Tekton Double Impacts
I believe I had the volume up to between noon and 2 using a streaming device as the input before Tom’s amp started soft clipping, which was on 90 db speakers, on the 8 ohm taps. It also depends on the level of the recording. Les Zeppelin needed to be raised much higher than say Pearl Jam, for instance. The entire system sensitivity and desired level of listening comes into play heavily for sure. |
First, kudos to Dave (Dlcockrum) for what IMO is an astute, perceptive, thorough, and exceptionally well written review he provided yesterday of his experience with David_Ten’s excellent system. And likewise with respect to the similarly well written comments provided by Laaudionut. Regarding inline attenuators, for many and probably most applications I would suggest going with the Rothwells rather than the Harrison Labs devices. Based on measurements I recall that one of our members provided here some time ago the resistor values used in the Harrison devices are low enough to be a problem in many systems. Especially if the attenuator is driven from a tube-based component which has coupling capacitors at its outputs. FYI, resistance measurements I’ve taken of 10 db unbalanced Rothwell attenuators that I have show that they consist of a 22K resistor in series between their input and output, and a 10K resistor in shunt between their output and ground. Therefore, depending on the input impedance of the component whose input they are connected to, the component providing the signal to them would see a load impedance in the rough vicinity of 30K or so. The corresponding numbers for the Harrison Labs attenuator are far lower. Re the gain questions that have been discussed, first, it’s probably fair to say that among the countless amplifier models that are available gain and maximum power capability tend to have a **loose** correlation. But many examples can certainly be found of lower powered amps having higher gains than higher powered amps. Charles, it can be calculated from the specified 0.7 volt sensitivity and 8 watt power rating of your Franks that their gain is approximately 21 db when their 8 ohm tap is used to drive an 8 ohm load. IIRC your speakers are nominally 14 ohms, and given the Frank’s output impedance of 1.8 ohms (as stated in a TAS review I’ve seen), their gain from the 8 ohm tap into 14 ohms would be close to a db more than that, or around 22 db. Re the Pass XA60.5, like most Pass amps it has a specified gain of 26 db, which corresponds very closely to what John Atkinson measured in Stereophile’s review of that amp. Correspondingly, it has a specified sensitivity of 1.1 volts for its rated output of 60 watts into 8 ohms. However its maximum power capability into 8 ohms (after transitioning from class A to class AB) is 130 watts per JA’s measurements, which can be calculated to require an input of about 1.6 volts to be reached. Best regards, -- Al |
Lol Aric, see how much I trust you by giving you free reign on designing my gear? Little did I know I had a tube regulated power supply. Brian still hit the Motherlode with that name though! 😃 All of the discussion on gain might make me gain some insight on preamp/amp interaction. Aric's predilection for Zepplin and Pearl Jam explains his propensity for higher gain 😈🔉🔉🔉🔉 With my speakers I can't come anywhere close to 10 o'clock on the VC. 9 o'clock is quite loud on most recordings with 8:30 being where I usually listen at. I can see where have less gain I would have a wider spectrum on the VC to choose from. I'll look into a Rothwells attenuator to experiment with. |
Tom, I agree with Al regarding the attenuators, Rothwell vs Harrison Labs and for the reasons he gave. They aren't expensive so you may want to get several different ratings to see which provides the desired level of reducing db (excess gain). For example 4 db reduction may not be enough and 20 db decrease could be too much. These devices are pretty transparent and shouldn't alter the sound quality. I'd shoot for a level that allows you to listen at your typical levels with the VC near or at the 11AM to 12 noon position. Charles |
Since the 300B amplifier's architecture uses dual 6SN7 stages, and I omitted cathode bypass for the benefit of greater detail, the gain of the amplifier is very close to that of an integrated, however two un-bypassed stages is just shy of being able to be driven by line level (bypassing the cathodes fixes that but at the expense of some natural cathode feedback that occurs and as such, some micro-resolution is compromised- so I chose against bypassing them). Since 2 stages is just shy- and three stages is too much so to speak, the solution I chose was to incorporate an input level potentiometer on the amplifier which occurs between the preamplifier and the amp's inputs. A plug in attenuator is simply a series fixed resistance followed by a fixed shunt resistance (which is many cases loads the input excessively), the potentiometer performs the same duty except we're able to select the 100K shunt between input and ground which is an easy load for the preamp's output to drive. On another note, I'm not sure if I'm over-staying my welcome by posting details about my gear on what is the Tekton thread, and I enjoy posting here, but if any think it's more prudent to bounce any of these conversations to an Aric Audio specific thread, feel free to post at the link below: https://forum.audiogon.com/discussions/aric-audio-systems-unlimited-preamp Best wishes, Aric |
