'Passive Volume Contol Unit' - by LYRITA AUDIO

Sidharth Trehan

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I come back from office and realise that the carpenter has not finished his job in my room. So Audio rack which is dismantled for the time being will still need to rest in the living room.

But, there aint no cure for the 'itch' when you have a new component to be hooked to the rack. So, i did the honors.. connected the 'Passive unit' by LYRITA AUDIO to the Marantz SACD & Quad 909power ...and then i picked an SACD having JACINTHA'S - HERE'S TO LIFE ...and played it... just to think of a box to mummify the Quad 99Pre!

Bhai log, this is just my reaction after listening to the set for half hour.... and i feel that 'mersmerizing' will be an understatement.

- Suddenly i feel i have upgraded the audio rack by 30% !
- The decay in the higher notes sounds to be more detailed and 'smooth'
- Mids have got an even more cleaner and authoritative touch.
- Bass seems to be just fine, but all i heard was smooth jazz and a minimalistic music on it for the short while.

I have some more friends coming home sometime soon, so shall share our joint impressions on the Passive Unit soon.


P.S.
Viren sir ... this is really worthwhile listening and of all the efforts you put in making this and as well as listening to my demands. Much appreciate ur perseverance.


Wishes
Sid
..
 
Hi siddharth,
that's very interesting. Please post some pictures. Please tell us what is function of this passive volume control I have no idea . Hvae fun with the new upgrade.:)
Thnaks.
 
@ Mahi bhai
, ARJ
Sure thing.. Wud rqst a few days, home is in a mess as of now. But i just cudnt stop myself from making initial connections.

@ Kamal ji
Sure thing, but i shall wait a bit for a comfortable session ..rather sessions before i can explain the differences i have in all LYRITA cable solution. For now, the Power-Passive unit are connected via DAC signature. And Passive-SACD via LYRITA's all copper.

Also, shall request you or Viren sir, to drop a short note about the Passive unit ..this piece of addition can do wonders by progressive study by Viren sir on it w.r.t system it needs to be connected with. Hence some would rather not think of picking a pre and shall look in for Passive Units as an option to step up on qualitative output from the existing set in minimal budget.

Wishes
..
 
great!!!!
Have you also tried lyrita pre with your power amp?


I come back from office and realise that the carpenter has not finished his job in my room. So Audio rack which is dismantled for the time being will still need to rest in the living room.

But, there aint no cure for the 'itch' when you have a new component to be hooked to the rack. So, i did the honors.. connected the 'Passive unit' by LYRITA AUDIO to the Marantz SACD & Quad 909power ...and then i picked an SACD having JACINTHA'S - HERE'S TO LIFE ...and played it... just to think of a box to mummify the Quad 99Pre!

Bhai log, this is just my reaction after listening to the set for half hour.... and i feel that 'mersmerizing' will be an understatement.

- Suddenly i feel i have upgraded the audio rack by 30% !
- The decay in the higher notes sounds to be more detailed and 'smooth'
- Mids have got an even more cleaner and authoritative touch.
- Bass seems to be just fine, but all i heard was smooth jazz and a minimalistic music on it for the short while.

I have some more friends coming home sometime soon, so shall share our joint impressions on the Passive Unit soon.


P.S.
Viren sir ... this is really worthwhile listening and of all the efforts you put in making this and as well as listening to my demands. Much appreciate ur perseverance.


Wishes
Sid
..
 
Bhai log, this is just my reaction after listening to the set for half hour.... and i feel that 'mersmerizing' will be an understatement.

- Suddenly i feel i have upgraded the audio rack by 30% !
- The decay in the higher notes sounds to be more detailed and 'smooth'
- Mids have got an even more cleaner and authoritative touch.
- Bass seems to be just fine, but all i heard was smooth jazz and a minimalistic music on it for the short while.

..

i got a very positive experience when i connected my Leben to the passive pre in..basically the Microdynamics and the musical detail increased several fold drawing you more into music. you may find the Bass impact to be a bit less but the details in the bass ie its quality is amazing. Of course Passive Pres dont work for all amp/speaker combination.

Is this a TVC or a resistor based Pre ?
 
Bro, This ones an L-pad resistor based, using a 24step DACT pot.

i got a very positive experience when i connected my Leben to the passive pre in..basically the Microdynamics and the musical detail increased several fold drawing you more into music. you may find the Bass impact to be a bit less but the details in the bass ie its quality is amazing. Of course Passive Pres dont work for all amp/speaker combination.

Is this a TVC or a resistor based Pre ?
 
As I have heard the Quad 909 with Quad 99 pre before, I also felt the same when i connected my setup to the Caiman DAC Pre section (Passive Pre). Since I am using 22L2, the bass is very decent (very accurate and tight). I am trying to replace the caiman Pot with the DACT pot (CT2 10K) so that i dont have to use another box and rca plugs, as i am also planning to change the enclosure for the Caiman dac.

Sidharth, Happy to see that you started enjoying 909 than ever.
 
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@ Sidharth Trehan : Now that IS EXACTLY what I wanted to hear from you... Congrats! and WELL DONE for making this BOLD MOVE towards Passive Pre with your much deserved Quad 909.

Glad to hear from you chief and rather thanks for your guidance towards this wonderful option. Its really worth it and thanks to Viren sir, to have pulled it across. I wonder why Passive units are 'NOT' as popular as they should be, may be cause not many use power amps, but this is one of the most cost effective option to a qualitative upgrade indeed.


