Responses from kalali

Adcom 535L upgrades?
The 535i is a well designed amplifier and responds well to upgrades. Do a search and you'll find a good bit of information about upgrade paths. If I remember correctly it was a Nelson Pass design. Here's one:https://hoppesbrain.com/2015/06/12/the-... 
You may want to try putting diffusers on the front wall behind and between the speakers, if the esthetics are acceptable. Diffusers tend to enlarge the sound space but in some cases might compromise image specificity. Just need to experiment with ... 
Speakers most critical component, , now what fq's are most critical in speakers
I'm not sure if I follow. I may be looking at the wrong Seas drivers but the W18 or W22 are not full range drivers and at 88 dB I wouldn't categorize then as highly efficient. I thought you were talking about high efficiency full range single driv... 
Hiss not Hum help
"Your system has too much gain in the chain."+1. It is most likely the preamp that's adding too much gain. 
Output / Input Voltage Question
What preamp do you have? 1.5V output from a preamp is very unusual. That's even lower than what most (if not all) digital source components provide which is around 2V for single ended outputs. 
Speakers buzzing
Make sure you don't have any chargers for cordless hand tools plugged in the same circuit/outlet as the receiver. The transformers in those devices can interfere with audio equipment.   
Amp pairing questions
From the impedance matching point of view, the amp's 50K Ohm (for SE inputs) input impedance should be fine with Cary's 800 Ohm output impedance (probably @1 KHz). However, most folks using the amp seem to think the balanced connection sounds bett... 
ISO Pucks with Harbeth and Sklyan Stands
I don’t have experience with the Harbeth but I’m using the same stands with my Omega Super Alnico Monitors. Given the weight of the speakers, I picked the ISO-Puck Minis to use between the speakers and the stands and I’m happy with the results. Pa... 
Advice on a budget R2R DAC
I stand corrected. Thanks for the clarification. That's the DAC I have. 
Advice on a budget R2R DAC
misstl, my understanding is Schiit uses the Analog Devices AD5781D/A chip in their Multibit models. I could be wrong, but when I looked at the datasheet for this chip it didn’t seem to be an R2R chip. I have no reason to disagree with Schiit if th... 
Advice on a budget R2R DAC
While Schiit Mutibit DACs are good for the money they are not R2R design. Seokris is a good recommendation. I've heard the 1541 model and I thought it sounded very neutral an engaging. 
Aric Audio Systems Unlimited Preamp
Congratulations, the preamp looks great. I still have my Unlimited that I purchased after starting this thread. Its gone through several incremental upgrades including top grade Audyn coupling capacitors, Mills resistors, ALPS volume/gain control,... 
Entry Level Tube Preamp or Higher Quality Used Model?
Aric Audio Unlimited II.  
Distortion using Node 2i as streamer with Denafrips Pontus Dac
"If you have a Node 2i, why is there even a computer in the chain? Does not compute."Wondering the same thing.... 
Dynamic range - effect on different speaker cables - even very high quality ones
OP, your question was answered in the very first response:"Dynamic range is more likely a function of the recording than the source component. I’m not aware of any commercial recording with DR in excess of 100dB and most commercial recordings don’...