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Nightbrace
02-10-2006, 02:43 PM
I am considering using a Dynaco PAS-3 tube pre-amp along with a McIntosh amp. I only need about 80 watts a channel to run a set of either L65 Jubals or L100T's, I haven't decided which set I am getting. Does it matter which amp I choose depending on which set of speakers I get?

Do you guys like this combo? Not sure what McIntosh amp I will get, but don't want to spend over $500. This being the case, would I have to settle for something else? Or could I just bypass getting the Dynaco completely and use an integrated amp by McIntosh. What kind of results have you guys gotten with the Integrated Hybrids?

I love what tubes do to the preamp stage, and have not bought into the hype of using tubes for an amplifier for a home system. For a guitar tubes are an essential part of the music, but for home listening, they are a pain and ti get them to sound right at high volumes is just not worth it, at least not for me.

Harkness
02-10-2006, 02:53 PM
as much as i love a nice tube pre, if i had to have only one tube section i think i'd make it the power side. my jbl's are much happier connected to an output transformer and they are so effecient that i am quite happy with my 15 watt tube monoblocks. i can shake the walls with a few watts.

i've had several amps hooked up to my jbl's and even my GF noticed that there was a difference with the tube power.

not a big PAS3 fan either. kind of gritty IMO.

my first "fall in love with jbl's" experience was with my garage sale obtained LE8 trimlines driven by my leak tube pre and dyna stereo 35. wow! wish those pieces hadn't got stolen. :(

of course YMMV etc. etc.

Nightbrace
02-10-2006, 02:53 PM
Am also considering a Marantz 15, 16, or 32 amp, I have heard great things about these amps and they cost half what a comparable McIntosh would.


http://cgi.ebay.com/McIntosh-MC2505-POWER-AMP-PERFECT-MUESUEM-QUALITY-MINT_W0QQitemZ5864432122QQcategoryZ71548QQrdZ1QQcm dZViewItem

I doubt the bidding is over on this amp, but will it have enough power?

Mr. Widget
02-10-2006, 06:40 PM
The MC2505 is a very pretty amp and does have quite a following... at the risk of pissing off a fellow forum member, I'd suggest that the MC2505 isn't one of McIntosh's better amps from a sonic standpoint.


Widget

speakerdave
02-10-2006, 10:05 PM
In the $500 range the MC250 or MC2100 may be all the McIntosh solid state stereo power amp you will get. You don't need the meters in the 2505 or 2105.

These are McIntosh's first generation solid state and are reputed to be voiced like their tube amps. As Widget says, they have a following, but my second generation Mac is clearly better, and there have been many after that.

The only advantage of these early Mac transistor amps for what you contemplate is that they have output transformers and therefore high input impedance (250K Ohms), and that means you could use any Dyna tube preamp and don't need to look for the PAS3x. It is also true that these amps have a smooth sound quality that is not fatigueing to listen to.

I do believe that transformers in the output of an amp, tube or solid state, can have an effect on the sound of the woofers which in some cases may be perceived as beneficial, although I do not understand why. Also, they may not be a good match for other woofers. The woofers, the output of the amp and the passive crossover, if used, are all one circuit, and every element added or subtracted will make a difference.

If you want a tube preamp the Dyna PAS is probably the cheapest you will find. It has certainly been the first tube preamp for a lot of other people, so it is a reasonable idea.

I've used the Dyna PAS and the Mac MC250, but never together. The combination would not be the last word in fidelity and definition, but will give you a pleasant sound which you might find quite enjoyable. I've actually had many PAS's over the years (for a time they were almost difficult to avoid at garage sales), and it was always rewarding to hear one playing once again. A lot of the ones I've seen had the original Dynaco tubes, which I believe were Telefunken. Also, the PAS was the subject of numerous modification articles over the years. The chief culprit affecting the sound quality seems to be the power supply, judging from what I've read, and then comes the parts quality. All PAS's are old, and you should not expect blueprint performance as is. If one has been modified it might be very good (and higher in price) or it might be a butcher job.

The MC250 actually served me for many years when I put hi fi on the back burner and devoted fifteen or twenty years to raising my kids. It was very reliable and inoffensive and had adequate power for my very efficient speakers.

David

Nightbrace
02-10-2006, 10:11 PM
Thanks, if I like the Dynaco as a pre, what would be a good upgrade from there?

speakerdave
02-10-2006, 10:16 PM
It is tempting to say, "All the other ones,' but that would be a little supercilious. I would say the best dollar bargain in tube preamps now are the early Conrad Johnson PV series. They sometimes go on ebay for well under $500 dollars. Sonically my PV2 was a very large step up from Dyna PAS. It's a six-tube preamp.

David

Nightbrace
02-10-2006, 10:25 PM
Do you like my idea of using a tube pre and solid state amp?

speakerdave
02-10-2006, 10:30 PM
Do you like my idea of using a tube pre and solid state amp?

It's a combination that can work.

Nightbrace
02-10-2006, 10:32 PM
What about a hybrid integrated MAC? Any experience with these?

speakerdave
02-10-2006, 10:34 PM
What about a hybrid integrated MAC? Any experience with these?
Never tried one.

Mr. Widget
02-10-2006, 10:36 PM
What about a hybrid integrated MAC? Any experience with these?I had an integrated Mac... tube pre SS amp, maybe a 6100??? I don't remember the model. It was absolutely nothing to write home about.

I have liked the Audible Illusions preamps. They have been quite open and spacious sounding. I believe they are no longer all that popular so they may be more affordable.


Widget

speakerdave
02-10-2006, 10:46 PM
You have stereo preouts or just one?

Sometimes you'll find a "center channel" preout on the old equipment.

speakerdave
02-10-2006, 10:52 PM
Well, there's your tube preamp.

Nightbrace
02-10-2006, 10:52 PM
http://cgi.ebay.com/Audible-Illusions-Modulus-3-Pre-Amp-GOLD-MOVING-COIL_W0QQitemZ5863712039QQcategoryZ14974QQssPageNa meZWDVWQQrdZ1QQcmdZViewItem

This unit looks fantastic and it has 4 tubes. Almost in my price range, $75 cheaper and I'd bid.

I agree about the Conrad Johnson pre-amps, just a bit too costly for me, even the earlier ones. They have a strong following and people pay big $$ for them.

Nightbrace
02-10-2006, 11:24 PM
ATTN: Mr. Widget, is this a pre-amp I should keep an eye out for?

Nightbrace
02-11-2006, 12:27 AM
what about these PS audios? http://www.audioclassics.com/cat.php3?cat=Preamplifiers&p=2