too much gain

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Shredder

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Re: too much gain
« Reply #20 on: 19 Aug 2017, 08:23 pm »
I am interested in balanced. Thanks for the info.

Shredder

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Re: too much gain
« Reply #21 on: 19 Aug 2017, 08:27 pm »
O have not tried the attenuators before the pre. I will give that a shot.

Nordkapp

Re: too much gain
« Reply #22 on: 19 Aug 2017, 08:48 pm »
Check out the Schiit Freya too. Passive, jfet buffer or tube gain.

Shredder

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Re: too much gain
« Reply #23 on: 20 Aug 2017, 10:54 pm »
Opnly Bafld- I just tried the attenuators before the pre and voila, dynamics have returned. More punch, definitely more impactful bass. I played some really dynamic songs that i know well (Paranoid Android by Radiohead, Boogie Woogie Waltz by Weather Report, etc). Definite improvement and just as importantly retained the reduction in noise floor attained with the Endlers. This is not just wishful thinking as the sweet spot for attenuation changed from 16db reduction to 12db. The placement change is definitely having an effect.

No idea why this makes a difference but I will take it.

BTW, I also tried reducing gain with the Cary's Input Level dials, but they also hampered sq.

In the long-term, I am considering high efficiency speakers (Daedalus, which are a great match with the MW). That will likely necessitate a passive (or 0db gain pre). Good to know that there are tried and true options. Given the 30 day trial, i may try the Tortuga sooner than later.

Thanks for the help.

Shredder

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Re: too much gain
« Reply #24 on: 21 Aug 2017, 02:39 pm »
More information. Cary told me that the Atlantic's 3v gain is too much for the pre in balanced mode, which is only built to handle a smidge over 2v. Sending it 3v leads to overloading/distortion. That is, of course, the issue I have been trying to resolve with the attenuators. I also assume that issue is why adding the attenuators before the pre was superior to adding them at power.

So, reducing the Lampi to 2v output will make it a better match with the Cary pre. Sounds like a couple of you have tried that. I understand that this approach won't reduce the gain that much. I am wondering, however, whether it will degrade sq? Please let me know.

thanks for all the help.




kernelbob

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Re: too much gain
« Reply #25 on: 21 Aug 2017, 03:18 pm »
That seems like an awfully low threshold for a preamp to overload.  Why add more attenuators, cables, connections in line with the existing preamp's attenuators just to pamper a preamp that already contains switches and/or potentiometers?

I don't have experience with the Lampi Atlantic, but my Golden Gate has a similar output level, actually higher at 5v.  I auditioned a Golden Gate with the built-in attenuator and source switching.  At attenuation down to about -10 dB they were very close, but at more attenuation, the Tortuga was superior.  The Tortuga doesn't lose dynamics or low level detail with increasing attenuation.  Channel separation is superb, better than any active preamp in my experience, and the bass remains as powerful and articulated as at full volume.

The key to the Tortuga is that there are no switches or potentiometers (or capacitors for that matter) in the signal path.  Even the input source switching is done by LDRs.  Plus, you get the benefit of input impedance control from the remote and in the LDRxB, the opportunity to have absolute phase/polarity control with one click from the remote.  The computer controlled attenuation settings can be re-calibrated at any time (again from the remote), so any long term drift of the LDR's attenuation is a non-issue.  I usually recalibrate mine every few months or so, but then I tend to be obsessive about my system.

Seems to me to be time to move on.

Best,
Robert

leftside

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Re: too much gain
« Reply #26 on: 21 Aug 2017, 05:08 pm »
Yes, that's a pretty low threshold for a preamp. For example, here are the specs for my preamp:

Maximum Input Signal
High Level:
5V Unbalanced
10V Balanced

Voltage Gain
High Level Input to Main Output: 15dB

Shredder

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Re: too much gain
« Reply #27 on: 21 Aug 2017, 07:36 pm »
Hmmmm, very sad as I love the Cary. I always gravitate toward tubes and am somewhat hesitant to go a different route. Perhaps the tubed Lampi and warmish Modwright suffice. And, if this really is a mismatch, I assume I am losing much of the benefit of the Cary.

kernel bob-do you use the external Tortuga power supply? Given the design, it is not clear why that would be of benefit.

Thanks.

Shredder

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Re: too much gain
« Reply #28 on: 21 Aug 2017, 09:43 pm »
And,any idea how Tortuga compares to Music Girst baby reference which also gets great reviews?

kernelbob

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Re: too much gain
« Reply #29 on: 21 Aug 2017, 09:53 pm »
kernel bob-do you use the external Tortuga power supply? Given the design, it is not clear why that would be of benefit.

I use an Optima marine battery as a power source.  It's simple to set up, you basically just need the correct plug for the Tortuga and connectors on the other end for the battery terminals.  I keep the smallest trickle charger I could find permanently connected to the battery.  I've never noticed when the charger is active or not.  On the Tortuga LDRxB-V2 (the one I have) using battery power took the sound to significantly higher level.  Morten has indicated that the V25 boards can use battery power, but that it shouldn't make as much (if any) of a difference.  When I get my V2 upgraded, I'll stick with the battery supply if nothing else to save on the cost of another power cord.  Give Morten a call and he can give you more details.

Robert

kernelbob

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Re: too much gain
« Reply #30 on: 21 Aug 2017, 10:26 pm »
Hmmmm, very sad as I love the Cary. I always gravitate toward tubes and am somewhat hesitant to go a different route. Perhaps the tubed Lampi and warmish Modwright suffice. And, if this really is a mismatch, I assume I am losing much of the benefit of the Cary.