I have to say, I am truly impressed with the tonal qualities and imaging of the Duelund PIO caps used in the outputs of the Motherlode! I still say that the True Copper Audyns are a hair- and I mean just a "hair" less smooth, but with the same overall presentation and at a much more economical level. However I haven't stopped listening to the Motherlode since I buttoned the bottom cover on, and I'm hearing things I've never heard sound so real in my system before. Having never personally heard "The Dude", I can't say how much of a difference there is (if any), but having the same basic architecture in place, and similar high end components used throughout, I can only surmise that the Motherlode is a "sister from anutha mister". Best wishes, Aric |
Aric - I owned a basic Dude preamp for a couple of years. It was very good. Paul would use his excellent design and build it to your price point. I never heard one with Duelunds but from what I've been told they were something special. Grannyring (Bill) has a lot of knowledge regarding the Dude preamp if you should have questions. (Hope I didn't just speak-out-of-turn Bill) |
@sbayne - Thank you! Yes, I've actually been chatting with Bill about some of the differences and similarities between the two designs over on another thread. It appears Paul's design was highly sought after and many different versions were offered. It's very interesting and cool to see all of the variations out there. |
@sbayne - Thank you! It’s been a really neat test comparing the same tracks back to back on the "Motherlode" and then my own personal unit using 6SN7’s and the True Copper caps. The all film-capacitor power supply using a toroid (instead of iron) really helps the black background become more, well, black. I’m sure there’s lots of break-in left to do, but even out of the box, the Duelunds have a quick-paced liquidity and great bass. I’ve been testing it with my SE 150-based amplifier, and it’s a great match. It has plenty of grip and speed even on my 90db @ 1 watt efficient speakers (old school 6.5" Audax Aerogel MTM’s designed by Joe D’Appolito). |
@sbayne-Thanks! However, as I have mentioned, Bill's(grannyring) guidance, and Aric's willingness and talents to pull this off, take centerstage. I cannot begin to express my excitement about seeing and hearing it in person! On an unrelated note, after taking delivery of The Motherlode next week and the DI-SE's in the coming few weeks, my attention will soon turn to a dedicated DAC with excellent volume control. Currently I am utilizing my Oppo 205 as a transport and DAC to stream Tidal, but want to take it up a notch. I am eyeing the Hegel HD30, and I see there is a used one on the site. However, in my attempts to mitigate any more multi-thousand dollar audio investments, as well as stave off divorce, if there is a better bargain, as well a better performer, I would look forward to any guidance on the matter. To keep the integrity of this thread and not veer too far off its subject matter, you can message me with your thoughts and experience. Thanks in advance! Cheers! Brian |
As several A'goners have requested, here is a link to the The Motherlode preamplifier built for Laaudionut: http://aricaudio.com/products.php?product=ML6SL7MM Aric |
@laaudionut Brian, following up on your findings vis a vis the Pass XP-20... Earlier, I will tell you, as someone who currently has Pass gear and the XP-20 specifically, that I was underwhelmed from the moment I introduced it to the XA 60.8’s. Yes it was detailed and un-coloring, but the imaging was poor, the soundstage seemed compressed...it just did not sound,"musical" to my ears and taste. The moment I was able to to an A-B comparison using Aric’s loaned preamp, I knew I was on to something special.and more recently, Currently I am utilizing my Oppo 205 as a transport and DAC to stream Tidal, but want to take it up a notch. Were you using the Oppo with the XP-20 or did you have another front end? Wondering if you found the same when using another front end? |
I've had both with my D.I.'s being I believe the most current version. I would describe the 2 models performance as very similar with the D.I.s having a deeper bass response, although I doubt most would deem the Electrons to be lacking in that department. The D.I.'s also IMO are slightly smoother responding with a shade more depth. However, those features could just be the most recent modification that have been added to the design. I sure liked the weight of the Electrons a lot better. LP |
