Active Ascent of Mount Olympos

[LL21]

Bruce,

It is not an uncommon assumption, regarding active speakers, that they have the amplification built into the loudspeaker cabinet. This actually defines a self-powered speaker which may or may not employ an active line level crossover.

An active system uses a powered line level crossover as opposed to a speaker level passive crossover. The technical (and in my opinion, sonic) benefits of the former FAR outweigh the few negatives which one might raise. It is a different story if one looks at active speakers from a commercial standpoint. Very few skilled and knowledgable (rarer than you might imagine) loudspeaker designers also happen to be talented enough to build reference quality electronics and to amalgamate the two into an ultra-high fidelity package.

In the future we will no doubt see more digital-to-analogue converters using their prodigious on-board DSP power to provide a digital active crossover function with multiple dedicated line level analogue outputs for each of the low, mid, hi, etc (each requiring a separate channel of amplification). The real trick is designing the optimum crossover in the first place (be it passive, active digital, or active analogue) since this is not something that one can master in situ. A digital active crossover approach mandates a strong collaboration between the digital manufacturer and the loudspeaker designer (e.g. Devialet partnering with Vivid Audio to develop an active version of their GIYA G1).

Being somewhat dedicated to the vinyl path (cough, cough) I gravitated strongly towards an active system where all filtering is performed in the analogue domain. I know that some people will scoff at the idea of using op-amps to perform the crossover filtering but this is BY FAR the lesser of two evils compared to the large value passive components inside most loudspeakers (where steeper slopes are desirable - and I would argue mandatory in the absence of THE perfect driver/s). No doubt someone will be concerned about phase shift with higher order crossovers (be they passive or active) but I am yet to read a paper in a peer reviewed journal where the effects of "modest" group delay are audible to the human ear under unbiased conditions.

Very interesting post. I did once speak with a speaker designer who also knew Wilson speakers extremely well. His view was using the Wilson active crossover, one could bypass some of the passive crossovers of the Wilson X1/X2 and then dedicate 1 amp to drive bass and 1 to drive the uppers. Wilson of courses does not recommend this, but given the CV of this speaker designer, I remain intrigued by his idea. I think in addition to control, linearity, I suspect based on what I have read he may also feel that coherence might also be improved...of course on the assumption the execution is exemplary.

 

[Young Skywalker]

I would also like to commend you on the quality of your system photographs. They are outstanding. Great light, focus and composition.

Thank you, Peter.

 

[Young Skywalker]

Very interesting post. I did once speak with a speaker designer who also knew Wilson speakers extremely well. His view was using the Wilson active crossover, one could bypass some of the passive crossovers of the Wilson X1/X2 and then dedicate 1 amp to drive bass and 1 to drive the uppers. Wilson of courses does not recommend this, but given the CV of this speaker designer, I remain intrigued by his idea. I think in addition to control, linearity, I suspect based on what I have read he may also feel that coherence might also be improved...of course on the assumption the execution is exemplary.

Assuming exemplary execution, a fully active crossover approach has a landslide of benefits (particularly in the bass) over a passive crossover approach. Andy Payor of Rockport Technologies dipped a toe in the commercial active waters recently with a semi-active version of his flagship Arrakis loudspeaker (including outboard active line level crossover). As I mentioned earlier in this thread, Laurence Dickie of Vivid Audio is working with Devialet to develop a fully active (digital domain) version of the GIYA G1. Laurence, of course, was also responsible for the Bowers and Wilkins Nautilus, a 4-way fully active design with dual mono active line level crossovers requiring 8 channels of amplification.

 

[LL21]

Assuming exemplary execution, a fully active crossover approach has a landslide of benefits (particularly in the bass) over a passive crossover approach. Andy Payor of Rockport Technologies dipped a toe in the commercial active waters recently with a semi-active version of his flagship Arrakis loudspeaker (including outboard active line level crossover). As I mentioned earlier in this thread, Laurence Dickie of Vivid Audio is working with Devialet to develop a fully active (digital domain) version of the GIYA G1. Laurence, of course, was also responsible for the Bowers and Wilkins Nautilus, a 4-way fully active design with dual mono active line level crossovers requiring 8 channels of amplification.

