Preamp Tubes? - Who, What, When, Where, Why, and How? - Page 17

RiverRatt · 06-14-2009, 11:56 AM

That picture looks like it's a 7189 Sylvania. If so, it should be good to go in an EL84 amp.

Scratch that. I just took another look at the picture and it is a 7189A. Bad luck there. Still, take a look at that second link I found before you give up hope.

MartyStrat54 · 06-14-2009, 01:49 PM

Looks like the unit was made around 1962. That's the date code showing on the 7189A. Too bad they weren't 7189's. I looked at the prices and then I looked at what he was asking for EL34's. Holy crap...those are "each" prices and not per pair. I think I did real good on my xf4's for $99. Not to mention they tested NOS.

It's been a while since I've been to that site. It's amazing how many tube brokers are out there and how many tubes are still left, if you've got the cash.

He also made the comment that GE was the only company that made the 7189A. If he really knew his tubes (and tube identification), he would know that good old Sylvania made the tubes for GE. (As I said, by the late 50's and early 60's, it was common for GE to have Sylvania make several dozen types of tubes for them and have them labeled GE. Everybody was wanting to get out of the tube business. That's why there are some damn good Japanese tubes out there. Sylvania kept their tube plants open longer than RCA.)

Marty

Marty

joshuaaewallen · 06-14-2009, 04:02 PM

Quote:

Originally Posted by RiverRatt

Here's another page that has more info on the 7189A - sounds like they could be interchangeable in the right circuit.

7189A Tube Differences

So, if I read that right... The 7189A is a suitable "upgrade" to an EL84, and can handle higher voltage, but... An EL84 may not work that well (or at all) as a replacement for a 7189A?

... I may be reading that wrong. I am waay underslept and amp hopped up on energy drinks right now...

joshuaaewallen · 06-14-2009, 04:14 PM

Quote:

Originally Posted by MartyStrat54

Looks like the unit was made around 1962. That's the date code showing on the 7189A. Too bad they weren't 7189's. I looked at the prices and then I looked at what he was asking for EL34's. Holy crap...those are "each" prices and not per pair. I think I did real good on my xf4's for $99. Not to mention they tested NOS.

Looks like some of these may be worth a couple buck on eBay... If folks are actually buying.

Quote:

Originally Posted by MartyStrat54

It's been a while since I've been to that site. It's amazing how many tube brokers are out there and how many tubes are still left, if you've got the cash.

Think it's wise to just list them and see what I can fetch, or shelve them for a later date when they may be more in-demand? Either way...

Perhaps I can contract w/ you to test some of these tubes for me so that I can have accurate stats on them for selling, trading, or whatever. I'd make it worth your while...

joshuaaewallen · 06-14-2009, 04:17 PM

Quote:

Originally Posted by MartyStrat54

... He also made the comment that GE was the only company that made the 7189A. If he really knew his tubes (and tube identification), he would know that good old Sylvania made the tubes for GE. (As I said, by the late 50's and early 60's, it was common for GE to have Sylvania make several dozen types of tubes for them and have them labeled GE. Everybody was wanting to get out of the tube business. That's why there are some damn good Japanese tubes out there. Sylvania kept their tube plants open longer than RCA.)...

I'd venture to say that the more time that passes since the American tube plants have shut down... Then the more abundant inaccurate information will become... And be taken as "gospel" by ignorant folks like me who don't know any better... Boy am I glad to know you guys!

RiverRatt · 06-14-2009, 04:41 PM

Quote:

Originally Posted by joshuaaewallen

So, if I read that right... The 7189A is a suitable "upgrade" to an EL84, and can handle higher voltage, but... An EL84 may not work that well (or at all) as a replacement for a 7189A?

... I may be reading that wrong. I am waay underslept and amp hopped up on energy drinks right now...

I'm not sure, either. I'm going to venture a guess and say that if you look at your tube socket, so long as you don't have anything connected to pin 1 or pin 6, you should be able to use the 7189A. Don't take this as a fact - it may be completely ass-backwards. Then, there's always the reliability (or lack thereof) of what you read online. I usually go by the rule that if you're not sure, don't.

