set to 6dB gain. Pots were all the same. With that said, the SE build had the Edcor transformers, and the balanced had Jensen. Sooooooo..... a truckload of salt vs. a grain...
I didn't / don't have any way to check everything properly, but I did ensure output level from my amplifier was the same (at the time a commercial amplifier was used). Why... because it is truly differential throughout (at the time... it was the only one I had) and very low distortion (compared to all my DIY amps). Source was a commercial DAC (same reasons as above) using Qobuz streaming through a reasonable (to me) streamer. This was a few years ago.
tl;dr - It was a bit of a challenge, but not too hard to level/channel-match the Balanced each time b/c I used dual pots. I thought the balanced was a better match for my system, and I love the versatility of the balanced.
In some non-back-to-back tests and just trying to remember over time... I use balanced in to SE out all the time when I don't have an amp with XLR in. Conversely, the SE in to balanced out is wonderful! I've got an old CD player that I love, and it only has RCA output. The analog output stage of that thing has a 'sound' I prefer that doesn't stick with it when I run digital out to my DAC.
With every source that has SE outputs, I don't recall hearing a difference between using the SE in to SE out of the balanced to the SE iron Pre.,,,but I think that's a good thing, right?
With any source that has a balance output I prefer using the balanced Iron Pre outputting into balanced amplifier(s). Note... it could easily the that the amps are better too... b/c ... monoblocks. My DAC to Iron Pre to Amp is my chain 99% of the time, and I'm not using monoblocks 99% of the time. Most of my DIY amps have a distortion profile that would likely overtake any differences in the pre-amps.
In situations of non-differential/balanced amplifiers etc. etc.... I just don't know. I'd toss a coin in the air and say that ... if you're never planning to use a differential/balanced amplifier... or one with a differential input stage (AJ) or don't have any sources with differential/balanced output ... then SE is the way to go. It's easier... cheaper... and to me... there would be no difference in the sound (in normal situations).
Still... you don't need me to nudge you. Build both.
Note... all of this.. could easily ... easily be confirmation bias and/or bad memory. I have both, and I use the balanced. That's the only thing that's reliable.
It's been quite some time, but I have very, very casually listened to the SE, Balanced with SE input to SE output, Balanced with SE input to Balanced output, and Balanced with Balanced input to Balanced output. SE was set to 6dB gain. Pots were all the same. With that said, the SE build had the Edcor transformers, and the balanced had Jensen. Sooooooo..... a truckload of salt vs. a grain...
I didn't / don't have any way to check everything properly, but I did ensure output level from my amplifier was the same (at the time a commercial amplifier was used). Why... because it is truly differential throughout (at the time... it was the only one I had) and very low distortion (compared to all my DIY amps). Source was a commercial DAC (same reasons as above) using Qobuz streaming through a reasonable (to me) streamer. This was a few years ago.
tl;dr - It was a bit of a challenge, but not too hard to level/channel-match the Balanced each time b/c I used dual pots. I thought the balanced was a better match for my system, and I love the versatility of the balanced.
In some non-back-to-back tests and just trying to remember over time... I use balanced in to SE out all the time when I don't have an amp with XLR in. Conversely, the SE in to balanced out is wonderful! I've got an old CD player that I love, and it only has RCA output. The analog output stage of that thing has a 'sound' I prefer that doesn't stick with it when I run digital out to my DAC.
With every source that has SE outputs, I don't recall hearing a difference between using the SE in to SE out of the balanced to the SE iron Pre.,,,but I think that's a good thing, right?
With any source that has a balance output I prefer using the balanced Iron Pre outputting into balanced amplifier(s). Note... it could easily the that the amps are better too... b/c ... monoblocks. My DAC to Iron Pre to Amp is my chain 99% of the time, and I'm not using monoblocks 99% of the time. Most of my DIY amps have a distortion profile that would likely overtake any differences in the pre-amps.
