Archive through May 19, 2006

Gold Member

Username: Nuck

Post Number: 2411
Registered: Dec-04

Posted on Sunday, May 07, 2006 - 09:32 pm:

Bill, the amp went on a hail-Mary to Art's dealer before he got it, you should be confident in the packing and the Great Pumpkin to see a safe arrival.
As well, the package will be stickered with a violence-evident device.If it is tripped, simply refuse the shipment.

Nuck.

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3229
Registered: Feb-05

Posted on Sunday, May 07, 2006 - 09:33 pm:

I don't know Nuck. I never claimed to be a scientist but I know better sound when I hear it.

I blind tested Sherilyn with the Signal Digital Reference vs the Cardas Twin link with my cd player and she was able to consistently tell me which one was in and and always preferred the Cardas.

I tried all different combinations. With the Cardas on the cd player and the Kimber on the PL2 the sound left both Sherilyn and I with our mouths open. Sherilyn kept asking, has that always been on that cd, and I kept saying I think so?. It was a fun and painful (Signal Cable left my ears bleeding - not good synergy with my system) little experiment with a happy ending. The Signal Cables go back to New York and I'm a big believer in the power.........

Bill Collins

Bronze Member

Username: Bcollins

Rockport, MA
United States

Post Number: 99
Registered: Nov-05

Posted on Sunday, May 07, 2006 - 09:54 pm:

Thanks Nuck,

My last UPS package arrived with workboot footprints all over it indicating that someone was actually standing on top of it before it's arrival. No way to avoid it I guess. Just want to get as much info as possible to make a good choice before taking the plunge. Sounds like it might be worth the risk though. Thanks,
-Bill

Gold Member

Username: Nuck

Post Number: 2412
Registered: Dec-04

Posted on Sunday, May 07, 2006 - 10:08 pm:

I can't argue long distance with two good sets of ears, Art.
The science and physics, I could, if there were a point, but there ain't.(cause ears win in our hobby).
I take all under advisement, and send along a toast from Memphis.

Gold Member

Username: Nuck

Post Number: 2413
Registered: Dec-04

Posted on Sunday, May 07, 2006 - 10:15 pm:

Bill, your goods will be delivered as good as new, with abuse-evident packaging, no doubt.
Do you think the shipper would send such a lovely piece of work via tasmanian devil?

No way, man.

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3230
Registered: Feb-05

Posted on Sunday, May 07, 2006 - 10:17 pm:

Cheers Mr Nuck, hope you're havin' a ball in Memphis!

Gold Member

Username: Nuck

Post Number: 2414
Registered: Dec-04

Posted on Sunday, May 07, 2006 - 10:19 pm:

Further, Bill, I am also considering the PL2, however assessing all others in Canadian$, and watching the$ closely.
The Canuck buck may match and exceed the Greenback in the next year, which will open a plethoria of options.

Stay tuned, a few other Northerners will watch closely as well.

Dave&Tim?

John A.

Gold Member

Username: John_a

London
U.K.

Post Number: 4166
Registered: Dec-03

Posted on Sunday, May 07, 2006 - 10:49 pm:

Art;-

Thanks for the recommendation of a better power cord. My dealer gave me a replacement for the one in the box, since it had a continental European plug (quite different). I am inclined to agree with Nuck on this, and he puts it well. You're an honest man and you generously share your experience, leaving me with the problem of how to account for what you describe. Wish we could compare what we hear directly.

Also, with all thanks and due respect, I cannot think how a power cord needs to break in.

Still, we live and learn. I have changed my mind on several issues as a result of reading and discussing, here. The whole idea of tubes seemed crazy to me until I followed Rick, Jan, and the other migrants from Old Dogs, onto this thread. I still have to try polishing CDs, too.

I bought one fabulous-sounding CD today. Will try to find the right thread.

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3231
Registered: Feb-05

Posted on Sunday, May 07, 2006 - 11:14 pm:

Well fella's it's my bedtime as I've reached another work week. I understand your skepticism as I was once a power cord skeptic. All of that was out the window this evening as the goosebumps rose on my arms as my system once again reached a new benchmark for performance and the music I love so much sounded better than ever. Goodnight all.

Silver Member

Username: Paulfolbrecht

Post Number: 186
Registered: Dec-05

Posted on Monday, May 08, 2006 - 02:46 pm:

Hi Bill,

Apologies for being late to the party, but I'll address as best I can your Cayin vs. PL vs. "Carey" (did you mean "Cary"?) question.

