VA1 and Avita in small room

Myriad,
Definitely your room is toooooooooooooooooo big for VA-1. I have heard them in a similar sized room and instantaneously I felt the lack of power. In a small room it will definitely sound much better. But I still doubt if it can bring out the dynamics and big-ness of your solid states.. . I just didnt find the VA-1's presentation to be Grand and all that. Though it definitely is a very smooth and resolved amp.

abhi.pani schrieb:

Myriad, Definitely your room is toooooooooooooooooo big for VA-1. I have heard them in a similar sized room and instantaneously I felt the lack of power. In a small room it will definitely sound much better. But I still doubt if it can bring out the dynamics and big-ness of your solid states.. . I just didnt find the VA-1's presentation to be Grand and all that. Though it definitely is a very smooth and resolved amp.

What a lovely room - I would kill for a room of this size;
Not to forget a room to spare !! Lucky you !!!

Yes, the VA-1 is just not enough for a room of that size. 410 sq. ft. is double of what is needed.

What you need is an ARCA + Canasya [speaker + amplifier]
However, your chain is not up to that level, so I guess you will not spend that much more.

The Cadence has a house sound, either one likes it or one hates it.

What a lovely room - I would kill for a room of this size;

Seriously...he is lucky
But the downside of such a big room is also evident...you need a much more powerful setup

The Cadence has a house sound, either one likes it or one hates it.

I dont think "Hate" is the right word. At the max one may not like it as much....but it definitely doesnt have a sound that can be hated

I have read in Audio Asylum people using SS for LF driver and Tubes for ESL panels.
I want to know how they use two different amps for different drivers. Im sure these different amps must be having different impedance and gain.

bhagwan69 schrieb:

abhi.pani schrieb: Myriad, Definitely your room is toooooooooooooooooo big for VA-1. I have heard them in a similar sized room and instantaneously I felt the lack of power. In a small room it will definitely sound much better. But I still doubt if it can bring out the dynamics and big-ness of your solid states.. . I just didnt find the VA-1's presentation to be Grand and all that. Though it definitely is a very smooth and resolved amp. What a lovely room - I would kill for a room of this size; Not to forget a room to spare !! Lucky you !!! Yes, the VA-1 is just not enough for a room of that size. 410 sq. ft. is double of what is needed. What you need is an ARCA + Canasya [speaker + amplifier] However, your chain is not up to that level, so I guess you will not spend that much more. The Cadence has a house sound, either one likes it or one hates it.

bhagwan,

I cannot think of another upgradation right now.
VA-1 sounds divine at low and moderate volumes. It's only when i try to crank a little loud the set up show it's limitation in big room. Whereas Nad couldn't sing at low volume whereas they came to life once i increased the volume. Again one cannot listen for long at high volumes.I know there are trade offs in every design. Maybe i should have ss and tubes for different moods and times

myriad schrieb:

I have read in Audio Asylum people using SS for LF driver and Tubes for ESL panels. I want to know how they use two different amps for different drivers. Im sure these different amps must be having different impedance and gain.

one has to be very careful doing this. Not only do different amps have diff impedance (which should not be an issue for a s.s. amp driving a woofer) & gain but also different tonality which will manifest itself as a separate-tweeter-separate-woofer sound. You might get the oomph from the bass driver but the overall sound will fragmented.
If you are going to do this experimenting with diff s.s. amps to match your VA-1 will be the course of action on your part. Could get tedious!

bombaywalla schrieb:

myriad schrieb: I have read in Audio Asylum people using SS for LF driver and Tubes for ESL panels. I want to know how they use two different amps for different drivers. Im sure these different amps must be having different impedance and gain. one has to be very careful doing this. Not only do different amps have diff impedance (which should not be an issue for a s.s. amp driving a woofer) & gain but also different tonality which will manifest itself as a separate-tweeter-separate-woofer sound. You might get the oomph from the bass driver but the overall sound will fragmented. If you are going to do this experimenting with diff s.s. amps to match your VA-1 will be the course of action on your part. Could get tedious! :.