Thanks....yes, I read and posted about an interview with Payor, Dickie and TAD's designer regarding active vs passive speakers. I have also read Fleming Rasmussen's view (Gryphon Audio). I have now heard the active Rockport Arrakis...cannot comment on active element itself since the system was all new. I am told it provides much greater setup flexibility.

 

[Mosin]

They don't have to be built in. Active means that the crossover network is an active circuit. It will have active parts like op amps. A passive crossover has only passive parts like caps, resistors, and inductors. These can be outside the speaker as well. His speakers just have most of the amps outside the speakers. Not sure if the crossover itself is inside or outside though. My speakers are considered active as well. The active crossover for my speakers is in the bass amplifier. The amp that powers the panels, gets the signal from the bass amp.

Does anyone know if Jon Marovskis of Janis was first to do this?

 

[Young Skywalker]

Some new photos...

 

[Young Skywalker]

Some larger versions of earlier photos...

 

[Young Skywalker]

Some of you might be curious as to which tools I use to set up my cartridges. Shown below are the UNI-P2S and UNI-Protractor from Acoustical Systems.

 

[Lee Henley]

Thats a nice looking system you have their mate and a wonderful room, bet it sounds awesome

 

[PeterA]

Great photos, as usual. There is no doubt you are getting very precise/accurate set up with those tools. A great example of German engineering, along with your turntable. I noticed the stand under the Minus K is also made by them. I was not aware that they offer a stand. It looks great and must sound even better. Brinkmann is one of the few turntables that I considered. It's excellent.

 

[Young Skywalker]

Thanks for the nice feedback, gents.

Yes, Peter, the Acoustical Systems tools are very good indeed and for this perfectionist they are the only choice.

I had factored a Minus K isolation platform into the equation when I moved from my suspended Basis 2800 to the non-suspended Brinkmann Audio Lagrange. After doing a good deal of research into the Minus K I settled on their 100BM-1 isolator, for its minimum 0.5 Hz vertical natural frequency as well as its large working surface area which provides the broadest scope for locating the payload's centre of mass. Coming up with an elegant solution for accommodating the physical bulk of the BM-1 was my next challenge and despite its somewhat "purposeful" aesthetic the matching stand made a lot of sense. Bridging the stand's lower cross member braces with my own custom sized granite shelf (atop six round neoprene pucks) provided the ideal location for the Brinkmann Lagrange power supplies (the vacuum tubed Ront II for the motor and the stock solid state unit for the bearing oil heater). I seriously doubt that the granite shelf, chosen for its elegant appearance, has any meaningful sonic impact, be it negative or positive, on the performance of the Brinkmann power supplies but it does add some low slung ballast to the stand which is no bad thing. The steel stand itself is not well damped but in the context in which I am using it this is not a relevant factor. I can hit the stand as hard as I like and the turntable will never miss a beat. Friends joke that my analogue front end is earthquake proof... it is.

The Brinkmann turntables are superb but like all commercial products they have their own unique set of strengths (many, in fact) and a few weaknesses. The trick is to know how to address the few weaknesses in ANY turntable if one seeks to maximise the sonic potential. I have taken care of this job recently with spectacular results (see this link for a photo).

My principle criteria in choosing a turntable include:

• platter mass greater than 10 kg (more is better)
• platter extremely well damped
• very precisely machined bearing (preferable sealed hydrodynamic) and platter with vanishingly low levels of horizontal and vertical run out
• single external motor with vanishingly low levels of cogging
• belt drive principle (with potential to be changed to thread drive principle)
• the ability to accommodate one or more pivoted tonearms with an effective length of 12"

 

[Young Skywalker]

Some new photos which show the modifications to the Lamm LP2 Deluxe phono preamplifier and LL2 Deluxe linestage preamplifier. Also included a new photo which shows the room with some natural daylight.

First up, the modified Lamm LP2 Deluxe phono preamp...