Cayin & PL gear have a lot in common. Build-quality is absolutely top-rate on both, from the heavy chasis, ptp wiring, glossy, multi-coat paint, and the many components they have in common (Alps, Nicosen, WBT, etc.). They are also in right around the same league in sound quality and value, which is to say, the highest. Both brands, in my experience, are dead dead quiet as well, as others have pointed out. Each particular amp, due to its design and tube complement, has a unique sound, to some degree. My PL 3 does impart just a bit of thickness to the music, compared to something very open/fast, but OTOH the mids are the most lush and velvety I have heard. This is the most important quality to me. Switching out the PL 3 for anything else has resulted in a diminishing of this aspect, but again whether that's good or bad is really opinion.

I've not had a chance to hear the PL integrateds - after experiencing the quality of the Cayin int I'm a bit sorry I didn't consider them more instead of the separates I bought.

I am running the PL 3 pre with Cary (AES) Six Pacs, which is a wonderful combo indeed. I sold the PL 7 monoblocks I had previously only due to an insatiable desire to play, and a small preference to the Pacs sound, due to whatever reason (0 neg feedback, triode operation, ?). However, the Pacs are not dead quiet as the PL or Cayin gear - there is a bit of hum which I'm able to live with. The fit and finish quality are also much inferior (who cares).

You really can't go wrong with Caying or PL. If you were inquiring about Cary/AES, I also believe it to be 1st-rate stuff. Cary proper is unmatchable for quality but not in the same price/performance bracket - you are paying for American manufacture and much finer finish (than AES, *not* Cayin/PL). AES is also very good value, and sounds the same as anything stamped "Cary" to me anyway. (Don't mean to steer you away from Cary - there are lots of good bargains on audiogon if you aren't afraid of used.)

Once again, I think it very likely you would be quite pleased with any PL or Cayin integrated. Listen if you can, and you're lucky if you can.

Paul

Bill Collins

Bronze Member

Username: Bcollins

Rockport, MA
United States

Post Number: 100
Registered: Nov-05

Posted on Monday, May 08, 2006 - 04:48 pm:

Paul,

Thank you for your feedback. Yes, I did mean "Cary" SLI 80. If sound quality is not significantly different, then I think the Cayin or PL2 will suffice. Unfortunately, I can't auditon either of them. Do you need to open up the Cayin to bias? Does it have a pre-out? Also, how would you describe the difference in sound between the Cayin and PL? Sorry for all of the questions. Thanks,
-Bill

Gold Member

Username: Nuck

Post Number: 2420
Registered: Dec-04

Posted on Monday, May 08, 2006 - 05:09 pm:

And Paul, do you like/trust the auto bias of the PL? (PL2 in this case).

Art as well, how do you feel about the auto bias?

Also is this feature defeatable?

Silver Member

Username: Paulfolbrecht

Post Number: 187
Registered: Dec-05

Posted on Monday, May 08, 2006 - 05:22 pm:

Jan, is this good:

http://www.amazon.com/gp/product/B00025DYJW/qid=1147101201/sr=8-1/ref=pd_bbs_1/1 03-7501698-7014255?%5Fencoding=UTF8&v=glance&n=284507

Gold Member

Username: Nuck

Post Number: 2421
Registered: Dec-04

Posted on Monday, May 08, 2006 - 05:25 pm:

Paul, saving 4cents is always good.
Better than my 2cents.(twice).

Silver Member

Username: Paulfolbrecht

Post Number: 188
Registered: Dec-05

Posted on Monday, May 08, 2006 - 05:26 pm:

I think the auto-bias is slick and wish the Cayin had it. It doesn't, and it isn't manually biased either - bias is fixed (I think that's NOT the right term) - meaning you never touch it. (This is nothing like the PL system, of course, which constantly keeps the bias optimal as the amp runs.)

I know there's no way to turn off the PL autobias but there's no reason you'd ever want to either.

Gold Member

Username: Nuck

Post Number: 2422
Registered: Dec-04

Posted on Monday, May 08, 2006 - 05:34 pm:

This PL2 is looking better and better.

I would dearly love to hear it, to see if it fits my music tase and style.

I didn't find a dealer in Toronto, perhaps a better search or a call is in order.

Thanks.

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3234
Registered: Feb-05

Posted on Monday, May 08, 2006 - 09:18 pm:

For me the auto bias is a blessing. No fuss just listen. Perhaps there will come a day when I would want the manual bias but I can't imagine why.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8407
Registered: May-04

Posted on Tuesday, May 09, 2006 - 01:31 pm:

No hifi talk here, guys.