I tried two different amps in my previous set up and frankly it never worked. Hf & lf driver never integrated. I tried both ss as well as tube and ss combination.
I think, it's better to swap from tube to ss and vice versa for different music and mood.
Can you suggest some good, affordable (within 50-60 k) ss amps to go with Avitas?

How about a Sugden (should be available within 70k) ? Or even a Roksan ?

wonder who sells sugden in India ?

Arj could throw some light on this. I suppose he should be able to suggest multiple ways of getting a Sugden..

myriad....do you have the 20watter or the 35 watter ?

Manek.

bombaywalla wrote: myriad wrote: I have read in Audio Asylum people using SS for LF driver and Tubes for ESL panels. I want to know how they use two different amps for different drivers. Im sure these different amps must be having different impedance and gain. one has to be very careful doing this. Not only do different amps have diff impedance (which should not be an issue for a s.s. amp driving a woofer) & gain but also different tonality which will manifest itself as a separate-tweeter-separate-woofer sound. You might get the oomph from the bass driver but the overall sound will fragmented. If you are going to do this experimenting with diff s.s. amps to match your VA-1 will be the course of action on your part. Could get tedious! I tried two different amps in my previous set up and frankly it never worked. Hf & lf driver never integrated. I tried both ss as well as tube and ss combination. I think, it's better to swap from tube to ss and vice versa for different music and mood. Can you suggest some good, affordable (within 50-60 k) ss amps to go with Avitas?

I concurr with both of you.

I tried to bi-amp my Extremas with the Flying Moles (Solid State, Switching Amps ) feeding the Bass unit and Prima Luna Valve amp feeding the tweeter.

Result - sound worse than if either amp was given full charge of the speakers...

abhi.pani schrieb:

How about a Sugden (should be available within 70k) ? Or even a Roksan ?

Hi Abhi,
Which roksan model are you comparing to the Sugden ? Power / integrated ?

I was talking of Roksan Kandy Integrated...but I am not comparing between Sugden and Roksan....I suppose they are two good choices for that kind of a budget.

http://www.roksan.co.uk/kan_amplifier.html

Kandy is their budget series.
The caspien M series poweer amp is available around the same price……..
http://www.salisburyhifi.co.uk/website/roksan/caspian%20power.htm
Who sells roksan in India ?

Manek schrieb:

myriad....do you have the 20watter or the 35 watter ? Manek.

35 watter

I have Audio Note Dac One 1.1x signature connected to VA-1.
I read a post in Audio Asylum saying that AN Dac 1.1 needs at least 30k ohms input impedance to sound at it's full potential. The VA-1 has 10k ohms input impedance. I contacted Peter Qvotrup through e mail and he too echoed the same in his reply.
Is this mismatch anyway limiting the dynamics?

roksan if I remember right is distributed by marbin colah of innovative systems in bombay.

I like the roksan amps.

manek.

myriad schrieb:

I have Audio Note Dac One 1.1x signature connected to VA-1. The VA-1 has 10k ohms input impedance. Is this mismatch anyway limiting the dynamics?

I am confused;
Your DAC's output will go into the VA-1
so what is the mis match about ?
If the AN DAC needs 30 K input impedence, then that will have to come from your Transport [what ever it is that you use]. How is it connected with the VA-1 ?

Please do shed some light.

Thanks.

abhi.pani schrieb:

I was talking of Roksan Kandy Integrated...but I am not comparing between Sugden and Roksan....I suppose they are two good choices for that kind of a budget. http://www.roksan.co.uk/kan_amplifier.html

The Sugden is far better than Roksan.

Roksan is sold my Mr. Marbin vdH Colah.
I wonder what stock he has.

I would strongly suggest Sugden over Roksan.

bhagwan69 schrieb:

myriad schrieb: I have Audio Note Dac One 1.1x signature connected to VA-1. The VA-1 has 10k ohms input impedance. Is this mismatch anyway limiting the dynamics? I am confused; Your DAC's output will go into the VA-1 so what is the mis match about ? If the AN DAC needs 30 K input impedence, then that will have to come from your Transport [what ever it is that you use]. How is it connected with the VA-1 ? Please do shed some light. Thanks.

