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Mini Torii SE Amplifier (Read 34538 times)
Raduschka
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Re: Mini Torii SE Amplifier
Reply #100 - 04/06/12 at 01:31:33
 
I have an even more burning question: my current attenuators are already too loud at the 1st step!! Can you please suggest a resistance value that i should be looking at that might allow several steps before I get to the comfortable volume zone? What should I be looking for? Any quality  mono attenuators out there? Thank you very much
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Rivieraranch
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Re: Mini Torii SE Amplifier
Reply #101 - 04/06/12 at 02:48:44
 
Erik6Y6:

By the way, when you have the 6Y6 tubes in the amp it runs hot as hell. The chassis and everything is a lot hotter to the touch as well.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #102 - 04/06/12 at 03:15:49
 
I apologize for interrupting the ongoing discussion.
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Lon
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Re: Mini Torii SE Amplifier
Reply #103 - 04/06/12 at 03:59:47
 
Ah Rad, as the great Monte Negran genius Nero Wolfe would say, "PFUI."

:)

Good to see you posting sir.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #104 - 04/06/12 at 04:03:33
 
why would he spy for the Austrian government??:-)
glad you are still alive
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #105 - 04/06/12 at 20:56:03
 
Rivierafarm

Yah, gotcha.  You mentioned the heat before.  As mentioned, I can add a dedicated filament transformer good for 3A, as well as drop the B+ on the plate if needed for the 6y6.  Heavy current pull by filaments is probably a main source of heat.  All of these changes are exceedingly simple for me to do.  Thanks again for the heads up.  No worries.
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Les Lammers
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Re: Mini Torii SE Amplifier
Reply #106 - 04/06/12 at 22:00:16
 
Radushka wrote:

"I have an even more burning question: my current attenuators are already too loud at the 1st step!! Can you please suggest a resistance value that i should be looking at that might allow several steps before I get to the comfortable volume zone? What should I be looking for? Any quality  mono attenuators out there? Thank you very much "

Are you using a 12AT7?
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #107 - 04/06/12 at 22:15:16
 
hi, I am using 12au7 as input tubes. The volume pots are 100k. I am wondering if I can change that value in order to get what I want or is there an easier way...
I found these, they come in 50k, 100k and 250k if I recall correctly:
http://www.partsconnexion.com/product20925.html
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #108 - 04/06/12 at 23:09:36
 
Radu

A good way to solve this problem is not so much to use a lower value potentiometer -- that may help, but probably mildly, at least that has been my experience in the past.

Parts Express also sells in-line attenuators that essentially offers series resistance, knocking the sginal down by say 6dB or 12dB depending on the one you need for appropriate use of your volume pots.  These really work quite well. As a mattermof fact, I think I have a pair of 6dB attenuators you can have for the cost of your address Smiley.  They look like long RCA plugs (2 inches or so), and can be installed on the amp or preamp/source end -- in this case, probably the source since the jacks on the M T are on the top of the chassis.  Alternatively, you can use a fixed 100k ohm resistor in-line with the signal going into the inputs to the volume control.  If memory serves me right, 100k, which I believe is the value of the pots on the MT, will bring the signal down by about 6dBs or so.  Happy to help if you have questions.  The mini torii is an awesome amp, but some of these modifications can't be solved without mild, rather simple, changes to the circuit.  None of these change the overall character of the amplifier, so the work at Decware and essential voicing of the amplifier remains complete.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #109 - 04/07/12 at 00:17:15
 
thank you all!!!! I think that would be a good way to go Erik2a3, but I cannot use the external attenuators for lack of space. My interconnects are hardwired into the dac and they are the exact length to the top-mounting rca on the mini torii (it was an error), so I cannot add absolutely anything btw them and the rca. Very sweet of you to propose mailing them to me!!!
So I am thinking the following: rather than install extra resistors in the signal path, isn't it possible to reduce the output of the DAC by swapping some already exising resistors in the analog board? Heere is a schematic of one DAC channel, I am not proficient enough to think any further, but perhaps you can have a look and suggest a different value for any of those resistors? Thanks
http://www.flickr.com/photos/71648043@N02/6905930510/

ps: w35 is where it goes out to the amp, just in case it helps to know...
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #110 - 04/07/12 at 00:35:29
 
Hmmmm...