PF - Yep! Bialetti is the originator of the modern stove top espresso pot. The price is good on this model though there are other brands which have duplicated the Bialettit technique and sell for either more or less depending on the physical style of the pot. I have the La Signora 6 cup, the Bialetti 9 cup "Brika" mocha pot which includes a pressurized stem for more crema, a Bialetti one cup pot and an unknown manufacturer's pot which replaces the upper metal pot with a ceramic pitcher. I also have a French press though I've never much cared for the coffee it produces. I use the La Signora everyday simply because I like the look and feel of the pot. I bought it at World Market, if you have one in your neighborhood, for about the same price as the Bialetti. I've also sent a nephew a pot similar to the Bialetti that I bought at the Mexican food store here in Dallas for $9.99. The stove top pots make espresso taste differently than a counter top espresso maker, they are easier to clean and are the preferred method for the home in Italy.

Of course, the results you get depend on the coffee you use. I buy a double French roast that I get at a local market. It's a very dark roast, so it has a bit less caffiene than many other roasts, and has an very oily look in the canister. The taste is rich and finishes with a slightly bitter end. It doesn't keep well due to the oil content being released in the roasting process, so I buy it a pound at a time to last a week or so. For the stove top pots don't grind your coffee quite as finely as you would for an espresso maker or you'll end up with more grounds in your cup. I also replaced the gasket on my pot when it wore out with a higher temperature rubber that a gasket company in town cut for me. It makes a better seal for less pressure leaks when the pot is on the stove. There's no need to replace the gasket on a new pot but just something to keep in mind when the time comes.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8408
Registered: May-04

Posted on Tuesday, May 09, 2006 - 01:45 pm:

Auto bias and fixed bias are basically the same creature. PL has adopted the McIntosh version of fixed bias and, with a slight twist, renamed it auto bias. They both serve the same function and adjust the bias by way of a circuit centered around the plate current draw which increases voltage slightly as the tubes age. There are, as usual, advantages and disadvantages to the fixed/auto bias scheme. Adjutable bias allows the user to trim the tubes to produce a "hotter" or "cooler" running amplifier and therefore sound quality. Remember, bias, in this case, adjusts where the tubes turn on and off during the push-pull cycle. So, adjustable bias allows the user to trim the amplifier more to the class A side of operation, with its attendant sound, heat and shortened tube life; or to trim to a cooler running amp with the same qualites in consideration. None of this can be done with fixed/auto bias without changing out resistors inside the amp. Non-adjustable bias does mean you do not require matched output tubes when you replace tubes, though the cost difference still makes it wise. However, even more so than with an adjustable amplifier, you must stay within the voltage range of any output tube you put in the amp. Placing a tube which prefers to run hotter in a fixed bias amp will degrade sound. Using a tube which can't tolerate the higher plate voltages of most fixed bias amps will result in premature, if not immediate, tube failure.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8409
Registered: May-04

Posted on Tuesday, May 09, 2006 - 01:49 pm:

Also, the McIntosh, and therefore the PL, version of fixed bias is slightly different in where it is taken on the transformer tap than most fixed bias schemes and has some advantages most fixed bias amps don't possess. Though fixed bias is a good scheme of operation in a Unity Coupled amplifier, adjustable bias would be, in my opinion, more desireable in an UltraLinear amplifier.

Gold Member

Username: Nuck

Post Number: 2433
Registered: Dec-04

Posted on Tuesday, May 09, 2006 - 03:54 pm:

Where would the SQ88 by SoundQuest fit in the mix here?
55wx2, auto bias, kt88's, with easy roll in via the auto bias?
The use of kt88's seem like a natural for my musical tastes(?) and usage.
It looks nice and I believe it can be had for 1k as opposed to the 1.5k list.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8413
Registered: May-04

Posted on Tuesday, May 09, 2006 - 06:46 pm:

How about a web site. What do you mean by "fit in"? What makes it "look nice"?

Gold Member

Username: Nuck

Post Number: 2446
Registered: Dec-04

Posted on Tuesday, May 09, 2006 - 08:35 pm:

http://www.questforsound.com/amps/amps_sq88.htm

Sorry, Jan.

There is a link to a stereophile review that doesn't say much more than the spec sheet.

Gold Member

Username: Nuck

Post Number: 2447
Registered: Dec-04

Posted on Tuesday, May 09, 2006 - 08:42 pm:

http://www.questforsound.com/amps/amps_sq88.htm

Sorry, Jan.

There is a link to a stereophile review that doesn't say much more than the spec sheet.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8415
Registered: May-04

Posted on Wednesday, May 10, 2006 - 12:25 am:

Sorry, Nuck, the information doesn't say much. Whoever wrote the review seems to have never been around a tube amp before let alone listen through one. It might be a very good amplifier, but nothing I see indicates anything one way or the other. If you can listen before you buy, then it's worth the effort though the review continually points to the B&K amplifier sounding better in many areas. Possibly that is just the bias of someone who appears to be rather unfamiliar with tubes.