AN states that the preamp's input impedance should at least be 30k ohms whereas VA-1's input impedance is 10k ohms.
My dvd player is connected to dac and dac to amplifier.

bhagwan69 schrieb:

abhi.pani schrieb: I was talking of Roksan Kandy Integrated...but I am not comparing between Sugden and Roksan....I suppose they are two good choices for that kind of a budget. http://www.roksan.co.uk/kan_amplifier.html The Sugden is far better than Roksan. Roksan is sold my Mr. Marbin vdH Colah. I wonder what stock he has. I would strongly suggest Sugden over Roksan.

Bhagwan,
How would the Roksan Caspian series or even the kandy power amp compare to a Nad c272 / Advance acoustics power amp ?

Manek,
Which Roksan amp did you listen to ? How would you describe their sound ? How are these priced in India ?

Nad - Advance - Roksan - Sudgen

That is how I would place them.

Many, Many Moons ago, Sushil at PLAY ( then Nova Audio ) handled Roksan.

He gave it up ... felt was too Expensive.

If Im not mistaken, the mid level Roksan Caspian amp was Rs 90K....

I had heard their caspin series amp some time back . donk know if they are really VFM on the basis of pricing.

for the sound quality which is marginally better than the entry level (NAD/ROTEL/MARANTZ) the pricing used to be way off in singapore.

I think they struggle in their bass reproduction with the not so easy speakers, something which is not expected at that price level.

I found the CDP to be pretty nice and delicate though.

they look good though !

Bhagwan, the AN dac needs to see an input impedance of 30Kohms on the amplifier it connects to.

The va 1.0 has 10Kohms input impedance on any line level input socket. The AN 1.1 dac has maybe 2500-3500 ohms output impedance(myriad whats the exact spec?), hence if you go by the general rule of output impedance(source)*10 should match input impedance of amplifier or any other input device.....then the AN would need an amplifier input impedance of approx 30K.

myriad if you could furnish us with the output impedance of your AN dac...we could shed some more light.

Manek.

Manek schrieb:

Bhagwan, the AN dac needs to see an input impedance of 30Kohms on the amplifier it connects to. The va 1.0 has 10Kohms input impedance on any line level input socket. The AN 1.1 dac has maybe 2500-3500 ohms output impedance(myriad whats the exact spec?), hence if you go by the general rule of output impedance(source)*10 should match input impedance of amplifier or any other input device.....then the AN would need an amplifier input impedance of approx 30K. myriad if you could furnish us with the output impedance of your AN dac...we could shed some more light. Manek.

http://www.audionote.co.uk/
Go to Resources and then Dac 1.1x signature.

hi,

I read the specs. output impedance is 2K. 20K of input impedance of the amp should suffice but one never knows.

Myriad, since the VA has only a pot for volume(passive) which is of 10K why dont you ask cadence if they can incorporate a volume pot of 30K or 40K ? Wonder if their design would allow for it ?

Manek.

or maybe you could try out a line stage buffer with a large input impedance and a low output impedance of 50-100ohms to see if it really makes a difference.

Manek.

Manek schrieb:

or maybe you could try out a line stage buffer with a large input impedance and a low output impedance of 50-100ohms to see if it really makes a difference. Manek.

thats a good suggestion as some line stage buffers are just that , impedance matchers (or rather impedance transformers)

Manek schrieb:

hi, I read the specs. output impedance is 2K. 20K of input impedance of the amp should suffice but one never knows. Myriad, since the VA has only a pot for volume(passive) which is of 10K why dont you ask cadence if they can incorporate a volume pot of 30K or 40K ? Wonder if their design would allow for it ? Manek.

That's right. I, too, read the specs on the AN(UK) website & it says < 2KOhms.
I used 2KOhms like you did.
So, if the source has a 2KOhms impedance & the VA-1 has 10KOhms, I calculated a voltage transfer ratio of 0.83.
IF the VA-1 input impedance was 30K, then the voltage xfer ratio would have been 0.9375.
So, I calculate a 1dB loss in signal (vs. the "ideal" case of inp imp of 30K).
IMHO this is not much but it could still be hearable by Myriad.
Loss of bass response & slightly wooly bass is what I'd expect. Somewhat rolled off highs as well.
These aspects are probably not discernable unless a direct A/B comparison is made.