In situations of non-differential/balanced amplifiers etc. etc.... I just don't know. I'd toss a coin in the air and say that ... if you're never planning to use a differential/balanced amplifier... or one with a differential input stage (AJ) or don't have any sources with differential/balanced output ... then SE is the way to go. It's easier... cheaper... and to me... there would be no difference in the sound (in normal situations).
Still... you don't need me to nudge you. Build both.
Note... all of this.. could easily ... easily be confirmation bias and/or bad memory. I have both, and I use the balanced. That's the only thing that's reliable.
As to a remote volume shaft, I have used several of the kits from Partsconnexion. They say 10 mm, but it is long enough to go through the 10 mm faceplate with enough threads to get the nut on the back.Sneak preview 🎥
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There's not really too much to say about this build, things are extremely straightforward, it works great, and as the other builders already know, it sounds absolutely fantastic!
A few notes before people ask -
I didn't use a remote volume shaft as I didn't have one. Use one of you want, it's a great idea. The wires from PCB to the volume pot are mic cable, and it's wonderfully quiet.
I used a fused and switched IEC. It makes the wiring so much simpler.
In North American wiring convention black is Live (as that's what color it will turn your finger if you touch it), white is Neutral, green is Earth/Ground. Please note the heat shrink on the IEC, and also that the IEC has L and N labeled. (hard to see in these photos).
Live is sent to the front panel switch (which is AC rated, of course) and then to the lead windings of the transformer primary, which being an Antek happen to be red. The trail winding of the primary attaches directly to neutral. These winding leads are unfortunately black, but oh well.
Safety Earth/Ground is bolted directly to chassis through the green wire.
If it's not immediately obvious, the grey wire is connected from the pad on the PCB marked "Chassis" to the chassis earth.
The power on/off LED steals power from the pads on the PCB, and has an inline resistor under the heatshrink. I used a blue, and about 33K as modern LED are amazingly bright.
Cable from the PCB to Volume is Canare L-282AT https://www.redco.com/Canare-L-2B2AT.html
The little PCB on the Alps volume pot isn't necessary, but it sure does make things easy to solder.
The rest of the signal wiring is Mogami 2330 https://www.redco.com/Mogami-W2330.html
No idea where I got the knobs... probably Amazon, I had a bunch in my box and these looked pretty cool.
Russellc
^ Reported... I am not sure.
It's been quite some time, but I have very, very casually listened to the SE, Balanced with SE input to SE output, Balanced with SE input to Balanced output, and Balanced with Balanced input to Balanced output. SE was set to 6dB gain. Pots were all the same. With that said, the SE build had the Edcor transformers, and the balanced had Jensen. Sooooooo..... a truckload of salt vs. a grain...
With every source that has SE outputs, I don't recall hearing a difference between using the SE in to SE out of the balanced to the SE iron Pre.,,,but I think that's a good thing, right?
Still... you don't need me to nudge you. Build both.
Note... all of this.. could easily ... easily be confirmation bias and/or bad memory. I have both, and I use the balanced. That's the only thing that's reliable.![]()
My reason to build the BAL after SE is up and running in my system is that I like the sound of the SE and my DAC has BAL-out. Then I get more signal out of the source which I see as a technical advantage. The DAC is advertised having 2 x ESS chips. Since they emphasize this I assume 1 x ESS could do it for a stereo setup and using two makes it possible to make the DAC "true" balanced.
Next as I use mono block power amps I got the strange idea to built IP-BAL as mono blocks and then utilize that the XLR connection is better or long distance than RCA.
A question I have not asked but have had in my mind for some time:
How well does the IP handle full line signal (e.g. 2.1 Vpp for SE and 4.2 Vpp for BAL)?