I often hear folks talk about adding a tubed component into their system to tilt the sound this way or that (e.g. adding "sweetness").  I think this is misguided.  The job of any component is to pass the signal with as little alteration as possible, not to flavor the sound like adding an herb to a soup.

I switched from a tube preamp (an Audio Research REF3 at the time) to the Tortuga LDRxB-V2.  The Tortuga surpassed the REF3 in every way.  The sound stage is wider (much better channel separation) and deeper.  Bass is more dynamic, tighter, more extended into the lower frequencies, and has with more articulation.  High frequencies are cleaner and with more air.  Most importantly, musical instruments and voices are presented as separate entities.  The signatures of different pianos, violins, even different recording venues are more obvious thanks to both great macro and micro dynamics.  With the Tortuga, you aren't losing the qualities that you value in a good tubed unit.

The problem with the Tortuga (and I've discussed this with Morten) is that people assume a unit will have a certain value-for-the-money based on the price point and that their expectations are that of a modestly priced preamp.  My experience is that the Tortuga performs far above its price and outperforms much more costly preamp/controllers.

By the way.  I also value what tubes can do.  That's why I'm using the Lampizator Golden Gate DAC and have a pair of Lampizator 211 Balanced monoblocks on order.  I currently use modified Kronzilla monoblocks (each running a quad of 300BXLS tubes) on the mid/treble and a pair of Spectron monoblocks on the bass.  Regarding the Golden Gate, I'm not using it to add a "tube sound" to the system, but for the realism of the music.

P.S.  The Golden Gate is even better and neutral when I added a set of tube dampers to it from Herbies Audio Lab.  You might want to try them on your Lampizator DAC.

Robert

kernelbob

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Re: too much gain
« Reply #31 on: 22 Aug 2017, 12:54 am »
I'm not sure if this was explicitly mentioned, but LDR's are not solid state.  They are just resistors whose impedance changes depending on the intensity of light shining on them, hence Light Dependent Resistors.  The LDR unit is a sealed unit that contains a resistor and an LED.  The signal path consists of one LDR in series and one LDR shunt to ground.  Balanced units have this arrangement for each phase of the signal.  For the LDR1B, that's it.  For the LDRxB, there's an additional LDR in series of each input.  So, there are no active devices in the signal path, no transistors, no tubes, no opamps and of course no potentiometers or switches.

Shredder

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Re: too much gain
« Reply #32 on: 22 Aug 2017, 01:46 am »
I really appreciate the information. Sounds like I need to give this option a try. As you suggest, I am finding it a bit hard to imagine a pre at this price point outperforming the much much more expensive Cary. I guess i need to get over that.

That is quite the system you are putting together. Which Von Schweikert's do you have? One of the two or three best systems I have ever heard was VS' second from top of the line with VAC electronics.

Take care.

Shredder

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Re: too much gain
« Reply #33 on: 22 Aug 2017, 01:58 am »
From looking at the Tortuga website, it looks like I should wait until V3 comes out to demo one. Any idea when that might be?

kernelbob

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Re: too much gain
« Reply #34 on: 22 Aug 2017, 02:56 am »
Shredder,

I don't know when V3 is coming out or what the features and pricing will be.  Give Morten Sissner at Tortuga a call, he's a great guy to work with.  I'm probably going to get my LDRxB-V2 upgraded to V2.5 at some point, but I also want to see what's going to be in the V3 package.  If you do try the Tortuga, play with various input impedance settings for your Lampi.  Since you're looking at a balanced system, ask Morten about the absolute phase inversion option.  Lastly, you want the hookup wire upgrade.

Regarding my speakers, I have the VR100XS system with towers in the front and XS15 subwoofers in the rear.  Mine are finished in piano black as were the ones you may have seen at the shows (and as are shown on the VSA website).

Robert

kernelbob

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Re: too much gain
« Reply #35 on: 23 Aug 2017, 04:46 pm »
Shredder, I looked at the Cary site for your SLP-05 preamp.  A "cinema bypass" mode is referenced which should bypass the built in volume control.  If you do try the Tortuga, you might want to compare running it as a standalone unit (the way I have mine implemented) and also as an input volume control ahead of the Cary using that cinema bypass setting.

That way, you would basically be using the Cary as a tube buffer.  Using the Tortuga alone offers simplicity, fewer switches (none), and fewer connectors/cables.  Using the Tortuga into the Cary (as a buffer) adds more complexity, connectors, cables, but the tube buffer follower may provide more optimal impedance for the Tortuga to see.

I suspect that you will like the purity of the Tortuga alone and you may get a wider/deeper soundstage.  Soundstage is one area where the Tortuga trounced my ARC REF3.  Same for purity, air, openness, instrumental timbre.  I was surprised when the Tortuga improved bass articulation and extension to lower frequencies which I wasn't expecting from a passive controller.  I haven't tried a Tortuga tube buffer in my system, so I don't have direct experience with this comparison.

Best,
Robert

leftside

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Re: too much gain
« Reply #36 on: 23 Aug 2017, 05:37 pm »
Hmmmm, very sad as I love the Cary. I always gravitate toward tubes and am somewhat hesitant to go a different route. Perhaps the tubed Lampi and warmish Modwright suffice. And, if this really is a mismatch, I assume I am losing much of the benefit of the Cary.
My preamp is a tube preamp. It's a McIntosh C500T.