MartyStrat54 · 06-14-2009, 04:46 PM

You can replace a 6BQ5/EL84 directly with a 7189, but not the other way around.

The 7189A is wired differently internally, but it is still listed as a substitute for a 7189 (and 6BQ5/EL84).

The 7189 has the same "pin-out" as the 6BQ5/EL84. The 7198A will work in the same pin-out, if it has been determined to be safe to do so. Otherwise, some rewiring on the tube bases will be necessary.

The 6BQ5/EL84 works with plate voltage up to 300-330V(max).

The 7189 works with plate voltage up to 400V.

The 7189A works with plate voltage exceeding 400 volts.

7189's have always been called 6BQ5's on steroids. When used as a 6BQ5, they last forever, because they are designed for higher plate voltages.

Josh, you have the 7189A's, because they were the newer (better) tube at the time the Hi-Fi unit was made.

Marty

joshuaaewallen · 06-14-2009, 06:49 PM

Hey Marty,

I finally had an hour or so today to wail away on these two baby's with a fresh set of strings. Holy Crap what a sweet sound! Other than a few minutes on the clean channel (I always power-up and come off standby on the clean channel), I pretty much stayed on the lead channel for at least an hour. It's gonna be tough to try anther combination because this one just feels sooo good. There is a lot more definition of my notes with this setup. I actually was playing my guitar on this channel (rolling back the volume to varying levels... using different pick-ups). On just my lead channel I can conjure up clean jangle, clean warm, ac/dc crunch, skynyrd's "gimme three steps", nazereth's "hair of the dog", and then moved on into Def Leppard, The Donna's, and some "Enter Sandman". This is a very sweet set-up. The highs are there, but they aren't harsh and ear wrecking. The mids are more pronounced than I'm used to, but actually they aren't overwhelming and lend themselves nicely to classic and heavy rock. The bass is pretty tight. I actually liked it plenty w/ out using the deep switch at all. I've never spent so much time just pulling great tones out of my high-gain channel before. I've always just set up my two or three channels and switched between them for my different tones.

Oh how sweet it is!

V1:

V2:

I'll have to give it a good run through on the clean & crunch channel's too before I move on to a different combination. I have to be fair and try 'em in all their uses...

MartyStrat54 · 06-14-2009, 09:16 PM

Hey, I don't blame you at all with what you got right now. An RCA 7025 and an Amperex (Holland) 12AX7 with high gain capability. I was just telling old Solar Burn that sometimes a tube that reads 25/25 is the best bet for V1. It gives you that clean "clean." However, back it up with a rocket in V2 and no one can accuse you of not having a high gain amp. I am sending him some 7025's to try out as well as some more 12AX7's.

I might as well have you guys try them out and find what you like on your own.

Marty

solarburnDSL50 · 06-14-2009, 10:45 PM

Quote:

Originally Posted by joshuaaewallen

Hey Marty,

I finally had an hour or so today to wail away on these two baby's with a fresh set of strings. Holy Crap what a sweet sound! Other than a few minutes on the clean channel (I always power-up and come off standby on the clean channel), I pretty much stayed on the lead channel for at least an hour. It's gonna be tough to try anther combination because this one just feels sooo good. There is a lot more definition of my notes with this setup. I actually was playing my guitar on this channel (rolling back the volume to varying levels... using different pick-ups). On just my lead channel I can conjure up clean jangle, clean warm, ac/dc crunch, skynyrd's "gimme three steps", nazereth's "hair of the dog", and then moved on into Def Leppard, The Donna's, and some "Enter Sandman". This is a very sweet set-up. The highs are there, but they aren't harsh and ear wrecking. The mids are more pronounced than I'm used to, but actually they aren't overwhelming and lend themselves nicely to classic and heavy rock. The bass is pretty tight. I actually liked it plenty w/ out using the deep switch at all. I've never spent so much time just pulling great tones out of my high-gain channel before. I've always just set up my two or three channels and switched between them for my different tones.

Oh how sweet it is!

V1:

V2:

I'll have to give it a good run through on the clean & crunch channel's too before I move on to a different combination. I have to be fair and try 'em in all their uses...

