Tweak,
I would think that a magnetic material such as steel would not be ideal for placing around crossover components, especially air-core inductors. That would definitely interact with the magnetic fields produced by the inductors, in unpredictable and probably deleterious ways. Non-magnetics would be preferable IMO. |
Ait
I wondered who would post first about this catch point. I agree... this was an experiment based on effects of damping and their side effects. All of this was done 8 or so years ago. Since then we use brass shot as the fill material around the conductors. Still overdamping can be expected with the non ferrous materials as well. Try removing the ferrous cover from your AC mains and hear what happens. Bends the fields of flux? Tom |
Sorry to interupt the resonance dampening discussion.
As I had mentioned long ago I am still very intrigued by why the recording process improved till the late 60's. As much as I have enjoyed the Duelund parts they clearly reveal that the recording process is just as important. The recordings using tube mixers and (likely foil caps) and Nueman U47 mics sound fantastic! I have read that Frank Sinatra would walk out of the studio if they did not have a "Teley" (relabeled Nueman) tube mic. |
I have been doing some digging into the Neumann U47 tube mic. (regarded as the Holy Grail of mics)
These are known as capacitor mics. Funny thing it is tough to find out what kind of caps they used? Guys go about rebuilding them and give great focus on the $2k vintage tube etc. and treat caps as not important.
I find MUCH more difference in caps than tubes? Yes there is a difference in tubes don't get me wrong. I do not mean to upset tube guys.
One thing I will bet on with this sought after mic that those caps DO matter. I have heard many say that there is a huge variance in the U47 well no doubt if the caps are changed in such a crucial component as the mic you are going to hear it! If the mic messes the sound the whole chain is done.
I did read one guy claims to have reproduced the sound using silver foil caps. Well at least I can understand that.
There is 3 caps and 8 resistors in the mic and no one can clone it? (I bet money it is the caps or caps resistor combo)
They mentioned paper in tar??? Could that be part of the U47 sound???
Funny in the thread the guy mentions using modern Audionote, Auricap, Mundorf or "maybe even a Duelund if it could fit" Now that I would like to hear! I have yet to hear as good a vintage cap.
It could be possible to better the U47 mic.
Duelund you really need to get these parts in commercial products. I would be thrilled! |
Volleyguy,
So would I - ;) |
Duelund
The thread mentioned paper in tar caps. I have not heard of that but can see the sense in it for dampening. Anyone heard paper in tar caps??? |
Tar did not prove successful in our testing. |
Duelund
Hmmm you did try tar? Are turning over every rock for better sound?
I am waiting to see on partsconnexion your Rev II wire. Any idea when it is coming out?
Jimmy is trying your resistor in his pre-amp? I thought they were just for speakers? Should be interesting!
I was reading in Stereophile about the Hi-Fi show in Munich about the Korean businessman (Silbatone) who brought in a set of Western Electric speakers (not for sale) and many thought them the best in show. Anyone hear them? |
That's what we do I guess. With your own impregnation and winding facility, we are afforded many options.
Rev II wire is available now.
Some clients use our resistors for amps as well. |
I checked on partsconnexion and the website is not updated?
What is Rev II wire and is it just Silver or copper as well? Is the price the same?
I will for sure be following Jimmy's thread on the resistors. I have not tried any Duelund resistors as my crossover does not have any resistors. |
For electronics the Texas Components Z-foil TX2575 resistors will be very hard to beat. I use them extensively in my system and they are incredibly clean and clear sounding. Much, much easier to fit into electronics than the Duelund resistors (which I do use in my crossovers, by the way). |
Ait
"For electronics the Texas Components Z-foil TX2575 resistors"
Yep they are pretty incredible, I used them where they would really count in a phono stage loading the cartridge directly, and for the gain setting... Huge difference in frequency response and transparency. Similar to using a duelund resistor in the speaker which again is not seeing a full range signal, but even much more note worthy in electronics for sure as this really shows full effect.
I belive they are no longer Texas instruments, but now under the Vishay "Naked Z" series.
However for the price you could go broke in no time trying to do a whole preamp or amp. I would just go with them in really critical signal paths and they have great effect. |
The Z's I used to replace a few of the Dales's in the Wyred4 Sound preamp volume control.. select values that are in my normal listening range made for a vey nice improvement in noise floor and transparency. Plus there are ones that are always engaged in the signal path those too were swaped out for the Z's. I have also replaced the non inductive wire wounds in my poweramps with the Duelunds making for the same type of improvement as the preamp. Tom |
Undertow, Texas Components is a manufacturer in Texas which makes their own resistors using the Vishay Z-foil (part # TX2575). I just ordered 4 of them yesterday. Just call them and order whatever you want (1 part minimum!), and they will make any custom value you need for no extra charge. http://www.texascomponents.com/. |
AIT, how are their prices compared to PC?