Instead of changing the output voltage of your DAC, as an initial experiment to see how the attenuators work you could use the inline attenuator as the means by which you add perhaps another meter length of IC to give you both some extra flexibility in terms of placement of components, but more importantly, get the added benefit of lowering the gain into the amplifier.  Do you understand?  What you would do is first disconnect the IC going into the amp.  2: plug the ends of that same IC into the female end of the in-line attenuator.  3: then use a a small, female to female RCA adaptor(which are used for adding one length of interconnect to another) on the opposite ond of the attenuator. 4: now take the remaining interconnect -- perhaps only a foot or so is really needed -- and connect one end into the remaining female end of the adaptor/attenuator combination, and the other end into the Mini Torii.  This sounds involved, butnit is very simple and should work fine.   If the connectors are of decent quality it will work exactly right.  In effect, you are just adding some length to your IC.  This would be much easier than changing your DAC outputs, which would actually achieve the exact same thing as the added resistor I mentioned inside the mini torii, only the resistance is further downstream.  Do you see?
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Les Lammers
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Re: Mini Torii SE Amplifier
Reply #111 - 04/07/12 at 01:03:50
 
Eric,

Is the volume control 'hair trigger' with your speakers? I have a 2.5 volt DAC and for got to ask Steve about this being a possible issue.
Been there before.

Les
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #112 - 04/07/12 at 01:27:26
 
I see how adding a resistor right before the volume pots or right at the exit of the dac is one and the same thing. I am convinced that that kind of attenuating method would do exactly what it promises to do. I was just wondering if perhaps there is a more direct way of lowering the dac's output voltage. I asked Brian of AudioNote too. My first step will probably be to buy a pair of 48 step mono stepped attenuators, either 100k or lower (although I do not know yet what the implications of going lower are). If I find that, again, in a few steps I reach max listening levels, I will proceed with the other kind of attenuation. Thank you, you have been most helpful!!!
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #113 - 04/07/12 at 01:35:44
 
Florida boy

No.  But they are pretty sensitive with headphones.  I'm using it with a squeezebox right now for headphone use.  I had the squeezebox output fixed, full volume, but altered the settings so that I could adjust the SB output to about middle range.  Leaving it in that position, I get good control using the pots on the Mini Torii.  But, even with the La scalas I had reasonable volume control without having the slightest rotation blow the walls down.   Just not sure of this particular situation.  It may be that changing the volume controls to something like 10k ohm might help.  If one can get away with that value ptentiometer, there are extensive tests I've read about in journals that indicate improved hogh frequency response with say 10k ohm potentiometers vs those in the range of 100k, 250k, .5meg, etc.  (I'm still struggling with typing on this ipad!). Hope you all are enjoying a nice Good Friday!
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #114 - 04/07/12 at 01:48:24
 
Radu

I know it seems sort of counter intuitive, but the lower the value of control, the LESS sensitive the control is.  Higher values like 100k or 250K present a higher impedance to the incoming signal, which means things will be more sensitive (louder) with the higher value.  The other issue that comes into play with the lower impedance, such as would be the case with a 10k control, involves the relationship between the source output impedance and the new, lower (10k) input impedance of the mini torii, which, depending on the rotation of the VC (volume control), will likely be even lower.  So, if you have a high source impedance going into an overly low amplifier input impedance, there is a chance of poor coupling between the two.  The usual result is reduced high frequency response, and overall poor performance.   Can you tell me what the output impedance spec pf the DAC is?  Also: is there a chance you can change the hard wired IC back into a situation with panel mount jacks?  That would really give you some more flexibility.

BTW: the general output/input impedance ratio is considered good if in the range of 1 to 10.  So, for example, if the output impedance of your DAC is 1kohms, the minmum suitable input impedance (established by either a fixed grid leak resistor or variable volume control) would be 10k.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #115 - 04/07/12 at 01:51:59
 
I am trying to find out right now!
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #116 - 04/07/12 at 01:53:15
 
it is 1.3k!
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #117 - 04/07/12 at 01:56:07
 
so I should be safe with a 20k stepped attenuator, with possibly better highs but steeper taper slopes?

smeeper staple flops

yes, good night everybody and happy Good Friday, you have been good to me and I thank you once more
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #118 - 04/07/12 at 03:40:44
 
Florida Boy,

I understand the M-T comes stock with a 12aU7 (low-gain) driver, which should help with the highish DAC output voltage (my USB/DAC is also 2.25 V).  