Looks like a great combo there in V1 & V2. I can't wait to try the 7025 in V1 along with the other ones I'll be demoing. Guitar rolling off into semi-cleans or clean on the lead channel and still get all those other gain textures is awesome! Better write down which ones you like the best in what positions. You gotta lotta tubes...

joshuaaewallen · 06-14-2009, 10:51 PM

Quote:

Originally Posted by solarburnDSL50

... Guitar rolling off into semi-cleans or clean on the lead channel and still get all those other gain textures is awesome! Better write down which ones you like the best in what positions. You gotta lotta tubes...

... No kidding mate! Right now I am actually up to my ears (literally & figuratively

) in tubes to try out!

I think you're gonna like the 7025 & high gain experience. Marty definitely ain't talkin' out of his rear on that one. This combo just plain works! <Marty... You Da Man!>

Well... This rocker's gonna hit the hay, so ya'll have a good night, and we'll talk at ya later!

solarburnDSL50 · 06-15-2009, 11:12 PM

Quote:

Originally Posted by joshuaaewallen

... No kidding mate! Right now I am actually up to my ears (literally & figuratively

) in tubes to try out!

I think you're gonna like the 7025 & high gain experience. Marty definitely ain't talkin' out of his rear on that one. This combo just plain works! <Marty... You Da Man!>

Well... This rocker's gonna hit the hay, so ya'll have a good night, and we'll talk at ya later!

Haha! You should see what Marty is doing to me tube wise. Whoo Hoo! I'm going to be in the same boat as you, writing down them combination's...

RiverRatt · 06-16-2009, 11:50 AM

Got a few leads on some old stuff. I found an old RCA Victor 45 RPM record player. It's in a brown bakelite housing with no way to see the amp - seller asking $45. Found an RCA Victor radio that only has three tubes in it - the only useful one looks to be a Sylvania 12AT7 - asking $15. Found a Kodak Pageant 126 film projector with sound. Not a lot of info. on the web about this projector. I'm reasonably sure it's old enough that it's all tube - seller asking $32. Any of this sound like it's worth the $$$?

On a side note, during my quest for tubes, my wife said "You know, my mother has one of those big console phonograph/radio combos, and an old portable record player." Now, I'm not sure about the date on any of this, but guessing, I'd say it's probably late 50's stuff. She said I could have the portable if she can find it, but she doesn't want to scrap the console, as it still works fine. I'm still going to see if she'll let me pull the back off and take a peek inside.

MartyStrat54 · 06-16-2009, 02:20 PM

Quote:

Originally Posted by RiverRatt

Got a few leads on some old stuff. I found an old RCA Victor 45 RPM record player. It's in a brown bakelite housing with no way to see the amp - seller asking $45. Found an RCA Victor radio that only has three tubes in it - the only useful one looks to be a Sylvania 12AT7 - asking $15. Found a Kodak Pageant 126 film projector with sound. Not a lot of info. on the web about this projector. I'm reasonably sure it's old enough that it's all tube - seller asking $32. Any of this sound like it's worth the $$$?

On a side note, during my quest for tubes, my wife said "You know, my mother has one of those big console phonograph/radio combos, and an old portable record player." Now, I'm not sure about the date on any of this, but guessing, I'd say it's probably late 50's stuff. She said I could have the portable if she can find it, but she doesn't want to scrap the console, as it still works fine. I'm still going to see if she'll let me pull the back off and take a peek inside.

CONSOLE...50's...ALL TUBE. Take the back off and at least tell us what is in it. Maybe it's a 6V6 amp. Some of the good one's had a bass amp and two treble amps. Tubes, tubes tubes. It's a shame all you can do is lookey, no touchey. (May be a mono amp.)

As far as that other stuff, without pictures and a description of the components, it's hard to say what they are worth. I know some projectors had a 5U4GB, (2) 6L6's and (2) 12AX7 tubes. That would just cover the $32 dollars if the tubes were all RCA or Tung-Sol and "good." The free portable is probably going to have a stereo (or is it mono?) single ended amp with 6BQ5's. These are old enough that they might be mono players. Stereo really didn't hit the scene until the early sixties.