For a point of comparison, here is a photo of the stock Lamm LP2 Deluxe...



Here is a photo of the modified Lamm LL2 Deluxe linestage preamplifier...



Finally, my room with the curtains open to let some natural light in.

 

[Audioseduction]

Beautiful room and outstanding equipment! Thanks for sharing.

 

[MylesBAstor]

Some new photos which show the modifications to the Lamm LP2 Deluxe phono preamplifier and LL2 Deluxe linestage preamplifier. Also included a new photo which shows the room with some natural daylight.

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What mods did you do to the LAMM? Just bypassing some caps? Did you swap any of the tubes out?

 

[Young Skywalker]

What mods did you do to the LAMM? Just bypassing some caps? Did you swap any of the tubes out?

Hi Myles,

The Lamm LP2 Deluxe was purchased from my friend in Germany, WBF member Syntax. He had already performed some modifications to the unit with the assistance of his technician. These included replacing the stock pressed metal RCA connectors with solid copper ones from ETI, replacing the standard loom/connectors between the final gain stage and the output RCAs with a direct run of teflon-insulated silver wire, stock signal coupling caps replaced with NOS Cornel-Dubilier silver/teflon caps, NOS WE 417A tubes, and custom Jensen SUTs (much larger than the stock Jensen SUTs).

When the unit arrived here in Australia it had been through Hell with shipping and customs and there was some internal damage, capacitor lead detached from PCB, etc. I took the unit along to my local technician, Mr Elson Silva, who worked his magic by tidying up a lot of the soldering/layout and replacing some of the crumbling stock carbon resistors with high temperature types from Vishay, each mounted to their own heat sink. The NOS WE tubes have long since died and I am now running with a matched set of super quiet NOS Raytheon 5842 Q tubes. I utilise the Lamm's MC input for my Lyra Dorian Mono cartridge while the MM input sees external custom "Syntax" Jensen SUTs matched to my Miyabi Alnico and Lyra Olympos stereo carts.

The Lamm LL2 Deluxe was purchased in stock form from an audiogon seller based in Mexico. When this unit arrived it had also been through Hell from customs, presumably because they were searching for drugs as a result of the unit's origin. There was quite a bit of damage internally with the unit arriving upside down in its shipping crate and with the supporting feet detached and rolling around inside. I put everything right and was able to get a handle on the performance of the stock unit before embarking on any performance enhancing modifications. The modifications which were eventually performed, again courtesy of the expert technician Mr Elson Silva, included replacing the stock pressed metal RCA connectors with solid copper ones from ETI, the stock signal coupling caps were replaced with Mundord M-Cap Supreme silver/oil caps, the by-pass caps were replaced with copper/teflon V-Caps, the stock carbon volume pots were replaced with stepped Vishay resistor attenuators from DACT (much better channel-to-channel tracking and greater transparency), and two critical diodes in the power supply were swapped out for ultra-fast recovery soft types from Reference Audio Mods. I have played around with NOS tubes in this unit to great effect. Currently running NOS RCA Cleartop 12AU7s in the first gain stage and NOS Telefunken ECC88s in the second gain stage. I am waiting to take delivery of some NOS Telefunken Smoothplate 12AU7s and NOS Siemens 6922s with gold pins. Rectifier tubes for both Lamm units are NOS RCA 6X4s. I have fancy silver fuses in both units but my scientific PhD training tells me that this is stretching the bounds of credibility.

Forgot to mention that all signal tubes now have Herbies damping devices fitted. I am not sure how effective these things are in absolute terms but given that the tube sockets are mounted to the PCB which is rigidly coupled to the chassis and also carries the power supply transformer I figured that every little bit of defence against microphonics helps.

 

[Young Skywalker]

Beautiful room and outstanding equipment! Thanks for sharing.

Thanks for those nice comments, George. Your system looks very neatly laid out and I love the artwork which hangs between your M-L speakers.