According to specs, a 12aT7 will have the M-T reach full power on 1 Volt input (clipping after half a dial of volume pot at 2.0 V input), so since the 12aU7 is significantly lower gain, the full power should be on the 2+ V mark (i.e., clipping with volume pot well beyond half dial).  

This ought to allow some leeway with volume control before max power with DAC outputs above the 2.0 V mark, like in our case.

Of course, this is just my interpretation of the specs.  Let's see if someone more versed in this matters can confirm it.  

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Raduschka
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Re: Mini Torii SE Amplifier
Reply #119 - 04/07/12 at 03:59:22
 
my dac puts out 2.5V (rms?) . I use 12au7 as input tubes and by the 2nd click out of 9 total clicks on the volume pots I start feeling uncomfortable because it is too loud for the neighbours, although it still sounds great. Any position btw the clicks is hard to dial in and maintain.
....
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #120 - 04/07/12 at 04:23:12
 
It may get relatively loud soon (depending on your speakers' sensitivity and room size), but the question is how far from the clipping point it really is.  This does not resolve the volume sensitivity you are already experiencing at 2.5V input, I suppose, but I was hoping the 12aU7 would help keep things in control.  

I know the 12aU7 is 20 Mu's only, compared to 60 Mu's for the 12aT7 (12aX7 is 100 Mu's).  The higher the Mu rating, the higher the gain imparted to the circuit.  There may be other variables involved in this that I'm not aware of, though.

However volume sensitive the M-T is at an input of 2.5 V, it would be even worse with the 12aT7, other things being equal.  Yet, people here report successful results with 12aT7 in place, so there must be some other variables in play?
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #121 - 04/07/12 at 04:27:26
 
I am a total amateur, Erik will know much more about this, but in my MT there is a 2k7 resistor btw the volume pot and the input tube. Can that play a role in this?
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #122 - 04/07/12 at 04:44:13
 
It may, but this design is supposed to work as it was built, accommodating a range of output and driver tubes to skew its performance to meet particular conditions and tastes, by replacing specific tubes and not altering the circuit's basic design.

So, there must be something in the step volume attenuator circuit (if yours is a mod over the original volume pot), that is somehow short-circuiting the gradual attenuation into a bigger step (jump) than expected.

Don't take my opinion as technical, as I'm an amateur like you.  But I would try to see where in the dial the amp is actually clipping, and you'll realize whether there is a problem or is just a relative loudness perception issue.

Let's see if Erik or Kevin can give us some light here.  

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Raduschka
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Re: Mini Torii SE Amplifier
Reply #123 - 04/07/12 at 04:48:22
 
original pots here. I had the same volume issue with my CD player. My speakers are self made AudioNirvana 10 inchers, I think 98 db sensitivity, but I can't confirm that.

anyhow today I finally replaced the resistor that was causing a hiss and crackle phenomenon in the right channel, so I feel like I deserve the Nobel price for electronics Smiley
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #124 - 04/07/12 at 04:53:27
 
Good for you!  If you have the standard volume pots, then I'm at a loss.  Can you try to find the clipping point in that dial (without having to be expelled from the neighbourhood)?  It may well be your speakers' ultra sensitivity (anything above 96 dB is ultra sensitive for this amp).
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #125 - 04/07/12 at 04:58:18
 
they should be thankful for a Nobel price in the neighbourhood.
I cannot really go there volume wise though...

but second click, that would be around 9 o,clock, off the top of my head, is already too loud, yet clear and manageable. i don't think I ever went past the 2nd click. I still do not understand clearly what I must do, but I am convinced that a high quality step attenuator will give the amp a new life. I just don't know yet if they should be 10k, 50k, Dact, Khozmo, Goldsmth, yadda
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #126 - 04/07/12 at 05:05:05
 
A preamp or ZStage may help you ride the gain also ... Control the max volume through a second device, allowing for better dynamics.  Just a thought.  Or a DAC with built-in output control.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #127 - 04/07/12 at 05:10:06
 