The 45 RPM player might have a really odd power amp as many of them did. It might have one or two 12AX7's in it, but the power tubes could be almost anything. For $45 dollars, I'm buying five 12AX7's on EBAY, or two hot brand ones like Amperex or Mullard.

When this old stuff still works you hate to tear it up and the seller is wanting more money. It's best to find DOA gear and then all you are interested in is the tubes and usable parts. I've found many a good power tranny for 6BQ5 amps etc. Let me know what you find out in the big console and the portable.

Marty

solarburnDSL50 · 06-18-2009, 03:19 AM

I just got a 412 loaded with Greenbacks. Now I have to roll all those tubes again...not!

MartyStrat54 · 06-18-2009, 09:02 PM

CONGRATULATIONS!!!

Over 6,000 views and almost 500 replies.
YOU GUYS ROCK!

If you have the time, go back and read some of the back pages. There is a lot of good stuff in this thread. All newcomers, you are welcome. We love to roll tubes and that includes the current production tubes as well as New Old Stock.

Besides preamp tubes questions, we will be glad to offer some insight on power tubes as well. Tubes are like buying speakers. What sounds good to me may sound lame to you. However, we can give you advice based on actual usage of many types of tubes. Helping you find your sound is what we do. The right tubes can produce a noticeable change in your amps sound.

Here we are, still going strong!

Marty

RiverRatt · 06-19-2009, 11:49 AM

Since you brought up power tubes, I've been looking to get a pair of RFT/Siemens EL34's to try out. If any of you guys have used them, let me know what your impression was. I don't want to drop $100+ on a pair if they aren't going to offer a noticeable improvement. Right now, I'm using Groove Tubes EL34M Mullard copies, which sound good, but I've never tried NOS EL34's.

MartyStrat54 · 06-19-2009, 02:43 PM

Quote:

Originally Posted by RiverRatt

Since you brought up power tubes, I've been looking to get a pair of RFT/Siemens EL34's to try out. If any of you guys have used them, let me know what your impression was. I don't want to drop $100+ on a pair if they aren't going to offer a noticeable improvement. Right now, I'm using Groove Tubes EL34M Mullard copies, which sound good, but I've never tried NOS EL34's.

This is what I told COOLJUK on page 15:

"Well I can tell you are a knowledgeable glass person yourself. I too use Siemens and have two 100 watt amps glassed with them. Siemens are a hell of a good deal if you want "real" EL34's. I guess right now I have twelve of them and eight are being used. Old, original TESLA's are a good buy for 34's."

**********************

************ *********

The main thing about new vs NOS is that the NOS tubes were designed to handle over 800V on the plates. New tubes handle much less than that. What I hear from NOS 34's is a tighter bass and the overall audio spectrum is airy and clean sounding. $100 bucks is a good price on a pair if they test high. I just got a set of real Mullards for $99 and they are already in one of my 602's. That was a good deal. As long as the tubes test above average, don't be afraid to use NOS tubes. Most of my amps run on NOS glass. I've never been disappointed.

Another thing is what is called "EL34 Rattle." Some new EL34's are designed poorly and if you lightly shake the tube by the base, you will hear a rattle. NOS tubes generally do not do this, or if they do, it is at a minimum. I have bought new 34's before that rattled like crazy. I sent them back for a different set (They were Winged =C='s). You can do a little research on this and you will see what I mean.

However, if you are used to running new tubes, your ears may have become used to "that sound." An NOS tube may or may not blow you away.

Marty

RiverRatt · 06-19-2009, 03:44 PM

Sorry, man. This thing is getting hard to keep up with. I totally missed that exchange.

I don't know enough about old EL34's to know a good deal when I see one. There is a guy on eBay who regularly sells NOS Siemens/RFT EL34's in white boxes for around $100 a pair. I don't know if it's legal to post a link here... If you search eBay for "siemens el34", his are the ones that are $99.99 BIN. Do these look like the real deal? $100 sounds like a very fair price from what I've read.

