An interesting observation.........

Wayner · « **on:** 13 Mar 2009, 11:52 am »

Last Thursday I received my Insight 170 upgrade from the UPS man. For those unfamiliar with the 170, it is built into the old Dynaco Stereo 120 cage. It boasts 85 watts RMS per channel. Well, I had yesterday off from work (as well as today) and had the system on all day. About 4 o'clock, the wife came down with a glass of wine and said lets spin some vinyl. I said, I want to maybe hook up the Ultimate 70 as I have been playing the 170 almost all day. Well, we listened to one side and I made the change over. My wife said, I saw you change the wires and cables over to the other amp, but it sounds almost the same.

I looked at here funny and then listened to the other side of the first album. Damn, she's right. The sonic signature of the 170 and the U70 are almost the same (except the 170 has more muscle and a little more bass). This is absolutely great.

The system is AVA Insight+ EC preamplifier, the 2 amps and my newly remade Dynaco A25XL speakers. Perhaps it's the preamp and the new chips, perhaps it's the Insight 170 upgrade. I don't know. I do know it sure sounds awesome.

Wayner

Art_Chicago · « **Reply #1 on:** 14 Mar 2009, 07:36 pm »

Pretty cool, Wayner! Have you checked these two amps with different loudspeakers? It would be intersting if they sounded similarly with Paradigms and Focals also.

Wayner · « **Reply #2 on:** 14 Mar 2009, 07:44 pm »

I actually have done that, Art. However, the new favorite is my new cabinet Dynaco A25XLs. They are frickin' awesome. Today is tube amp day and I'm listening to the U70 and some Alan Parsons. It's 3D from almost any point in the studio. Tomorrow I'll put the 170 back into play. It sure is fun.

Wayner

orthobiz · « **Reply #3 on:** 14 Mar 2009, 07:55 pm »

Wayner,

I love following your audiophool adventures (guess I need to get a life!).

Paul

Art_Chicago · « **Reply #4 on:** 14 Mar 2009, 08:01 pm »

Quote from: Wayner on 14 Mar 2009, 07:44 pm

Today is tube amp day and I'm listening to the U70 and some Alan Parsons.

Wayner

Man! Tube amp DAY! You certainly know how to spend free time

So, what about Dynaco's that make them better? It is a shame, but I am not familiar with any of speakers you have.

avahifi · « **Reply #5 on:** 14 Mar 2009, 08:33 pm »

I am not at at all certain about what made the Dyna A-25, A-25XL and A-50 loudspeakers "better". However I sold tons of them "back in the days" and they certainly were an outstanding compromise of good range, very low "harshness", good transparency, very low coloration, and just speakers that were easy to live with. They emphasised nothing, traded off nothing for "more but fat bass" extended but harsh highs, and so on like most of their competitors did. They were simply nice speakers, very nice for their vintage. I will demand that Wayne brings his here the next time he visits me.

By the way I had an interesting listening session this afternoon. One of my clients brought in his amplifier, one he had lusted for for a long time. A ton of Macintosh 275 vacuum tube power amp (list price $4000-$5000 or thereabouts I think. We compared it to the latest Ultra Double 550.

The Macintosh was musical, fatigue free, and easy to listen to, but gee, it has been a long time since I have heard so many rubber guitars and wood blocks. I am pretty sure a pair of U70 amps bridged mono would beat it easily too. I really wonder what they were listening to and for at the Mac factory. Transients response, bass definition, and high end extension were just so missing. A big lovely sound field, yes. But so does the Double 550 and without giving up so much of the reality of the music to get it.

I think another Double 550 order will be coming in soon.

Regards,

Frank

Wayner · « **Reply #6 on:** 14 Mar 2009, 08:41 pm »

Yes, I will bring the Dynacos with when I come over. I am also bringing ARMOD turntable for you to audition as I think it's the best table in the house right now.

Wayner

Wayner · « **Reply #7 on:** 14 Mar 2009, 08:47 pm »

Can we bridge 2 U70's together (one per channel)? I think that might be awesome!!!

Wayner aa

avahifi · « **Reply #8 on:** 14 Mar 2009, 09:42 pm »

Hi Wayne,

Yes we could either run the Dyna A-25s on bridged U70 amplifiers, or - - - for even lots more fun, on bridged Ultra Double 550 amplifiers and see how loud they can go.

I need to have Matt build a new Insight Bridge first, probably this coming week.