I'll see how it goes with an attenuator. If the first steps are any use I can live with a steep gain. If my favourite volumem level is somewhere between those clicks I am going to have to install a resistor somewhere before the atts or lower the output of the dac somehow, maybe directly in its circuit. I am waiting for Brian of AudioNote to illuminate me on that plan. I am off to bed now! Sleep tight!
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Les Lammers
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Re: Mini Torii SE Amplifier
Reply #128 - 04/07/12 at 11:49:37
 
"I am a total amateur, Erik will know much more about this, but in my MT there is a 2k7 resistor btw the volume pot and the input tube. Can that play a role in this? "

Radushka, I would call Decware. There should be an easy way to reduce the gain. Parts Connexion has a good selection of attenuators.
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #129 - 04/07/12 at 12:10:04
 
Good morning, raduscha

That 2.7k resistor on the input to them12AU7 is in a position thatmis sometimes referred to as a 'grid stop' or grid suppressor resistor.  These are also sometimes used in the output stage. Common values are in the range of say 1k to 10k ohms or so.  There usual function is totally unrelated to gain issues.  They are are used to help sort of 'calm' a circuit that may otherwise exhibit high frequency parasitic oscillation.  Almost all of my amps use them.  My Moth Audio si2a3, which we purchsed in the form of a chassis, schematic, and box of parts, uses just such a resistor on the input stage.  In this case it's a common carbon comp resistor where the one on the mini torii is a metal film.

In any event, the output impedance of your DAC is a little high-ish, but not extraordinarily so.  The 100k of the mini torii should be well within a suitable range for it in terms of impedance matching.  Fireblade is right, however, that the higher gain 12At7 can effect this to an extent, but you aren't using that tube.  An impedance buffer could be used, I suppose, and you might try it for curiosity, but you may or may not be interested in adding additional circuitry.

Truly, the common cure for this situation are the in-line attenuators I mentioned above.  I am very picky about what I hear in terms of wanting good detail with requisite bite to the music, and I did not find the attenuators to roll off high frequencie, to cause noise, or anything else.  They just bumped the signal down a bit.  

Another part of this we haven't talked about yet has to do with the sensitivity of your speakers.  Sensitivity and efficiency are not the same thing thing, which is why an input voltage spec in the range of a bit over two volts (sensitivity) is listed in conjunction with the efficiency rating (dBs with 1 watt at a meter).   Based on your description, your speakers likely have a very simple, low order crossover, such as a 6dB per octave slope, which in a two way system consists of only two elements: a capacitor in the high pass to the tweeter and an inductor in the low pass to the woofer/mid bass driver.  If this is the case, a low order network like this presents a low insertion loss to the signal from the amplifier, which means that things will get loud more quickly than they would with a more complex network.  More sensitive still, are single driver, crossoverless systems like Lowthers, Fostex, etc.  the MT sounds beautiful with our 15 ohm crossoverless lowthers, but the mini torii is a better match for the equally efficient Klipsch La Scalas -- an extremely fine match, actually, and I spent a long time listening to this combination yesterday.  I also tried a 12at7 as the driver, and in our second listening space it proved to offer some real excitement.  The 12au7 is far better for headphones, however....

Please let us know how things progress!
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #130 - 04/07/12 at 12:13:24
 
Forgot to mention those grid stoppers are also very often used to help provide immunity against RFI, and I first used them because we live in an area plagued by nearby high power transmission antennas.  I found an even better cure for this problem, though....
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Les Lammers
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Re: Mini Torii SE Amplifier
Reply #131 - 04/07/12 at 12:36:13
 
Erik,

Thanks for your input on the Klipsch. I had the same issue Radushka has when I was driving La Scalas with 300B's and a pre amp that had too much gain. I believe his speakers are single drivers with no crossover in a ported enclosure.