MartyStrat54 · 06-19-2009, 04:01 PM

Let me do some checking. I think I know who you are talking about.

Marty

MartyStrat54 · 06-19-2009, 04:20 PM

Well someone must have bought them, because I looked through all of the EL34 tubes. I did earmark several auctions that I am interested in so it wasn't a total loss. Check and see if he is still there. If so, let me know his user name.

Marty

MartyStrat54 · 06-19-2009, 06:00 PM

Quote:

Originally Posted by RiverRatt

Since you brought up power tubes, I've been looking to get a pair of RFT/Siemens EL34's to try out. If any of you guys have used them, let me know what your impression was. I don't want to drop $100+ on a pair if they aren't going to offer a noticeable improvement. Right now, I'm using Groove Tubes EL34M Mullard copies, which sound good, but I've never tried NOS EL34's.

I've got a super nice, matched pair of Siemens "Dimple Top" EL34's that I would part with. Email or PM me and we can discuss it further.

Marty

RiverRatt · 06-19-2009, 06:24 PM

Quote:

Originally Posted by MartyStrat54

Well someone must have bought them, because I looked through all of the EL34 tubes. I did earmark several auctions that I am interested in so it wasn't a total loss. Check and see if he is still there. If so, let me know his user name.

Marty

bmsanborn. Says he still has 3 sets at that BIN price.

joshuaaewallen · 06-19-2009, 07:59 PM

Quote:

Originally Posted by MartyStrat54

Hey, I don't blame you at all with what you got right now. An RCA 7025 and an Amperex (Holland) 12AX7 with high gain capability. I was just telling old Solar Burn that sometimes a tube that reads 25/25 is the best bet for V1. It gives you that clean "clean." However, back it up with a rocket in V2 and no one can accuse you of not having a high gain amp. I am sending him some 7025's to try out as well as some more 12AX7's.

I might as well have you guys try them out and find what you like on your own.

Marty

V1:

V2:

I've gotta tell ya Marty... I am in love with this combination. It is just superb in every channel.

The clean channel is just warm, sparkly goodness at every setting, in every pickup position. From jangly, to warm, to almost acoustic. Just a sweet, sweet tone.

The crunch channel IS classic rock. I can hit everything from clean to fairly high gain all on that channel. Setting the gain around 7 or 8 I get nice classic rock crunch and roll back the guitars volume for between that and clean. And oh so textured. Love it!

And of course you already know how I feel about how my lead channel responds w/ these tubes. Oh yeah!

So...

I know I'm digging this pairing. BIG TIME!

So for my next round of test subjects, what do you think... Keep the 7025 in V1 and start trying different 12AX7's in V2? Or keep the Dutch Treat in V2 and start trying different tubes in V1?

MartyStrat54 · 06-19-2009, 09:34 PM

Keep that nice Amperex in V2 and try a stouter 7025 and see if that disrupts the clean channel. If not, get a feel for it and then try the crunch channel and see if you still have consistency with your crunch.

I've got to tell you that what you got right now is almost verbatim for what I'm running in all of my amps. That's the combo I came up with, a medium gain 7025 in V1 and a high gain in V2. That Amperex is one sweet tube. It has as many write ups and recognition as the RFT and the Tungsram. Right now, a Bugle Boy (Amperex) 12AX7 can easily go for $100 or more per tube.

Those two tubes will give you consistent sound for a minimum of two years. I'd say more like three to four years. They don't make them like that anymore.

Also, wouldn't you say that the "new" Blackburn (Mullard) tubes have gone down the drain. Our emails weren't returned, the economy is bad. I say they aren't going to get out of the gate. You have to put your faith in NOS. I mean I know you're a believer. You've heard firsthand what a good set of tubes can do...right?

Don't rip yourself apart with all those other tubes. If you found the clean cleans and the crunch and lead you really like, then go with it.

Marty

MartyStrat54 · 06-19-2009, 09:52 PM

Quote:

Originally Posted by RiverRatt

bmsanborn. Says he still has 3 sets at that BIN price.