 

[MylesBAstor]

Hi Myles,

The Lamm LP2 Deluxe was purchased from my friend in Germany, WBF member Syntax. He had already performed some modifications to the unit with the assistance of his technician. These included replacing the stock pressed metal RCA connectors with solid copper ones from ETI, replacing the standard loom/connectors between the final gain stage and the output RCAs with a direct run of teflon-insulated silver wire, stock signal coupling caps replaced with NOS Cornel-Dubilier silver/teflon caps, NOS WE 417A tubes, and custom Jensen SUTs (much larger than the stock Jensen SUTs).

When the unit arrived here in Australia it had been through Hell with shipping and customs and there was some internal damage, capacitor lead detached from PCB, etc. I took the unit along to my local technician, Mr Elson Silva, who worked his magic by tidying up a lot of the soldering/layout and replacing some of the crumbling stock carbon resistors with high temperature types from Vishay, each mounted to their own heat sink. The NOS WE tubes have long since died and I am now running with a matched set of super quiet NOS Raytheon 5842 Q tubes. I utilise the Lamm's MC input for my Lyra Dorian Mono cartridge while the MM input sees external custom "Syntax" Jensen SUTs matched to my Miyabi Alnico and Lyra Olympos stereo carts.

The Lamm LL2 Deluxe was purchased in stock form from an audiogon seller based in Mexico. When this unit arrived it had also been through Hell from customs, presumably because they were searching for drugs as a result of the unit's origin. There was quite a bit of damage internally with the unit arriving upside down in its shipping crate and with the supporting feet detached and rolling around inside. I put everything right and was able to get a handle on the performance of the stock unit before embarking on any performance enhancing modifications. The modifications which were eventually performed, again courtesy of the expert technician Mr Elson Silva, included replacing the stock pressed metal RCA connectors with solid copper ones from ETI, the stock signal coupling caps were replaced with Mundord M-Cap Supreme silver/oil caps, the by-pass caps were replaced with copper/teflon V-Caps, the stock carbon volume pots were replaced with stepped Vishay resistor attenuators from DACT (much better channel-to-channel tracking and greater transparency), and two critical diodes in the power supply were swapped out for ultra-fast recovery soft types from Reference Audio Mods. I have played around with NOS tubes in this unit to great effect. Currently running NOS RCA Cleartop 12AU7s in the first gain stage and NOS Telefunken ECC88s in the second gain stage. I am waiting to take delivery of some NOS Telefunken Smoothplate 12AU7s and NOS Siemens 6922s with gold pins. Rectifier tubes for both Lamm units are NOS RCA 6X4s. I have fancy silver fuses in both units but my scientific PhD training tells me that this is stretching the bounds of credibility.

Forgot to mention that all signal tubes now have Herbies damping devices fitted. I am not sure how effective these things are in absolute terms but given that the tube sockets are mounted to the PCB which is rigidly coupled to the chassis and also carries the power supply transformer I figured that every little bit of defence against microphonics helps.

Thank you for the very thorough response!

Laughed my head off at the beginning of the third paragraph. Sure you didn't at the time!

 

[Young Skywalker]

Thank you for the very thorough response!

Laughed my head off at the beginning of the third paragraph. Sure you didn't at the time!

Thank you, Myles. I certainly wasn't laughing when I first opened the crate for the Lamm LL2 Deluxe but looking back I can see the humour in it. In a way, having a unique story behind each component acquisition makes them all the more special. A good friend once mentioned that "the true audiophile is born to suffer". I have since learned to balance that hypothesis with the idea of patience as a virtue.

 

[MylesBAstor]

Thank you, Myles. I certainly wasn't laughing when I first opened the crate for the Lamm LL2 Deluxe but looking back I can see the humour in it. In a way, having a unique story behind each component acquisition makes them all the more special. A good friend once mentioned that "the true audiophile is born to suffer". I have since learned to balance that hypothesis with the idea of patience as a virtue.

Someday will have to tell the story about the 50k de Paravicini Alchemist amplifier and the condition it arrived in. at least you were made whole!

 

[Young Skywalker]

The Acoustical Systems ARCHON moving coil phono cartridge has arrived. It replaces the Lyra Olympos.