Another suggestion (don't know how practical) is that Jensen (USA) makes impedance transformation transformers. They are very good sounding but expensive.
I like Manek's suggestion the best - to change that 10K vol pot to a 100K volume pot. See if you can get Screamgigi or Viren to do this job for you.

bombaywalla schrieb:

Manek schrieb: hi, I read the specs. output impedance is 2K. 20K of input impedance of the amp should suffice but one never knows. Myriad, since the VA has only a pot for volume(passive) which is of 10K why dont you ask cadence if they can incorporate a volume pot of 30K or 40K ? Wonder if their design would allow for it ? Manek. That's right. I, too, read the specs on the AN(UK) website & it says < 2KOhms. I used 2KOhms like you did. So, if the source has a 2KOhms impedance & the VA-1 has 10KOhms, I calculated a voltage transfer ratio of 0.83. IF the VA-1 input impedance was 30K, then the voltage xfer ratio would have been 0.9375. So, I calculate a 1dB loss in signal (vs. the "ideal" case of inp imp of 30K). IMHO this is not much but it could still be hearable by Myriad. Loss of bass response & slightly wooly bass is what I'd expect. Somewhat rolled off highs as well. These aspects are probably not discernable unless a direct A/B comparison is made. Another suggestion (don't know how practical) is that Jensen (USA) makes impedance transformation transformers. They are very good sounding but expensive. I like Manek's suggestion the best - to change that 10K vol pot to a 100K volume pot. See if you can get Screamgigi or Viren to do this job for you.

First of all, i don't think Cadence will be ready to change the design for me. Secondly, it will cost me almost 8000/- rupees to send the amp from kolkata to Mumbai and back... top of that the cost of pot they will charge.
I think it's better to dispose the dac and go for a standalone player or a dac which is compatible with VA-1.

myriad schrieb:

First of all, i don't think Cadence will be ready to change the design for me. Secondly, it will cost me almost 8000/- rupees to send the amp from kolkata to Mumbai and back... top of that the cost of pot they will charge. I think it's better to dispose the dac and go for a standalone player or a dac which is compatible with VA-1.

Ach, you are based in Calcutta!
According to member Screamgigi there are a number of people in that city who have good soldering skills that will be able to do the mod for you.
If I were you, I would get in touch with member Screamgigi or member Viren & see if you can get a 100K volume pot from them. They DIY build tube amps regularly & the should have this component.
Also ask them for a reco for which outfit to take your amp to get the mod done.
It should be a simple & quick one.

Of course, check with Cadence that doing such a mod is OK/compatible with the VA-1.

You could also dispose off the DAC & get another one that has 100 Ohms or less output impedance.
You will have to audition a few to get a one which suits your tastes.

myriad schrieb:

First of all, i don't think Cadence will be ready to change the design for me.

you presume too much! They are not changing the design! they are making a tweak to your particular unit. All other units in the field + those on the manuf line will be unaffected.

1. The topic of High input impedence is close to my heart and I have been 'researching' its deployment & effect at the Volume control stage...

Bombaywalla's calculations are good, and provide a rational approach to the topic ... to a point.

2. There are second order effects that need to be considered, in an audiophile's perspective.

1. With a simple 1st Order filter that is created ( as in this case) there is not only loss of amplitude ( as correctly calculated by Bombaywalla) but also a phase shift (delay) at all frequencies that suffer some attenuation. The Phase delay reaches ( and thereafter stays at ) 90 degrees at the -3dB freq.

Phase delay means that those frequencies are delayed... substantially delayed... upto a quater wavelength !

The late arrival will cause sound smearing and loss perceived resolution.

Anyways, in this particular case, the loss is tiny, and IMHO negligible. I just wanted to point out the phase delay & its impact, which is almost always over looked.

The same applies to the query a few days ago, as to the benift of a 45KHz capable tweeter. If its -3dB freq is Way beyond 20KHz, it will have negligible phase shift ( sound smearing ) at 20 KHz.

The other comments on more openess and air also hold ... with our without that proverbial pinch of salt....