Well, I spent an hour on EBAY and I can't find this seller. I searched under his name in the tube section and it came up zero. You are going to have to put down the auction number so I can look it up that way. Sorry.

Marty

joshuaaewallen · 06-19-2009, 10:22 PM

Quote:

Originally Posted by MartyStrat54

Keep that nice Amperex in V2 and try a stouter 7025 and see if that disrupts the clean channel. If not, get a feel for it and then try the crunch channel and see if you still have consistency with your crunch...

Sounds good. I'll have a go at that then. Either way... This first combo is the beez kneez. I'll be on that like a fly on crap if nothing else floats my boat!

Quote:

Originally Posted by MartyStrat54

... I've got to tell you that what you got right now is almost verbatim for what I'm running in all of my amps. That's the combo I came up with, a medium gain 7025 in V1 and a high gain in V2. That Amperex is one sweet tube. It has as many write ups and recognition as the RFT and the Tungsram. Right now, a Bugle Boy (Amperex) 12AX7 can easily go for $100 or more per tube.

Those two tubes will give you consistent sound for a minimum of two years. I'd say more like three to four years. They don't make them like that anymore...

... You've heard firsthand what a good set of tubes can do...right?

It really is astounding the difference a good set of tubes makes. It is just night and day. It's like color verses black and white. Just amazing.

Quote:

Originally Posted by MartyStrat54

... Also, wouldn't you say that the "new" Blackburn (Mullard) tubes have gone down the drain. Our emails weren't returned, the economy is bad. I say they aren't going to get out of the gate. You have to put your faith in NOS. I mean I know you're a believer. You've heard firsthand what a good set of tubes can do...right?

Yeah... I think our friends at the Blackburn plant are crashing before they leave the runway. Bummer too. I was looking forward to a current production tube that could stand above the crowd. Too bad.

Quote:

Originally Posted by MartyStrat54

... Don't rip yourself apart with all those other tubes. If you found the clean cleans and the crunch and lead you really like, then go with it.

I'm not gonna stress over it, but I figure I'll try more pairings and see where it takes me. Maybe the holy grail is still out there. Who knows?

joshuaaewallen · 06-19-2009, 10:26 PM

Quote:

Originally Posted by MartyStrat54

Well, I spent an hour on EBAY and I can't find this seller. I searched under his name in the tube section and it came up zero. You are going to have to put down the auction number so I can look it up that way. Sorry.

Marty

Try this: eBay Seller: bmsanborn: Musical Instruments items on eBay.com

joshuaaewallen · 06-19-2009, 10:38 PM

Here's a dumb question... Is a 12AX7A the same as a 7025?

joshuaaewallen · 06-19-2009, 10:48 PM

Quote:

Originally Posted by solarburnDSL50

... I found 1 dealer that has Anos RCA 12AX7A's and he wants $48 for one and they are used but test like new. Otherwise I'm not seeing much of a selection from my places as far as these go.

Is this something you're interested in? 12AX7A by Rca - Buy or Repair at PLCCenter

06-14-2009, 11:56 AM	#481 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 7,222	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? That picture looks like it's a 7189 Sylvania. If so, it should be good to go in an EL84 amp. Scratch that. I just took another look at the picture and it is a 7189A. Bad luck there. Still, take a look at that second link I found before you give up hope.