Thanks,
Mike |
Volleyguy,
It is no fault of our dealers. Becoming a father 3 months ago has meant I'm behind with quite a few undertakings. I've recently begun getting sleep at night again, so I'm doing my best to get everybody including myself up to speed. |
Texas Components prices are much cheaper than PC. I payed $9.40 each for the ones I ordered this Monday. |
IMO TX2575 is unsurpassed and make a difference almost everywhere they are used as budget permits. They are clean without a trace of sterility and are warm where they need to be. They are limited to .5W, which in crossover may mean a costly bridge of multiple resistors with degrading solder joints. Texas Components manufactures a bridge version with up to three elements in series. Maximum value per element is 100K. |
For someone who has not played with resistors what are the differences and what kind of magnitude? |
A low-TCR resistor like TX2575 sounds detailed, clear & quiet in the manner of a good coupling cap. However it is tricky to compare the effect of a resistor swap to a cap swap, as there are more resistors in path(at least in electronics) and the effect of changes are cumulative. If the electronics are good enough you can hear the sound of a single resistor, particularly around input of phono or coming off DAC and I/V sections. The technology to manufacture a low-noise resistor like TX2575 was simply unavailable in vintage era. |
Years ago I had built up ladder type resistor bridges made from the then state of the art Vishay resistors to replace the cheap low quality sand cast resistors in my SC4's. When I told John Dunlavy of what I was about to do he said it would make no difference and I was about to waste $600.00 in greenbacks. I moved forward with the project and the difference was staggering. Much lower noise floor, details I never heard before in the backround.. speed and clariy everywhere. I would love to compare a new resistor bridge made of TX2575's and a new Duelund. The bridge buildup would certainly cost more. Wow something more expensive than a Duelund component! Tom |
Theaudiotweak,
You've just prompted a price increase... ;) |
As a former commissioned salesman I request a % of that increase on every Duelund component sold hereafter. Thank you for your keen observation and your gratuitous response. I will forward you my direct deposit information. Tom |
|
I will be having some more time in the next month for some more tests.
I have been digging into the recording process more as it seem there was a huge improvement in the late 40's early 50's. It seems the Neumann U47 mic is credited with much of this. The U47 shares much in common with the "Hitler mic". The early U47 used the same capsule as the Hitler Mic. The so called "Hitler Mic" was a blank cheque government design given to Neumann so they could make a mic so good it would capture emotion not just sound.
http://www.wunderaudio.com/CM7sound.html
I understand the early U47 capsules were very complex (and costly) to make.
Duelund have you ever thought about redoing one of these U47's vintage mics with your Silver wire and Silver CAST caps???
We might actually end up with something better than the world has ever seen/heard!
Going back to more regular comparisons here soon and want to start using some Silver in the amps. |
I have done more extensive listening to the Jensen Paper vs. Duelund VSF. often on Mono CD's just to be sure.
The differences
With Duelund sounds are indentified much easier less random sounds. (this makes music more enjoyable)
Duelund has much more natural reverb and tone of each instrument.
Duelund has less midrange drone. What causes mid range drone???
Jensen sounds more mechanical.
Duelund sounds much more rich liquid and complex.
I will in fact not likely be doing any more comparisions except within the Duelund range. (I will leave that to you guys) The thread is starting to sound like an advertisment for Duelund. I can easily hear the difference. I wonder if it is caused by the silk???
It is the same to me since I first put my first Duelund cap in the crossover. Liquid sound. I could not believe it then as I hated my dry CD player before that tweeter cap. It is the same today each time I put in one more of those caps (or wires) the system is more natural with better tone and less random noise.
I do not want to be critical of Jensen Copper Paper tube caps as I think them very good capacitors as I have said before. Duelund VSF is just that much better. |
Took my old Linn Karik CD player to the friend who bought the Khorns after hearing my system.
It has been a long time and many Duelund parts and my speakers sound nothing like original.
What I wanted to know was how does an old $4 (I think) Cd player compare to a new $1k player.
He has one of those new OPPO SE Blu-ray players. First time I have heard one.
It did not sound good to me on CD (forward) but when given a Blu-ray???? Hmmmm? I have asked him to bring it over to hear on my system for better reference.