3. Comming back to the Volume control....

My personal impression is that High Impedances ( atleast 47 K Ohms, preferably 100K ohms and above ) volume controls preserve a sence of air and ambience that low impedences ( below 10K ohms just cant deliver ).

Almost All Valve pre-amps / amp deploy 100K Ohms or higher.

Lower values ontribute to lower noise and better specmanship. Also solid state electronics prefer lower impedences.

4. The Volume contol type & brand also substantially contribute to the overall sound.

Any resonably resolving stereo wil show the difference between an ALPS Pot and a Philips carbon pot... just the way Interconnects sound different.

The Cadence amp does not use the el-cheapo Philips pot, I saw tghat last weekend....

Hence I suspect that Cadence may not be able to swap Pots for you, simply because they may not have stock of a higer ohmic value, in the purist brand that they use.

Check with them, before you pay that huge shipment... ( which equals to the price of a Good DIY DAC ! )


P.S: Sorry for this long sermon / post..

Sorry to butt in guys, but just couldnt resist asking this question.
I am using a Plinius Integrated amp which has an input impedance of 47 kOhm. I suppose the output impedance of my source should be around 500 ohms but I am using a NAD C521 as CDP, which has an output impedance of 300 ohms...does that have any remarkable effect on the sound ? Do I have to look into this issue ?

nope

abhi.pani - you are in great shape, Sir.

If your CDP has an output impedence of 300 Ohms, it will VERY Comfortably ( with practically ZERO performance penalty ) drive any Pre or Power amplifier with an Input impedence of 10 Times 300 Ohms or higher input impedance.

Hence yr CDP will be THRILLED to drive an input impedance of 3,000 Ohms or higher.

47K Ohms is much higer, and therefore will draw even less current from the CDP, so its a Great match.

ENJOY !

Amp_Nut schrieb:

abhi.pani - you are in great shape, Sir. If your CDP has an output impedence of 300 Ohms, it will VERY Comfortably ( with practically ZERO performance penalty ) drive any Pre or Power amplifier with an Input impedence of 10 Times 300 Ohms or higher input impedance. Hence yr CDP will be THRILLED to drive an input impedance of 3,000 Ohms or higher. 47K Ohms is much higer, and therefore will draw even less current from the CDP, so its a Great match. ENJOY !

Without any knowledge of input-output impedance, even I felt that they match really really well...just was curious to know if there is something I was missing
Thanks for the info...buddy.

I was going through archives on Audio Asylum and found this thread on An dac 1.1x.

http://db.audioasylum.com/cgi/t.mpl?f=amp&m=43915

(In Reply to: Re: Preamp Input Impedance and Source's Ouput Impedance? posted by IkeH on April 15, 2004 at 06:00:14:

Dear Ike,
27 kOhm should work OK, but I think you may find that it is possible to just change the load resistors on the CD input to increase the impedance.

Or you could change the output capacitor from 0.47uF to 1uF or slightly higher in the DAC One.1x.

Sincerely,
Peter Qvortrup)

I am not a technical guy so please help me out.
Will changing the output capacitor solve the problem of mismatch and the dac working at it's full potential?

Amp_Nut schrieb:

1. The topic of High input impedence is close to my heart and I have been 'researching' its deployment & effect at the Volume control stage... Bombaywalla's calculations are good, and provide a rational approach to the topic ... to a point. 2. There are second order effects that need to be considered, in an audiophile's perspective. 1. With a simple 1st Order filter that is created ( as in this case) there is not only loss of amplitude ( as correctly calculated by Bombaywalla) but also a phase shift (delay) at all frequencies that suffer some attenuation. The Phase delay reaches ( and thereafter stays at ) 90 degrees at the -3dB freq. Phase delay means that those frequencies are delayed... substantially delayed... upto a quater wavelength ! The late arrival will cause sound smearing and loss perceived resolution. 3. Comming back to the Volume control.... My personal impression is that High Impedances ( atleast 47 K Ohms, preferably 100K ohms and above ) volume controls preserve a sence of air and ambience that low impedences ( below 10K ohms just cant deliver ). Almost All Valve pre-amps / amp deploy 100K Ohms or higher. Lower values ontribute to lower noise and better specmanship. Also solid state electronics prefer lower impedences. 4. The Volume contol type & brand also substantially contribute to the overall sound. Any resonably resolving stereo wil show the difference between an ALPS Pot and a Philips carbon pot... just the way Interconnects sound different. The Cadence amp does not use the el-cheapo Philips pot, I saw tghat last weekend.... Hence I suspect that Cadence may not be able to swap Pots for you, simply because they may not have stock of a higer ohmic value, in the purist brand that they use. Check with them, before you pay that huge shipment... ( which equals to the price of a Good DIY DAC ! ) P.S: Sorry for this long sermon / post..