Les


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erik2a3
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Re: Mini Torii SE Amplifier
Reply #132 - 04/07/12 at 13:16:22
 
Florida Boy -- the Audio Nirvana ....yes, you're right.  So often, one can get by without the additional gain of a preamp for that very reason.  Many high sensitivity, high impedance amps only need a pretty small drive signal less than a volt, to get them up and running, in fact where the output of the source is more than enough to push the amp into clipping.  I've paddled in the same boat as both of you, and actually have one foot in it now with our Lowther horns being driven by 300 B monoblocks.  Here's my situation: I use both systems side by side but for different music genres.  The Lowthers horns, which are hugely efficient and of course sans crossovers, are being driven by the 300Bs, which in tuen have a solid state preamp in front of them.  This preamp was an unbuilt NOS Dynaco PAT 4 kit I came across and HAD to have.  It's a preamp that I have always liked, despite its vintage, and had the opportunity to put together myself in the way I prefer.  I has tone controls and a treble roll-ff switch that I use in very small amounts, and give music a very nice sharpness and fast transients where and when needed. But, the gain is a little on the high and sensitive side but acceptable.  I may throw in those attenuators I mentioned to Raduscha, but have just been enjoying the sound so much I haven't bothered.  I also have a valve preamp consisten of a quad of 6sn7s I made probably ten years ago (scary!), thatnis good, but doesn't posses the sharpness and detail I like-- probably 'cause my ears are older and I can't hear as good as I used to! Shocked
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #133 - 04/07/12 at 13:31:39
 
Raduscha

Something else: intalling a 10k linear (rather than log or audio taper) pot (trim pot) on the output of your DAC, therby allowing you to fine tune the gain into the amp.  This is not unlike what Fireblade mentioned, but withput the extra circuitry and power supply elements of an impedance buffer stage.  I'm sure you know this already but the 'Z' in Z-box is a designation of impedance.  As in: output Z  is shorthand way of referring to output impedance.

Edit: I hadn't read through all of this before responding, but Firblade did mention the output control on the DAC or a preamp.  Both excellent ideas!  I think he has great thoughts on this.  The amplifier dual pots could be used to balance and adjust the iput level into the mini torii and use the volume control on preamp as the general purpose control.  Just leave the M. Torii pots set.
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Re: Mini Torii SE Amplifier
Reply #134 - 04/07/12 at 13:42:40
 
Ok -- lastly!  Sorry, ideas keep coming to me.  Some vintage amps had potentiometers on the input into the amp so that high level and low level source signals could be matched more closely.  On the MT there are two additional holes near the binding posts that could be used for input gain pots.  These would attenuate the signal before going to the selector switches and volume control.  Again, 10k might be a good value to try, however the hole are for mini switch shafts, and might need to be drilled if a larger pot were to be used.  Just an additional thought.........
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Les Lammers
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Re: Mini Torii SE Amplifier
Reply #135 - 04/07/12 at 14:08:26
 
Erik,

No xover to suck power and a 2.5v source is the issue. I think a call to
Decware will be Radushka's best bet. I think I will be OK using  12AU7's. I am having my Mini built with a stereo volume pot and think I will purchase a very good quality one and send it to Deware to be installed. I am leaning towards using Takman carbon resistors and Audio Note copper foil caps and may send them to Decware with the attenuator. I have plenty of time to decide.

Happy Easter all,

Les
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #136 - 04/07/12 at 14:30:47
 
Jesus and Mary, I managed to sleep well despite the whole obsession with trim pots and atts! I see you've been thinking while I was asleep Smiley  
Yes, my AudioNirvanas are fullrange inside ported cabinets, as Fireblade pointed out, so no crossovers there.
From what I understand, if the output Z of my dac is 1.3k I should be looking at a 20k or maybe 50k attenuator? I take it seriously when you say, Erik, that lower impedance pots have a better impact on high frequency reproduction. I read an article yesterday about how important a good quality volume pot is in a preamp and so I am all worked up about getting a dact or smth similar. I am willing to try those attenuators you mentioned, if you 'promise' they won't confront my purist mentality Smiley I can pm you my address and perhaps send you smth good from Montreal in return, maybe smth to eat??
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Fireblade
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Re: Mini Torii SE Amplifier
Reply #137 - 04/07/12 at 19:27:33
 
I'm afraid now I may confront the same problem: My speakers are the DM945's (no cross-over, 94dB) and my USB/DAC is a highish 2.25V output.  What I don't understand, is how come people using even the 12aT7's as input drivers and with sensitive speakers, still find the gain manageable.  

