Serious Modifications

[4krow]

Randy,

   I KNEW that was sycamore! It is one of my alltime favorite grains. The grain seems to interlock.
  Now, I get the idea that you want to customize an amp, but my question is, since you will be building speakers that are 97db sensitive, why would you need more than a couple of watts?
  This has become a fascinating thread by the way.

[drewh1]

Hey Greg,

You might have Randy and I confused - I was going to build some FR Metronomes but am holding off now. Everything sounds too damn good. The GMA's are sounding great and loud enough. Randy is using Orca's and is super pleased with them.

I just want to build more stuff, and I can afford it  if can just sell this other stuff . . .

drew.

[rlyach]

Yes... I wanted to build some speakers but I was having trouble finding a full range driver and I am afraid of veneer. I was trying to design my own integrated stereo 300B system (using a parafeed topology) but I realized I don't know enough yet. I also don't have the funds to experiment with different components. So I ended up purchasing a 300B kit which uses a direct drive topology and a two stage pre-amp circuit. I also ordered a pair of Omega Super 3Ss to go with it. The Omega's are 94 or 94.5 db efficient so they should be a good match for the 300B's. By the way, the Orcas with the Stereomour keep getting better. The more the system breaks in the better the response. The bass response is around 75 Hz even though the driver is only rated at 100 Hz. The ported cabinets are very well tuned.

[4krow]

Yah, at least I got part of it right. The Sycamore really looks good for that base. I still have some in my stash. I have had it too long for it to just sit there any longer.

[rlyach]

Drew,

Thanks for the offer of the tube. To tell you the truth, I have not even listened to the kit tubes yet. I plugged them in to do the final voltage checks and then immediately switch to the JJ 40W tubes I purchased. I have only listened to the JJ's. They also have a larger bottle than the standard 2A3. I think it is the same size as the 300B bottle. I think they sound very good and now that they are getting broken in, I don't want to switch them out. I will keep the Sovteks for a future use.

[drewh1]

FYI - it is a driver tube  - I am playing around with driver tubes because it is fairly inexpensive! Can't afford those big guys and still really thinking about the next build.

[rlyach]

Sorry, I was confused on terminology. I assumed driver tubes and power tubes were synonyms. My bad  . I always called this the pre-amp tube or the gain stage. I guess I have never heard it called a driver tube before. Anyway, in reference to the driver tube I am in the same boat. I am using a JJ gold pin 12AT7 and have never listened to the kit tube. Maybe I should! I am so satisfied with the current configuration that it never occurred to me to change it.

[drewh1]

 I had a bad 12at7 tube shipped and replaced it with the JJ Goldpin too.  When I got the stock tube last week, I dropped it in just to see if I could hear a difference. I really like the stock tube better than the JJ. I noticed a lot more clarity and separation, better all around.  So I have the JJ sitting in a box now. My experience anyway.

[4krow]

I have to agree about stock tubes. It's not like a so-so product was sent. Probably had an evaluation before it was chosen to begin with. I have been rolling in my Quickie, and the stock tube rates quite high. I was just lucky enough to get a couple of NOS Telefunkins that have the edge over some others that I have tried.

[drewh1]

I am trying a NOS Telefunken next, I would also like to try the Mullard (I hear that is what Doc uses!).  I will have a spare Telefunken if anyone wants to trade for a Mullard (just to try them out).

Those about the only ones I am interested in right now. For me it is just to try some different things to hear them, not really feeling the need to improve necessarily.

[4krow]

FWIW The Sylvanias that I have used in my Quickie were promising, but honestly I don't think that they were broken in yet. They still had a bite to them. So may upgrades you can do, but not many are as easy to hear and do as rollin'

[rlyach]

You guys have got me wondering so.... I just ordered an NOS Mullard CV tube. I will let you know after it has broken in a bit.

[drewh1]

well I am glad to hear that Greg likes the Telefunken as I am not so patiently waiting to get mine. Seems they shipped from Siberia or something.

[Grainger49]

I got capacitors from Canada and tubes from Ukraine this week.  The USSR military surplus electronics sometimes come from Siberia.  It isn't unusual.

[drewh1]

Ha, I was attempting sarcasm! but you have a good point Grainger.