06-14-2009, 01:49 PM	#482 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Looks like the unit was made around 1962. That's the date code showing on the 7189A. Too bad they weren't 7189's. I looked at the prices and then I looked at what he was asking for EL34's. Holy crap...those are "each" prices and not per pair. I think I did real good on my xf4's for $99. Not to mention they tested NOS. It's been a while since I've been to that site. It's amazing how many tube brokers are out there and how many tubes are still left, if you've got the cash. He also made the comment that GE was the only company that made the 7189A. If he really knew his tubes (and tube identification), he would know that good old Sylvania made the tubes for GE. (As I said, by the late 50's and early 60's, it was common for GE to have Sylvania make several dozen types of tubes for them and have them labeled GE. Everybody was wanting to get out of the tube business. That's why there are some damn good Japanese tubes out there. Sylvania kept their tube plants open longer than RCA.) Marty Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-14-2009, 04:46 PM	#487 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? You can replace a 6BQ5/EL84 directly with a 7189, but not the other way around. The 7189A is wired differently internally, but it is still listed as a substitute for a 7189 (and 6BQ5/EL84). The 7189 has the same "pin-out" as the 6BQ5/EL84. The 7198A will work in the same pin-out, if it has been determined to be safe to do so. Otherwise, some rewiring on the tube bases will be necessary. The 6BQ5/EL84 works with plate voltage up to 300-330V(max). The 7189 works with plate voltage up to 400V. The 7189A works with plate voltage exceeding 400 volts. 7189's have always been called 6BQ5's on steroids. When used as a 6BQ5, they last forever, because they are designed for higher plate voltages. Josh, you have the 7189A's, because they were the newer (better) tube at the time the Hi-Fi unit was made. Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-14-2009, 06:49 PM	#488 (permalink)
joshuaaewallen Senior Member Join Date: Jan 2009 Location: The Dark Side Of The Moon Posts: 1,346	Re: Preamp Tubes? - New Strings Hey Marty, I finally had an hour or so today to wail away on these two baby's with a fresh set of strings. Holy Crap what a sweet sound! Other than a few minutes on the clean channel (I always power-up and come off standby on the clean channel), I pretty much stayed on the lead channel for at least an hour. It's gonna be tough to try anther combination because this one just feels sooo good. There is a lot more definition of my notes with this setup. I actually was playing my guitar on this channel (rolling back the volume to varying levels... using different pick-ups). On just my lead channel I can conjure up clean jangle, clean warm, ac/dc crunch, skynyrd's "gimme three steps", nazereth's "hair of the dog", and then moved on into Def Leppard, The Donna's, and some "Enter Sandman". This is a very sweet set-up. The highs are there, but they aren't harsh and ear wrecking. The mids are more pronounced than I'm used to, but actually they aren't overwhelming and lend themselves nicely to classic and heavy rock. The bass is pretty tight. I actually liked it plenty w/ out using the deep switch at all. I've never spent so much time just pulling great tones out of my high-gain channel before. I've always just set up my two or three channels and switched between them for my different tones. Oh how sweet it is! V1: V2: I'll have to give it a good run through on the clean & crunch channel's too before I move on to a different combination. I have to be fair and try 'em in all their uses... __________________ Josh -2004 PRS Custom 24 10 Top (Sustainiac System w/ Duncan Alnico II bridge PickUp) -1999 Marshall JCM 2000 TSL (Wilder Amplification mods) -Martimus Maximus Preamp Tone Pack (Rollin' With Da Homie's) -ElectroHarmonix .44 Magnum -PRS Dallas 120 2x12 Vintage 30's -Digitech RP1000

06-14-2009, 09:16 PM	#489 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Hey, I don't blame you at all with what you got right now. An RCA 7025 and an Amperex (Holland) 12AX7 with high gain capability. I was just telling old Solar Burn that sometimes a tube that reads 25/25 is the best bet for V1. It gives you that clean "clean." However, back it up with a rocket in V2 and no one can accuse you of not having a high gain amp. I am sending him some 7025's to try out as well as some more 12AX7's. I might as well have you guys try them out and find what you like on your own. Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

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06-16-2009, 11:50 AM	#493 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 7,222	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Got a few leads on some old stuff. I found an old RCA Victor 45 RPM record player. It's in a brown bakelite housing with no way to see the amp - seller asking $45. Found an RCA Victor radio that only has three tubes in it - the only useful one looks to be a Sylvania 12AT7 - asking $15. Found a Kodak Pageant 126 film projector with sound. Not a lot of info. on the web about this projector. I'm reasonably sure it's old enough that it's all tube - seller asking $32. Any of this sound like it's worth the $$$? On a side note, during my quest for tubes, my wife said "You know, my mother has one of those big console phonograph/radio combos, and an old portable record player." Now, I'm not sure about the date on any of this, but guessing, I'd say it's probably late 50's stuff. She said I could have the portable if she can find it, but she doesn't want to scrap the console, as it still works fine. I'm still going to see if she'll let me pull the back off and take a peek inside.