Anyone heard these Blu-ray players? Clearly the format is promising. |
After being not really impressed with the Bealtes Mono CD box set, I just bought Jimi Hendrix on vinyl that just came out (2010) and it seems not bad to me on first listen.
A little harshness in the upper freq.
I would like to know what equipment they used?
Duelund you really need to upgrades to vintage equipment. A vintage tube mixing board with your caps would be awesome. These caps need to be in professional gear. |
Well,
I'm not telling owners of vintage or professional equipment not to use us... ;)
F |
JohnK posted a long time ago that he felt capacitors were not the most important and transducers were.
John makes a good point as it is the transducer that actually makes the sound so of course this part is going to matter! I was only pointing out how big the sound difference is with Duelund caps.
I was out listening to the friend who has Khorns. I have been a little hesitant to post as he may see this and I did not want to upset him. He has different (cheaper) driver not the Alnico (Western Electric based) ones in the older Klipsch.
His speakers do not even sound anywhere near the same. Is it the Duelund caps, inductors and Silver wire? How much is the transducer and ferrite magnet? I can not say?
We used my CD player and he had the same amp less Duelund and Jensen caps.
I have not been doing much tests lately as I have been replacing vinyl. I bought Jimi Hendrix albums just released. |
Power Supply
I am looking into the Jensen 4 pole. |
Power Supply
I had my tech guy do a partial power supply rebuild on one of my EL84 amps using ASC poly caps in the power supply. He rolled his eyes at me even worrying about the "sound" of something not in the signal path.
The amp had a hum after that and he could not hear on his test speakers.
I only used it for a few hours or so. I thought he had changed some of the coupling caps to poly as the amp sounded very different than every one of the vintage amps I have. I took off the bottom plate to find out he did not change any coupling caps.
The amp had more bass than the old vintage electro caps but sounded slower and had change in tone. I did not like it.
Can power supply caps affect sound? Not just smothness and power but tone? |
Volleyguy,
If you draw a block diagram of the amplifier, it turns out that the power supply is located in the signal path in series with the other elements. This means that every detail of the power supply is located in the signal path and has a significant influence on the sound. |
Micr0
This is very interesting.
I was under the assumption power supply of course affects the amount of reserves and how quickly and quiet the sound. I did not even think it could affect the tone? Part of the reason I did not want to even post it. I just shelved the amp.
I remember reading that Leak used a paper in oil power supply in the Leak Stereo 20 (never heard one) and also hearing great things about the Leak's natural tone.
I did not want to say it but poly in the power supply sounded the same to me as it did in the speaker crossover.
Leak (Quad II's as well Paper in Oil power supply)
http://www.bassboy.com.au/getreel/site/classicamps/files/amps/leak/tl12/amp.htm
http://www.hi-fiworld.co.uk/hfw/oldeworldehtml/quad2.html
I have 2 EL84's same brand. I am going to have to compare Jensen power supply vs. ASC. |
Power supply
I bought several vintage tube amps (all same brand) for tests.
I started all mods on the worst sounding of them which was my Fisher 500c. The reason for this if I messed something up it was the worst sounding amp anyway.
Now after listening to the EL84 (all vintage) the 500c hammers it with all Jensen (copper paper tube) and Duelund VSF caps. So my worst, now my best. (by far)
How did they compare to new? I had new SS (pre and amp 10k here) and ALL of the vintage amps sounded better. (wayyyyy quieter) My worst amp (the most $$$) has been long sold. To my ears it was the best SS I could find in my budget.
What about a new tube amp?
Not a bad idea at all, but I would like Duelund caps all through out. (they are clearly audible over even Jensen) A top notch power supply, Jensen, Black Gate etc. Silver Duelund solid core wire would be nice as well. Problem an amp like this is far from cheap!
Hmmmmm No cheap answers. |
Took apart a vintage Electrolytic.
Just an aluminum foil wrapped in paper. Almost looks like one could make it themselves. Nothing really to it. |
SS vs. Tube rectifier.
Looking for info on this. To me there is for sure something natural about the sound tube rectifier.
Even the (SS based power supply) amp with all the Duelund and Jensen caps sounds somewhat mechanical (although quieter) compared to all vintage cap EL84.
It did before the caps went in as well so no fault of Duelund or Jensen. (the SS rectified sounds wayyy better than it did but still mechanical)
SS rectified sounds more mechanical to me. (maybe Black Gates in the power supply solve this problem?) Tube rectified has different timing.
The question is why??
Diodes?
Big Electrolytic power supply??