Gold Member

Username: Nuck

Post Number: 2454
Registered: Dec-04

Posted on Wednesday, May 10, 2006 - 04:51 am:

Yeah, sure reads that way.
I'll scratch around a bit.

Silver Member

Username: Paulfolbrecht

Post Number: 190
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 12:18 pm:

Jan - bout the espresso maker - I was nearly certain that was the type you had referred to somewhere back in the archives, but wanted to make sure. I coworker bought one recently and raves about it.

I have yet to visit Italy, but will be in Rome in a couple days. Vacation. Well, more of a Catholic pilgramage actually, with my mom and girlfriend (no, really). I do hope to enjoy some fine espresso there. (I wish there was more 'personal' time, as I've always completely loved Italian culture, everything about it, and just want to soak it up.)

Talk to you gents in a couple weeks, probably.

(Nuck, I'd love to see you with some toobs by the time I get back. :-})

Gold Member

Username: Nuck

Post Number: 2473
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 12:19 pm:

Another topic entirely...

Input sensitivity.
Aforementioned tube amp is rated input 290mv.
To achieve max performance, I might want to use 270-275 output from a cdp for the amp.
What would be the best way to modulate this(assuming the input had 320 or more capacity)?

These numbers all seem kind of high, Perhaps 250 input and 300 max out from the cdp.
cdp does not have volume control.

As well, how would tubes in general respond to over input voltage as compared to a decent ss amp given the overinput?

These specs are not always given.

Cheers!

Silver Member

Username: Paulfolbrecht

Post Number: 191
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 01:02 pm:

Nuck,

If want an excellent passive, single-input line stage (volume control), do an eBay search on Axiom. About $150.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8426
Registered: May-04

Posted on Thursday, May 11, 2006 - 02:04 pm:

I assume when you say 275-320 you mean millivolts. The "250 input and 300 max out" means 250mV sensitivity. And, by "modulate" you mean change the overall volume and not modulate the voltage.

First, you have to consider the output voltage quoted is maximum (the output voltage at any one moment is modulated by the signal) and full output voltage will not be reached in most situations. Second you should consider that 250mV sensitivity is fairly high and will have your volume control operating in its most non-linear range. Channel tracking can be a problem with most potentiometers in the lowest portion of their range.

If you choose to go with a passive control device, you have to understand the limitations of passive units. There are typically no buffering circuits in a truly passive "pre amp" unless you use a transformer based unit. With no buffering, you initially have to assure yourself and your amplifier the CDP doesn't pass any DC voltage. Depending on the input filtering in the amplifier, a little bit of DC passed from the player to the amp can cause large DC offsets at the amplifier outputs. With an output transformer coupled amplifier, the problem is not what will happen to the speakers but rather what will happen in the amplifier itself.

With no buffering to maintain a constant output impedance from the player, this value becomes dependent upon the relative position of the volume control and the cabling used. Most listeners find the lack of active circuitry appealing for its clarity but stall when they find the dynamics and frequency extension of the system can only be found at one, usually loud, listening level. Passive systems also limit your system set up to short (1 meter) cables with very low capacitance and inductance.

The trend in passives has been to transformer coupled systems. The quality of the transformer then dictates the quality of sound and the best transformers aren't cheap. You can always try wiring up an Alps pot to your line out from the CDP and then determine if it will suit your system and tastes. That's the cheapest way to go, but not always the best approach.

Silver Member

Username: Paulfolbrecht

Post Number: 192
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 02:24 pm:

Interesting, Jan. I was aware of all the limits and issues of passive linestages except the DC thing.

I bought the Axiom unit as an experiment and it sounds great in my system, but I have indeed noticed I need moderately loud levels to get good sound.

Do you have an op on autoformer-based linestages, such as the Sonic Euphoria unit?

www.soniceuphoria.com

Gold Member

Username: Nuck

Post Number: 2481
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 02:54 pm:

I was asking because the spec sheet on the sq88 amp above was calling input at 290mv.
Seems kinda high for some reason.

Gold Member

Username: Nuck

Post Number: 2482
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 02:55 pm:

Covering up a Q with the pre-tubes?

Silver Member

Username: Paulfolbrecht

Post Number: 193
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 03:02 pm:

Nuck, an input sensitivity of 290mV is extremely *low* (which is good). This is the voltage the amp needs to develop full power. Most CDPs put out about 2V, as I'm sure you're aware.