06-18-2009, 09:02 PM	#496 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? CONGRATULATIONS!!! Over 6,000 views and almost 500 replies. YOU GUYS ROCK! If you have the time, go back and read some of the back pages. There is a lot of good stuff in this thread. All newcomers, you are welcome. We love to roll tubes and that includes the current production tubes as well as New Old Stock. Besides preamp tubes questions, we will be glad to offer some insight on power tubes as well. Tubes are like buying speakers. What sounds good to me may sound lame to you. However, we can give you advice based on actual usage of many types of tubes. Helping you find your sound is what we do. The right tubes can produce a noticeable change in your amps sound. Here we are, still going strong! Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-19-2009, 11:49 AM	#497 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 7,222	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Since you brought up power tubes, I've been looking to get a pair of RFT/Siemens EL34's to try out. If any of you guys have used them, let me know what your impression was. I don't want to drop $100+ on a pair if they aren't going to offer a noticeable improvement. Right now, I'm using Groove Tubes EL34M Mullard copies, which sound good, but I've never tried NOS EL34's.

06-19-2009, 03:44 PM	#499 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 7,222	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Sorry, man. This thing is getting hard to keep up with. I totally missed that exchange. I don't know enough about old EL34's to know a good deal when I see one. There is a guy on eBay who regularly sells NOS Siemens/RFT EL34's in white boxes for around $100 a pair. I don't know if it's legal to post a link here... If you search eBay for "siemens el34", his are the ones that are $99.99 BIN. Do these look like the real deal? $100 sounds like a very fair price from what I've read.

06-19-2009, 04:01 PM	#500 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Let me do some checking. I think I know who you are talking about. Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-19-2009, 04:20 PM	#501 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Well someone must have bought them, because I looked through all of the EL34 tubes. I did earmark several auctions that I am interested in so it wasn't a total loss. Check and see if he is still there. If so, let me know his user name. Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-19-2009, 09:34 PM	#505 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Now in Muskogee, by Tulsa Posts: 18,271	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Keep that nice Amperex in V2 and try a stouter 7025 and see if that disrupts the clean channel. If not, get a feel for it and then try the crunch channel and see if you still have consistency with your crunch. I've got to tell you that what you got right now is almost verbatim for what I'm running in all of my amps. That's the combo I came up with, a medium gain 7025 in V1 and a high gain in V2. That Amperex is one sweet tube. It has as many write ups and recognition as the RFT and the Tungsram. Right now, a Bugle Boy (Amperex) 12AX7 can easily go for $100 or more per tube. Those two tubes will give you consistent sound for a minimum of two years. I'd say more like three to four years. They don't make them like that anymore. Also, wouldn't you say that the "new" Blackburn (Mullard) tubes have gone down the drain. Our emails weren't returned, the economy is bad. I say they aren't going to get out of the gate. You have to put your faith in NOS. I mean I know you're a believer. You've heard firsthand what a good set of tubes can do...right? Don't rip yourself apart with all those other tubes. If you found the clean cleans and the crunch and lead you really like, then go with it. Marty __________________ MARTY MARTIMUS MAXIMUS ONLINE TUBES AND OTHER STUFFHyperlink Wilder modded JCM 2204 (Sold my JMP to Joe.). Many other amps. Strats and Explorer are my main guitars.

06-19-2009, 10:38 PM	#509 (permalink)
joshuaaewallen Senior Member Join Date: Jan 2009 Location: The Dark Side Of The Moon Posts: 1,346	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Here's a dumb question... Is a 12AX7A the same as a 7025? __________________ Josh -2004 PRS Custom 24 10 Top (Sustainiac System w/ Duncan Alnico II bridge PickUp) -1999 Marshall JCM 2000 TSL (Wilder Amplification mods) -Martimus Maximus Preamp Tone Pack (Rollin' With Da Homie's) -ElectroHarmonix .44 Magnum -PRS Dallas 120 2x12 Vintage 30's -Digitech RP1000 Last edited by joshuaaewallen; 06-20-2009 at 07:56 AM.

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