Theoretically, the M-T is supposed to accommodate for all these variations in driver and output tubes for sources ranging from 1 to 2 V, without issues.  For example, with a 12aT7 and sensitive speakers (94-98 dB), the volume pot may reach full power at mid-dial using the stock 6V6 output tubes for typical sources @ 2 V.

Following this reasoning, someone using 12aU7 drivers in these same conditions ought to be able to go at least half dial before clipping, with source signals beyond the 2.0 V mark.  The driver's lower gain should compensate for the extra input voltage, making the setup gain profile still manageable.

Evidently, there are exceptions to this, as has been described earlier.  Anyone has a clue?  Should we prepare ourselves in advance to cope with this potential problem?  How? We'd be hard pressed to find good DACs with lower output signals than the typical 2 V.  Is the M-T condemned to be used either with an iPOD or other low output source and/or the application of a high quality volume step attenuator mod?

I'm just trying to see if I may confront this problem when my gear arrives, and to prepare myself in advance with a potential counter-measure.  Thanks for your inputs.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #138 - 04/07/12 at 19:32:55
 
Fireblade,
remember that in my case we are dealing with appartment friendly levels, so I don't have a clue where my amp clips. My initial problem was with how little leeway I have between 0 and the first click and how hard it is to make the pot stay in place btw clicks. So in my case the second click is already too loud.
BTW I think my AudioNirvanas inside cabinets are 94 db too, but I better check.
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #139 - 04/07/12 at 19:34:14
 
Floridaboy

What I mentioned about this are the most usual ways of dealing with excessive gain....which I have dealt with over twenty years and from designing and building some of my own amps.  But doubtless you are right that Decware knows more about there products than anyone!  We are  just sharing ideas, which in my view makes for beneficial discussion.

He could also even use a variable L pad on his driver, selected to match the impedance of the same... But yuk, it would be better to take care of it at the line level, if by no other way than by putting a preamp between DAC and amp.
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Re: Mini Torii SE Amplifier
Reply #140 - 04/07/12 at 19:37:11
 
...no way am I buying a preamp Smiley
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #141 - 04/07/12 at 19:38:26
 
I am still caught btw attenuator models... Khozmo, DACT, Goldpoint....
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #142 - 04/07/12 at 19:41:35
 
I have precisely 3.6 mm under the cover of the Mini T to install 2 mono atts. Ladder type.
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #143 - 04/07/12 at 19:55:21
 
maybe i could get one of those diy goldpoint attenuators and choose my own resistor values so that I have a lot of room to adjust the volume between 7 and 12 o,clock? They come at about 150$ for 2xmono (shipping included). Am I deluded?
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Re: Mini Torii SE Amplifier
Reply #144 - 04/07/12 at 19:56:48
 
Radushka,

Even if I have less volume-level listening restrictions, having an extra-sensitive volume pod is not ideal.  I thought I would have at least half a dial to find my optimal volume level.  This may not be the case if the gain is so high, that jumping from one of the initial clicks to the next, misses the intended volume target altogether.

I have not heard about this problem before (with the M-T), so I guess in most cases is still manageable.  But then again, my DAC is 2.25 V. Sad
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #145 - 04/07/12 at 20:02:01
 
yes, I agree it is a problem, even in my case, I was just suddenly afraid I had exaggerated it, but I hadn't. So seriously, if I am not completely off the mark I will buy 2 mono atts from Goldpoint's ebay site and colonize them with my own choice of fancy resistors from PartsConnexion. And I don't even need high volumes!!!! When I move into a huge house with passive solar design, inspired by Mies von der Rohe, I will take them out and add new resistors.
Plus the Goldpoints fit nicely under the hood.
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #146 - 04/07/12 at 20:43:59
 
What is your source...what is feeding the DAC?
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #147 - 04/07/12 at 20:46:30
 
a Cayin cd t15 tubed output cd player. used as a transport only of course
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erik2a3
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Re: Mini Torii SE Amplifier
Reply #148 - 04/07/12 at 21:08:42
 
Does it have analog outputs?
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Raduschka
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Re: Mini Torii SE Amplifier
Reply #149 - 04/07/12 at 21:10:47
 
sure
I had the same issue with those (2 v I think) But I can't remember if it was slightly better. I could try later on, I gotta go out, eat some sushi with my girlfriend.
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