Gold Member

Username: Nuck

Post Number: 2483
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 03:24 pm:

Sure Paul, this where I have the Q.
If I over input to the amp, how will this affect a tube vs. a ss amp?
Neither is desirable, but how are inputs isolated in the tubes as compared to (idiot light) ss?

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3246
Registered: Feb-05

Posted on Thursday, May 11, 2006 - 03:42 pm:

Well folks my experiments with tube dampers are over. They appear to alter the sound to a far greater degree than I thought they would. The changes are a mixed blessing and that is the problem. There never appears to be an improvement that isn't accompanied by a negative change which leads to an even bigger problem.....imbalance.

Silver Member

Username: Paulfolbrecht

Post Number: 194
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 04:24 pm:

Nuck,

Sorry - I misunderstood the gist of your inquiry. As for overdriving... just don't turn up the volume all the way. Virtually any tube amp has an input sensitivity well below 2V so feeding it a source or preamp signal at full strength is not likely to be a good idea - but why would you do that?

Gold Member

Username: Nuck

Post Number: 2484
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 04:42 pm:

Paul, it's in my nature.
The amp in question is http://www.questforsound.com/amps/amps_sq88.htm

and I questioned the input range, leading to my Q.

Gold Member

Username: Jan_b_vigne

Dallas, TX

Post Number: 8427
Registered: May-04

Posted on Thursday, May 11, 2006 - 07:20 pm:

"Do you have an op on autoformer-based linestages, such as the Sonic Euphoria unit?"

No, never heard it and I don't know anything about it other than what we can both read.

Semantics are misleading here. The 290mV sensitivity is a high sensitivity which means the amp will be driven to full power by a low level of voltage at the inputs.

But 290mV is extremely low. I have no idea why the sensitivity would be so high. Tubes will be a bit more forgiving than soild state here, but this is a level that would seem to be asking for the inputs to be overdriven.

Gold Member

Username: Nuck

Post Number: 2488
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 09:33 pm:

And I be not-understaning the last post, Jan.
The higher output, which could be biased, into fixed-max input to an amp might work?
I am trying not to press any part past 90%nomminal, unless thats where the fun is.

Silver Member

Username: Paulfolbrecht

Post Number: 195
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 10:56 pm:

Art - surprised about the tube dampers. Never have read of them causing *problems*. Kinda hard to imagine how dampening vibration-induced microphonics could ever be *detrimental*. Not doubting you. Can you elaborate on what you heard?

Gold Member

Username: Nuck

Post Number: 2499
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 11:15 pm:

Art, did the 'chastity rings'slow things down?

Silver Member

Username: Paulfolbrecht

Post Number: 196
Registered: Dec-05

Posted on Thursday, May 11, 2006 - 11:18 pm:

lol

Gold Member

Username: Artk

Albany, Oregon
USA

Post Number: 3249
Registered: Feb-05

Posted on Thursday, May 11, 2006 - 11:35 pm:

http://www.magnan.com/pages/tweaks/tubedampers.html

I tried the last 2 dampers mentioned and still experienced some of the negative effects mentioned above. The description of the problems with the 3M's is very accurate. The bass appeared to be exaggerated, midrange lost much of the warmth I had experienced and enjoyed, and the high end was bright. On the positive side the soundstage was huge which only tended to exaggerate all of the other problems.

The FEP teflon coated silicone o-rings didn't fit as tight and were easier to apply. The sound was better as well. The best way I can describe what I heard was that the instruments sounded out of proportion to each other. The sound with both dampers was more focused and clear but instruments lost some of their naturalness and sounded a bit plastic. It's difficult to describe.

Changing out the stock power cord is the most beneficial thing I know of to improve the amp.

Gold Member

Username: Nuck

Post Number: 2504
Registered: Dec-04

Posted on Thursday, May 11, 2006 - 11:43 pm:

Difficult to describe sounds like the hobby/affliction we all share.

Just a little bit of...

John A.

Gold Member

Username: John_a

London
U.K.

Post Number: 4171
Registered: Dec-03

Posted on Friday, May 12, 2006 - 05:30 am:

June HiFi News has an article on tube/valve dampers/coolers and,after a lot of measurements, reaches much the same conclusion as you, Art.

The microphony comes in by vibrating the filament inside, so adding mass to the glass wall can affect that, but it is difficult to predict how.

Gold Member

Username: Nuck

Post Number: 2509
Registered: Dec-04

Posted on Friday, May 12, 2006 - 08:34 am:

Are pre/inputs more or less affected by the microphony?
Or is the damping most effective on the oputputs?