I had used & still have a similar L-pad but made out of 'no-compromise parts' i.e. ProPassion by Audio Synthesis UK since 1995. That one uses a Dual mono config : comprising of Mil-spec Shallco Switches with 31-steps, Vishay Bulk-foil S-102 resistors, WBT Topline Female RCA sockets, Pure silver internal wiring and a very thick, solid aluminum extrusion with excellent anodized finished cabinet and wonderfully heavy Solid Gold-plated Brass Knobs. (Both Martin Colloms & Ken Kessler of HiFiNews rated this above $10k active preamps & personally use them in their own systems).

ProPassion (Dual Mono) Single Input | Single Output

2eoa43b.gif

Very enticing i must say, how i wish i could have got the chance to interact with you some months before than how i got through to you recently.


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Incidentally, the day the ProPassion (RCA version) came into my hands in Dec 1995, the same day it kicked out this pre, Quad 34 from the system that I have since 1987.

Thereafter - in 1996 I got another ProPassion but the Balanced XLR IN/OUT version and again, it massacred this $5500 Tube preamp completely.

Audio Research LS-5 II Tube Linestage
xt1yh.jpg

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However - the formula doesn't work with every power amp / speakers due to the following factors:

1. Passive Pre of L-Pad types does not have any GAIN but only attenuates the incoming signal from the Source.

2. The Input Sensitivity of the power amp must be favorable so that the drive from the Source with losses (2 sets of ICs + resistor/s + cable capacitance) must be able to exploit the power amp's rated power. Therefore, if the input sensitivity of Power amp A is 0.775V, it stands a much better chance than say Power amp B of 1.6V Input sensitivity.

3. In above 2, the Input impedance of the power amp also plays an important role. The higher the Input impedance, the better the chances for the passive to work; e.g. If power amp A is 20k? while power amp B is 100k?, B stands a much better chance.

4. The drive from your Source, be it a CD based or TT based should be as High as possible preferably with as low an Output impedance as possible; e.g. Digital CDP Source A is 2V / 300? while CDP Source B is 2.85V / 100?, B stands a better chance again. Generally with a Phono-stage pre, this should not be a problem since they can generate quite a sufficient high voltage to drive the power amp directly.

NOTE: The IC from passive pre to power amp should be kept "as short as possible" and should use "a very Low Cap IC" to combat HF roll-offs. In this section, I've been successfully using the VDH D102 III HB of metre length in my setup. This cable exhibits an extremely low capacitance of just 37pF per metre core-to-core.

Noted the pointers sir. I for now have the DAC signature I/C & also Lyrita's I/C both of which i shall use for the time being and assess for a audible difference.


Thanks a ton to you & Viren sir
(you well know that i mean every bit of it!)
 
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Sajith,
its a zen like feeling with every bit of improvement especially when you are on a tight budget.

Thanks for your comment brother. Appreciate it.


wishes
..

As I have heard the Quad 909 with Quad 99 pre before, I also felt the same when i connected my setup to the Caiman DAC Pre section (Passive Pre). Since I am using 22L2, the bass is very decent (very accurate and tight). I am trying to replace the caiman Pot with the DACT pot (CT2 10K) so that i dont have to use another box and rca plugs, as i am also planning to change the enclosure for the Caiman dac.

Sidharth, Happy to see that you started enjoying 909 than ever.
 
saab ji,
Gmailed you.

My regards
..

@ Sidharth Trehan : Appreciate deeply your kind words & gesture.

One thing though about passives - when the going gets 'good', nothing can touch it or even come near it. The transparency allows you to practically have a 'see-through' into the soundstage, literally looking thro' a Zeiss glass and capturing the 3-dimensionality of the soudscape; and also if impedances match favorably you'll get a wonderfully deep, soul-filling tone across the entire audio bandwidth, right from very low bass up to the shimmering of the Zildjian cymbals and their harmonics. Its then all up to the capabilities of the power amp and the speakers.

But from this wonderful situation as mentioned above, one change of a component (be it source related or power amp) and the so called "magic" would disappear out of your audio room. I feel it restricts you from upgrades. The 909 itself is a fairly fine performer albeit its idiosyncrasies that should be addressed at a latter date to improve certain aspects of the amp that Quad purposely didn't do. The amp is easily capable to support speakers 4 times its cost. Coming to source upgrades in the future, you'll always have to seek for high-output drive types. As for dacs, most are under 3V output (typically between 2.2V ~ 2.5V RMS) except just a few. When I got my passive in 1995, I already had the Theta Pro-Gen III dac in my system that did over 7.5V RMS (0dB full-scale) at 20? output impedance from the RCA outputs so my choice of power amps were wide open. Later, when I upgraded from the Pro-Gen III to Va (24/96), the RCA output was still 6.5V RMS (0dB full-scale) hence it always kept my power amp upgrade route open.

Finally - coming to Vishay Bulk Foil S-102 resistors, I'm yet to come across a more musically complete and better resistor than this. These are very expensive at over $10 easily a pc for standard values going up to $50 a pc for higher values. This shoots up the price of a passive tremendously. But the sonic realization is so thorough that you'll tend to get over the price soon.

regards
 
A beautiful, well-constructed speaker with class-leading soundstage, imaging and bass that is fast, deep, and precise.
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