I'm curious on getting different opinions on room treatments that DI/SE owners have found effective. My current dedicated room is about 21x14.5x9. When I designed this room I tried to use ratios that were favorable. It has double thickness drywall, vinyl plank flooring over concrete, with carpet over that in the rear half of the room. The front wall has MDF rectangular columns to help break up and diffract sound waves. The rear wall has DIY 3.5" rockwool absorbers over most of that wall. The room to my ear is on the bright side with a bit of slap echo. As I do not find the DI's bright, I don't mind a room on the "live" side. But I suspect some side wall treatment is in order. The other issue is bass response. I received my Hsu sealed subs. They came with a nice test disc. This was an eye opener. While I knew the DI's had tight bass in my room, testing really reinforced my impression. There was a marked null at 40-50hz, and then better output to 30hz (the tuning frequency of the port), with little below that. I have pretty much an equilateral triangle with speakers/chair. Moving this all out further into the room placed my listening spot closer the rear wall, and with the subs in the front corners, I did clearly improve the null. (40hz still a bit down in response) Response now in the room has good extension to 20hz and at least by ear fairly smooth up to 80-100hz where there is a bit of a peak. So in an effort to improve the acoustics of my room I've been reading all kinds of posts/articles--- and advice is all over the place. Some say clearly to treat first reflection points, others say this will close down the sound stage (which I really would not desire). ? use diffusion instead on side walls a combination of diffraction/absorption. Bass traps to smooth the 80hz peak (and how the heck do bass traps "know" I only want to dampen at 80hz, not 40hz??). I am limited as only one corner is available for traps (subs in front two, door in the other). I know in the end I'll have to probably just try things. Just hoping to avoid costly mistakes. Thanks guys. |
corelli: We have discussed this several times above (but its a long thread, right?). Have built custom wall hangings that kill reflection behind AND between my two DIs and this alone has made a tremendous improvement in a large but poor acoustic space. Doing room correction afterwards fine-tunes the result but my experience in the studio and audiophile worlds is that physical room correction always beats signal alteration. Have found that removing the reflection behind the speakers allows them to stand in their own glory and this improvement is arresting in strength. |
Update on Aric Audio's, The Motherlode. The long awaited delivery took place yesterday afternoon. Taking into consideration that the big Dueland capacitors can take a few hundred hours to break in, and I am using freshly unboxed NOS tubes from Andy(shout out to Vintage Tube Services), I am already in awe of its sonic qualities. Big, punchy bass, a huge, articulate, three dimensional soundstage, dead quite in both the line stage and phono stage...this masterwork is destined to continue to bloom into an audio bouquet that stimulates all the senses...said for taste, suffice it to say! I am keeping it on and running a signal through it to speed up break in, and will report back in a few hundred hours or so. Aric, you are a credit to your craft...this piece is stunning in every way! Cheers and happy listening! |
Came across this recent review of the Valvet E2 (link posted below). I've posted the link because it is a low power Class A Solid State amplifier that may be a pairing to consider with the Double Impacts. It is also 'reasonably' priced for a Class A amp. [Please note that I do not have any connection to the review site nor the distributor / seller] Review: http://www.10audio.com/valvet-e2.htm Audiogon Listing: https://www.audiogon.com/listings/solid-state-stereo-amplifier-handmade-in-germany-new-2018-01-27-am... |
David, the build on this is a thing of beauty. If it sounds as good as it looks, it'll be a winner. And, as you suggest, probably would be a great match with the DI's. Listening tonight to Yo-Yo Ma playing Vivaldi's Cello Concertos on a Sony box set. Man, this one CD alone is worth the cost of the whole set! The DI's render this beautifully, full of detail and ambience. I'm enjoying my pair of Hsu ULS-15 subs coupled to the DI's. I'll save my thoughts until after I finish the acoustic treatments to my room. Picked up materials today for a large soffit bass trap that will run the full length of the back wall/ceiling. The remainder of the treatments will be commercial products that will be decided upon in the next week or so. |
@corelli I've had Yo-Yo Ma's Inspired By Bach : The Cello Suites in rotation of late...I'll pull up the Vivaldi Cello Concerts. Right now I'm flying with Rudresh Mahanthappa's 'Bird Calls' - Fabulously fleshed out and rendered by the SEs. It might be very interesting to compare the Pass XA-25 to the Valvet E2, which is single ended with 12/20 Class A Watts into 8/4Ohm. |
Man, I have DIs in a 10x13x8 and now they look diminutive with these acoustics I'm placing in the room. Cut this Yo-Yo biz in here. Never trust a guy whose name sounds like a child's toy. How about some Jimi Hendrix? Good. Sounds American and great on DIs. For your classical fix, let's do Claude Debbusy, Le Mer. It's light. Angular. It has spaceout. |