Of all the amps from the same company the simplest one with the fewest electrolytic in the power supply sounds best. |
Bought Morgan Jones book Valve Amplifiers.
I need a better understanding of what is going on in the power supply. |
Morgan Jones quote
"If the power supply is poor, then the most beautifully designed amplifier will be junk".
I guess we know how he feels about power supplies. He was complaining how some commercial companies treat the power supply as an afterthought. |
I have been checking around for a WKZ Black Gate to compare against a VK series that is all that is left at Partsconnexion with the phase out.
I contact Audio Note by chance to see if they would sell one and Peter e-mailed back.
Peter said (and I asked him if I could quote him)
"Hate to say this but it is a waste of a good Black Gate to put it in with a solid state rectifier"!
I thought it was too funny.
Maybe I was wasting my time (and $$$) trying to get an SS rectified amp to sound as good as an EL84. One can clearly hear that a tube rectified is more musical to me.
We know where Peter stands. |
Jensen Electroltyic caps in. I have a Black Gate to use as comparison.
(starting to put in tomorrow)
I was talking to Peter Qvortrup about power supply caps. His take Polyester sounds fine 250-450v and polypropylene does not. (can not argue with that) In higher voltage 1kv both fine but polyester better.
He did mention that the diodes are very noisy and have a jagged wave form. So not clean power supply. (but suspects this only part of the problem)
I do not mean to say the Duelund/Jensen capped amp does not sound excellent, it does! It is the timing is different/natural in the tube rectified amp. I fully expect the tube rectified EL 84 to sound of course excellent with the Duelund caps. |
Morgan Jones on Capacitors
"This can be further generalized that high quality capacitors tend to be physically large for their value of capacitance".
I remember noting this a long time ago comparing Sonicap vs. Mundorf Supreme that the Supreme had much more dynamics, of course be much larger in size.
This same effect was also noted comparing Duelund VSF vs. CAST.
I will be comparing in direct comparison Ampohm Copper Foil in Mylar vs. vintage Vishay Foil in Mylar. (likely Aluminum) I had noted that they sounded extremely alike by memory. If the new (and much larger) Ampohm is better and logic says it should be being new and copper and bigger. I am going to replace all of the smaller value caps with Ampohm. I would love to use Duelund everywhere but everyone knows why not. $$$ |
Doing the Ampohm vs. vintage comparision now.
Ampohm is almost exactly 2x as large in volume. So in theory should have more dynamics.
Initial first minutes is like I thought close to vintage. I commented before I did not know if I could tell the difference. It is not like Jensen or Duelund.
The Jensen Electrolytic (not yet in) concerns me vs. vintage as the vintage is at least 10x the volume in size. Will the small one sound better? The Black Gate is much larger than Jensen but not as big a vintage. |
Ampohm Copper Foil vs. Vintage
I thought they sounded very similiar till hearing them in direct comparion at the same time. The Vishay ERO FOL II sounds better. The Ampohm has a distinct tilt in to the upper mid range in sound. I do not care for it at all. Might work for you if you wanted that effect?
On to compare Jensen Electrolytic vs. vintage. |
Of interesting note.
On this EL84 there was a power surge as soon as turned on. When the Jensen electrolytic cap went in. No longer. This makes me feel better at least. |
Didn't fix voltage surge but seems to sound better. |
Changed my first power supply cap.
Not the improvement hoped for. So far it sounds bright to me. I am hoping for break in improvement. |
I am going to start clocking in the hours for break in on the Jensen Electrolytic in power supply.
I have some ASC poly caps here to compare in the same amp in the power supply. This will take some time for the Jensen electrolytic caps to break in. Then for the ASC's as well. (some modifications to make work) I even have a Mundorf Silver in Oil still around that could be put in as bypass. From Tempo's site the ASC is ranked higher anyway?
Right out of the box aggressive and have a bright glare on the Jensen. (I hope for big improvement with break in)
I took out the amp yesterday as I wanted to listen to some music and the Duelund/Jensen coupling cap'ed amp stares at me.
Once again it is not as easy as one would think (or at least me) to replace old parts and get some big improvement (at least out of the box) as long as the old parts were working correctly. |
You certainly don't do things quick and easy. :)
Some day, you might end up doing more cap rolling, than we've done. |
Of course you can always convert the amp to a parafeed-type configuation with a CCS or choke on the plate instead of a resistor and eliminate the PS caps from the signal path completely. That's what I did with my preamp and the results were astonishing. Horizontal load lines are a wonderful thing.
Might be more mods than you are willing to do, however. |