What is the limit where amp is still giving quality output?
rails for buffers are +/-15V
so, say that buffers will cruise more than happily all the way to 20Vpp of input signal
which is 7.07Vrms
and that again amplified with autoformer gain
re. sound of SE compared with sound of Bal
both are singing more than good enough ......... while in any system certainly having lesser own character than driven amp
so, let's take one of possible scenarios:
you'll be equally happy driving Aleph J with either IPre SE or IPre Bal
which one you'll use - strictly dictated with sources at hand
so, say that buffers will cruise more than happily all the way to 20Vpp of input signal
which is 7.07Vrms
and that again amplified with autoformer gain
re. sound of SE compared with sound of Bal
both are singing more than good enough ......... while in any system certainly having lesser own character than driven amp
so, let's take one of possible scenarios:
you'll be equally happy driving Aleph J with either IPre SE or IPre Bal
which one you'll use - strictly dictated with sources at hand
Yes, ok.....voltage gain using Iron has an advantage that it will not clip easily.
My BAL build (XLR in, RCA out). I will need this configuration:
"RCA out taken from XLR out, pins 1 & 2
1 GND
2 Positive hot"
Now another stupid question......which I think I can answer myself......but maybe there was a "comment" to it......
From GND to Positive hot there is half voltage swing than from Negative hot to Positive hot.
If I should utilize the larger voltage swing from N-hot to P-hot for an RCA connection to power amp would have required that Iron was coupled with galvanic isolation so N-hot could be used as an "artificial" Gnd for the power amp?
Maybe I will be put into "prison" asking such a question........
My BAL build (XLR in, RCA out). I will need this configuration:
"RCA out taken from XLR out, pins 1 & 2
1 GND
2 Positive hot"
Now another stupid question......which I think I can answer myself......but maybe there was a "comment" to it......
From GND to Positive hot there is half voltage swing than from Negative hot to Positive hot.
If I should utilize the larger voltage swing from N-hot to P-hot for an RCA connection to power amp would have required that Iron was coupled with galvanic isolation so N-hot could be used as an "artificial" Gnd for the power amp?
Maybe I will be put into "prison" asking such a question........
well, in SE context, it's hard to go without proper GND potential ....
all "problems" are obviously born from fact that ppl are taking follower amps for granted
function vise, those are "just" half amps - so - if existing gain stage preceding your follower amp isn't on par with your (voltage) demands - either put interstage xformer*** in between, or build adequate gain stage*** for in between
simple as that
*** and you can solve both gain and interfacing tasks
all "problems" are obviously born from fact that ppl are taking follower amps for granted
function vise, those are "just" half amps - so - if existing gain stage preceding your follower amp isn't on par with your (voltage) demands - either put interstage xformer*** in between, or build adequate gain stage*** for in between
simple as that
*** and you can solve both gain and interfacing tasks
With IP-SE I have just gain enough at 6 dB setting. So with low level recorded classical music I use close to full gain from DAC (digital vol. control close to max.).
So I will be fine with just 6 dB gain. I guess I will end up with same absolute voltage out from IP-SE (6 dB setting) vs. IP-BAL (using RCA out (only utilizing half voltage swing)) even that DAC has 2 x Vpp out at XLR-out (compared to RCA-out).
So I will be fine with just 6 dB gain. I guess I will end up with same absolute voltage out from IP-SE (6 dB setting) vs. IP-BAL (using RCA out (only utilizing half voltage swing)) even that DAC has 2 x Vpp out at XLR-out (compared to RCA-out).
Well, all is prepared
Hi Robin,
Did you build or buy that muses looking volume control?
Thanks
To quote mvaldes.."@Robin De Wolf you have C5 &C6 in the wrong position."
One pin of the film cap has to be mounted through the hole all the way on the left..
One pin of the film cap has to be mounted through the hole all the way on the left..
Attachments
Thank you very much!@Robin De Wolf you have C4 & C5 in the wrong position.
This is Muses V1 by Meldano, he has a thread here on the forum. I had two stereo volume control sets which I have combined now for this buffer.Hi Robin,
Did you build or buy that muses looking volume control?
Thanks
I'm very careful to not present positions where choices are leading to trouble
that cap position is pretty much self explanatory, if brain is present
even if not, any possible ookup will result in zero problems - cap simply will not be in circuit and it's function being far from critical

that cap position is pretty much self explanatory, if brain is present
even if not, any possible ookup will result in zero problems - cap simply will not be in circuit and it's function being far from critical

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