Amp_Nut, thanks for the explanation of the 2nd-order effects. I had not considered this aspect. You make a good point of phase shift due to the 1st order filter. I shall keep this in mind the next time I encounter low impedance inputs to a power amp.

Amp_Nut schrieb:

The Phase delay reaches ( and thereafter stays at ) 90 degrees at the -3dB freq.

do you think that this is correct?
Somehow I remember 45 degrees of phase shift at the -3dB corner & 90 degrees at 1 decade above the -3dB freq.
A 1st order filter has only 1 reactive component (L or C) & hence only +/- 45 degrees should be possible.

changing the load resistor on the cd input of the amp would do it, i think.

Scream, viren, siva, amp_nut....what do you guys say ?

manek.

do you think that this is correct? Somehow I remember 45 degrees of phase shift at the -3dB corner & 90 degrees at 1 decade above the -3dB freq. A 1st order filter has only 1 reactive component (L or C) & hence only +/- 45 degrees should be possible.

You are 100% Correct Bombaywalla.

My knowledge was rusty.

Thanks for the correction.

Manek said:

changing the load resistor on the cd input of the amp would do it, i think.

Yes, Manek.

I think that integrated amp has a passive pre amp section ? I am not sure..

If it is a passive preamp, then the input goes directly to the Volume control pot, through the input selector switch.

In such a case an 1 SERIES resistor at the Hot point of the CD input for each channel.

Will not cost more than Rs 1 x 2.

You will have to crank the volume control knob higher up, after the series resistor, but that should not be a problem, sonically.

BTW..i want to ask...
is it always the load resistor on the amp inputs which determines as the input impedance of a power amp ? Would changing load resistor affect the sensitivity of the amp by any chance ? Can this mod be done to all amps SS and tube to get the desired impedance value ?

Manek.

A few points :

1. The input (impedence) resistor is usually referred to as the resistor in parallel at the input of the amplifier. Parallel - ie between the signal terminal and ground.

2. The effectice input impedence of the amplifier ( that is what the source will see ) is the sum of the amplifier's input impednce + the external resistor.

3. For Valve or JFET inputs the amplifier's input impedence is usually Very high ( atleast a few Hundreds of K Ohms ) and so the external resistor practically determines the input impedence of the amp.

3. For SS ( BJT) amps the amplifiers input impedence itself is not too high ( often less than 100K ohms, so the external resistor + Amps intrinsic input impedance come into play.

4. Ther external resistor , particularly in SS amps can change ( usually degrade) :

i. The amplifier noise

ii. The Output Offset at the speaker terminals

iii. SOMETIMES, the stability of the amplifier. Instability can result in more noise, and / or a harsher sound , and /or the tweeter blowing !

Hence dont take it for granted, and dont change the input resistor at will...

Ofcourse, iii. above is me playing the devils's advocate... a worst case senario.

Whooo, what mastery over the technical aspects of HiFi !
BTW, Amp, did you buy the SFE spkrs in India?
Where & how much?
Kamal

Hi Kamal.

Thanks for the kind words...

Yes, I did buy the SFEs in India ... Pre-Owned ( that is a nice way of saying 2nd Hand ! )

Bought them about 2 years ago, with stands for Rs 1,00,000

I am told a pair (Pre-owned ofcourse) is available with the SF dealer in Delhi, but the seller is asking for Rs 2 L.

thanks amp nut.....for the detailed explanation.

manek.

bhagwan69 schrieb:

Nad - Advance - Roksan - Sudgen That is how I would place them.

I have a Nad 214 power amp.
How about coonecting a tube pre with Nad?
Has anyone tried the same combination?