Have Passive Preamps Finally Come of Age?
@georgehifi I agree with your assessment of impedance mismatch between the Hattor passive (unbuffered) preamp and the choices of amplifiers that tweak1 selected. @tweak1 You initiated this thread discussing passive preamps, yet you have nearly changed everything downstream to accommodate it (that is, the Hattor passive unbuffered preamp). This includes a new amp, a different set of speakers and ditching your powered subs. I respectfully disagree with your assessment that a simple gain switch will rectify the impedance mismatch George referred to. Just for kicks, why not obtain his suggested amp to audition? You’ve changed so much already; one more audition won’t be much work. And don’t be afraid to liberate yourself from the need of a class D amp, unless you are worried about electric bills. There are a lot of good design topologies that will likely bring smiles to your face when mated into your system. Trying is the pudding of life. And I know you at least enjoy trying new gear! Just my two cents!! Enjoy the music!! |
@tweak1 why do you think that class D amplifiers are the way to go here? It seems that your bias is that class D represents the SOTA. Is that your position here? And why do you believe an amplifier’s inherent power output potential is too much power for a speaker of a given efficiency? And what is the actual impedance input of your amp that results from flipping it to a higher dB output? |
@tweak1 there you go again with the snarky remarks. I’m not going to post anymore Q’s to you. I’ll just make two statements to suggest you are deceiving yourself with your equipment choices and rebuttal remarks to others. First, a 600 ohm increase in input impedance (3.5% overall) by increasing your amp gain will not restore anything magical to your setup. It’s still an impedance-mismatch for the Hattor. Second, there is no such thing as an amplifier being overpowered for any set of speakers. Period. Musical transient peak demands typically can require 100’s of watts to the speakers. I doubt your class D amp of 125W RMS is up to muster. Over. And. Out. |
About designers/manufacturers nixing the website content of other designers/manufacturers, there is a lot of puffery to go around. To wit, take the following quote about the specifications of an attenuator from an Australian website: “Frequency response: 0hz – to almost Infinity. (Lightspeed) (interconnects are the determining factor here)” Notwithstanding the hilarious frequency response claim, I’m pretty sure the internal wiring to and from the internal portions of the RCA input and output jacks of the attenuator is likely going to be more bandwidth limiting than any external RCA interconnect(s). Reminds me of glass house owners being stone throwers. |
@georgehifi I think you protest a bit too much. It is you that continues to get off topic, most recently with your negative comment (or three) about another equipment designer/manufacturer’s website content. You then get all defensive when I point out another website having inaccurate content about its product specifications. (I did say “hilarious” in my post, which you opted to take as being a serious comment other than for what it is.) If one stays on topic and perhaps one won’t generate additional commentary. |
This back and forth is hilarious. Let us distill it to its simplest form. 1. atmosphere considers George’s Lightspeed unit to be a fine passive preamp device, albeit limited in its design (1 input and 1 output) and clearly not as good as what atmosphere has auditioned by way of active preamp devices (hint, hint: atmosphere’s own company’s devices.) 2. George feels butt-hurt because atmosphere views his Lightspeed passive preamp as being inferior to atmosphere’s active preamps. 3. The causal observer of this banter would conclude that: (a) atmosphere is entitled to opine about comparisons between his company’s active preamps and George’s Lightspeed passive preamp, because the forum thread is entitled, “Have passive preamps finally come of age?” Atmosphere concludes that the answer to that question is “No,” at least with respect to the Lightspeed passive preamp. (b) George is entitled to take the opposite view of atmosphere’s opinion, notwithstanding his disappointment in atmosphere’s conclusion. |
@mitch2 "I mostly agree. For example, what does "finally come of age" mean?" I think this phrase mostly relates to Tweak1 having discovered a nice balanced stage passive preamp for use in his system having (at the time) a class D amplifier. He wanted to extend his discovery to a discussion about other passive preamps to this group. @tweak1 Thanks for posting this thread query. It's been a bit chippy at times (and continues to be--Lol), but I learned a lot from the contributors herein. |
Mr Db. My comment is borrowed from data analysis fields and applies with equal force here. Whatever distortions are passed to a control device will be passed on to the next device downstream. In other words, I agree explicitly with George and implicitly by inference to your query. This is principle applies equally to passives and actives alike. |
Ugh.... This is from Wiki: “In a home audio system, the term ’preamplifier’ may sometimes be used to describe equipment which merely switches between different line level sources and applies volume control and possibly tone control circuits. Such equipment prepares the signal before amplification but, in fact, no actual amplification circuitry may be involved.” In professional lore, this definition is usually used, as no phono stage is included in a professional mixing console. The term “line stage” was created to alert the home audiophile of the absence of a phono stage in the box. But the converse isn’t necessarily true in the case of a preamp. |
@tweak1 Agreed regarding impedance matching. My ATC active monitors have built-in amps having an input impedance of 10-kOhms. While this is typical for pro amp gear, it’s on the low side for consumer gear. And the adage of sticking with gear from the same manufacturer is wise advice with regard to ATC. Their preamps have output impedances set at 10-Ohms. (Typical pro preamps have output impedances of 600-Ohm or less, so I gather.) |
My Teo Audio Liquid Pre passive is in line with an Oppo DVD player and ATC SCM20-2 active monitors, all connected via Teo Audio liquid metal conductor-based IC’s. I’ve never experienced a more authentic, transparent, three-dimensional musical reproduction experience, including reproduction from my previous audio systems having what I now know to possess perfectly-matched impedances throughout. |
