Intact Audio

No on grounding the - of a balanced signal. Does the unit have the LL 1764 on it? that can be configured for SE output. As for the input that gets a little more interesting... How is the input currently handled? It looks like you could simply use 1/2 of the entire circuit SE so that may be what is b...

Hey,

The schematics are of a balanced input / output circuit. How do you plan on using it SE?

Do you have a schematic of the active board?

dave

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well it took a year but I finally got the transformers done for this circuit and they work as expected. (apologies for the cell phone screen grabs... I am out of my element when it comes to working on a PC). Here is the spice simulation of the circuit that I started with. IMG_8203.jpeg This is the m...

I do not think it is fair to comment on inductive volume controls as a whole since there are many design considerations and your best approach is to measure and listen to the specific case to determine suitability. In speaking about my autoformers, they do really well driving difficult loads but ult...

Hey, you answered all of your questions and the load the TVC will see is not 600Ω since the secondary is left open. The primary inductance will appear in parallel with the reflected load but at anything below unity that value will get very large since it will be multiplied by the turn ratio squared....

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Hello Merv, I will answer your questions inline below. 1. Ideally I would have liked to have both 8 and 4 ohm speaker outs as well as a headphone jack but after reading around, having more secondary outputs may not sound as good as sticking to one output? If this is the case then I'll stick with an ...

There are a couple of things going on here. When you terminate the "stock" LCR with both 600Ω and an inductance as is happening in this thread, the source Z driving it must also be 600Ω or things shift. The attached picture shows a stock tango driven from 150Ω (green) and 600Ω (blue) when ...

Taken out of context of the entire paper, it is unclear what docali is referring to in this statement. For a correct filter response both sides of the t-network must be "terminated" with 600 ohms In the amplitude realm if the output is terminated with 600Ω, a change from a input terminatio...

replies.. 1) I don't have a picture handy but the 28 step is simply the 14 step with pins on both sides. It is no more or less difficult to solder but keeping track of the wires becomes the main issue. 3) the prewired modules have 3dB steps at the beginning and end and 2dB steps in the middle. dave

You are indeed correct that the panels are driven by step-up transformers from the plates of the tubes. It always made little sense to me to step down the voltage 25X for a cable run to only step it up 270X to drive the panels. Asking two transformers to do this (amp output / quad input) and maintai...

If you consider the basics, the LCR has its irregularities in the middle of the audio band where transformers are flat so the two should not effect each other. Granted the Transformers will have bandwidth limiting issues but that is independent of the type of EQ used. I guess I am trying to say is t...

I'm getting 1000 new accounts created a day and several of them were making spam posts so I shut down all new activations. If you want to join, send me an email and i'll get you set up with an account.

dave

When you start getting into higher impedance cartridges and SUT's the miller capacitance (and cable capacitance) of the input of your phono becomes an important consideration. In addition to the simple filter you speak of, the additional capacitance pushes the LC resonance down in frequency and depe...

Didn't have much time to ponder things since I already had a solution in hand.... Ditch the L-pad on the 2441 and replace it with an autoformer. Here is the big picture of the change showing the Lpad being replaced with an autoformer and the frequency domain plots clearly overlap. Screen Shot 2021-0...

People go on and on about damping factor and I continue to be astounded how they only consider the ratio of the output impedance of the amp to the input impedance of the "speaker". In truth the load presented by the "speaker" is actually the impedance of the crossover and everyon...

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WE300B, I think the important factor here is to either drive the LCR with its characteristic impedance OR load it with its characteristic impedance and not both. If you choose to drive it with its characteristic Z then the output can (should) be left unterminated and if you load it with its internal...

The attached picture is from the wiring the $200 autoformer FAQ . It is only for 14 positon s but it isn't hart to imagine another 14 taps. To add another input just use a 3 posiiton selector and wire another sent of RCAs. For parallel output simply wire in a second set of RCA's to the output. dave ...

The LCR network either needs to be driven by its characteristic impedance or loaded at its characteristic impedance. In either case you have a situation where Rsource=Rload which causes a 6dB loss of amplitude so there is really no difference in gain either way you go about it. This all started when...

everything looks right. the only concern is the inductance of the primary might be a bit low. worth a try though.

dave

I'll answer these question sin line. -what will be the ideal output impedance of the phono stage output(to go into the autoformers preamp)? The lower the better and typically under say 3kΩ but I have had people go as high as 6-8k and report great results. -what will be the ideal output impedance of...

If you don't close the network with 600 ohm the Z is higher respect the original diagram. Would you please measure this so you can realize that you are incorrect. If you consider a 600Ω LCR as a three terminal "black box" with in, out and ground, it has an 600Ω input AND output impedanc...

In the last schematic the EQ600 is not terminated with 600 ohm so load seen by input stage is higher this entire branch of the discussion was in response to your quoted text above. I believe the quoted text to be incorrect which is why I asked you to simply measure the input Z of the EQ-600 with 60...