Best regards,

Frank

Wayner · « **Reply #9 on:** 14 Mar 2009, 10:42 pm »

Thanks Frank, that will be fun.

Art, the Dynaco A25 series of speakers was the largest selling speakers in the history of audio, selling more then 1.6 million units, or 800,000 pairs. They were very inexpensive for the day, selling for under $200 for the pair. They image like crazy and there is no listening fatigue at all. The high frequency cross-over was crazy low, and resulted in amazing acoustics.

Wayner

Listens2tubes · « **Reply #10 on:** 15 Mar 2009, 05:16 pm »

Funny thing after reading your recent posts regarding the A25's I just found these http://newjersey.craigslist.org/ele/1075732536.html

Wayner · « **Reply #11 on:** 15 Mar 2009, 09:20 pm »

Those are A25s, not to be confused with the A25XLs. They have completely different drivers. The A25XL can handle more power and it's 1" dome tweeter has extended range capabilities. However, the A25 and A25XLs share similar voicing and usually if you like the one, you will like the other.

The woofer of the A25 has a much smaller magnet assembly, and the tweeter is 1 1/2" (H087). The A25XL's woofer has a much larger magnet structure and it's 1" tweeter (H086) can also handle more power. These were also the same drivers in the A35, the cabinet volume and double aperiodic chambers being the difference.

A word of caution if you consider a pair of these speakers is needed here. The woofer input coupling did not fair well with the test of time and in many instances, has fallen apart. This is the connection terminal where the flex wire and the hook up wire terminate together. The fix is simple and I have written a paper on how to do it and where to get the parts, but these speakers may not be plug and play. There is no problem with the tweeter or cross-over.

Wayner

rcag_ils · « **Reply #12 on:** 15 Mar 2009, 10:28 pm »

I have a pair of A25XL which have been sitting in the closet for the longest time, they both work, never been taken apart, the reason that I've left them where they are is I thought speakers that old, the caps would have to be replaced and I simply don't have the time. Are they really that good comparing to the newer speakers of today?

martyo · « **Reply #13 on:** 16 Mar 2009, 01:24 pm »

Quote

By the way I had an interesting listening session this afternoon. One of my clients brought in his amplifier, one he had lusted for for a long time. A ton of Macintosh 275 vacuum tube power amp (list price $4000-$5000 or thereabouts I think. We compared it to the latest Ultra Double 550.

The Macintosh was musical, fatigue free, and easy to listen to, but gee, it has been a long time since I have heard so many rubber guitars and wood blocks. I am pretty sure a pair of U70 amps bridged mono would beat it easily too. I really wonder what they were listening to and for at the Mac factory. Transients response, bass definition, and high end extension were just so missing. A big lovely sound field, yes. But so does the Double 550 and without giving up so much of the reality of the music to get it.

Frank, I think the term "they" like to use for describing that type of sound is "refined".

turkey · « **Reply #14 on:** 16 Mar 2009, 03:09 pm »

Quote from: avahifi on 14 Mar 2009, 08:33 pm

I really wonder what they were listening to and for at the Mac factory.

The cha-ching! of the cash register was so loud they couldn't actually hear what the amp sounded like.

Or perhaps they used their speakers with the hundreds of drivers during the design process. Those puppies sound so bad that rubber guitars and wood blocks would be an improvement.

heiba · « **Reply #15 on:** 16 Mar 2009, 07:49 pm »

One can build new similar A-25s:

http://www.t-linespeakers.org/classics/dynaco.html

Using these drivers from Madisound:
Morel MDT30 tweeter and
SEAS Prestige 25F-EW (H0085) 10" Paper Cone (Dynaco A-25 Replacement)

Ola

rcag_ils · « **Reply #16 on:** 16 Mar 2009, 08:00 pm »

Quote

One can build new similar A-25s:

I wish I had a fully equipped woodshop, and didn't have a full time job, wife and kids that share my hobby, with unlimited fund to support my hobby. A big house with plenty of space for my collection.

Wayner · « **Reply #17 on:** 17 Mar 2009, 12:31 am »

That's why I have 2 jobs.

Wayner

turkey · « **Reply #18 on:** 17 Mar 2009, 12:52 pm »

Quote from: Wayner on 17 Mar 2009, 12:31 am

That's why I have 2 jobs.

Wayner

How do you work 2 jobs and still find time to clean all your records?