So I finally got around to swapping out some tubes in my pre-amp
headrott
Posts: 5,496
OK, first some info on what tubes I had in the pre-amp. the pre-amp is an AMC CVT-1030as and it used 2 12AX7s and 2 12AU7s. The ones I've hade in there (for about the last 5 years now) were 2 Valvo 1958 45 degree halo-getter tubes I got from Brent Jesse about 6 years ago. The 12AU7s were 2 Brimar 14D5s (so actually they weren't really 12AU7s, but equivalent tubes and you get the point).
First, impressions on how the Valvo and Brimars sound. These tubes are very smooth sounding together. I think this mostly comes from the Brimars as they are like Mullards to a large degree. The Brimars have a nice high end without being harsh at all and a relatively good low end. They do "mess" with the sound a little by warming up the midrange and high end, but not too much (IMO). The Valvos are much like Siemens tubes, but better than the Siemens 12AX7s, at least the 45 degree angle halo getters are (IMO). They have a great extension of the high and low and are also not harsh at all. They match well with the Brimars because they are more sterile sounding, but revealing. they don't add a lot of warmth to the signal, but are relatively detailed. I thought these tubes had a relatively large soundstage and 3-D sound, until I switched tubes..........
I then switch both sets of tubes out for some Amperex "Bugle Boy" 12AX7s and RCA "clear top" 12AU7s. OK, let me say that this combination is rediculously good. The soundstage opened up both width and depth about another 3 feet (literally). I was blown away at how big the soundstage is with these tubes! SDA to the max! The bugle boys have a little better low end extension than the Valvos, but only barely. The bass is not as tight as the Valvos though. The highs are definately a little more harsh with the Bugle Boy/RCA clear top combo. Definately not warm like the Brimar/Valvo combo, but not completely sterile either. Relatively different sounding tones from the Bugle Boy/RCA clear top combo. I played a lot of Hendrix with both tubes to compare and overall the tones from the Valvo/Brimar combo won out, but I could not escape the need for the soundstage from the Bugle Boy/RCA combo. Especially when listening to "Electric Ladyland" I was floored by how ".....and the gods made love" sounded. If sounded like you were in a tornado because the audio enveloped you so much depth and width-wise. Also, the Bugle Boy/Clear Top combo brought out a little more detail than the Brimar/Valvo combo did, but not by much.
So, if you have a pre-amp that uses 12AX7s and 12AU7s get a pair of Bugle boys and clear tops to throw in there. You will be extrememly happy you did. If you want a more warm sound try out the Valvo/Brimar combo. You will get more warmth, and have a smoother sound, but will have a smaller soundstage, and lose a little detail.
Greg
First, impressions on how the Valvo and Brimars sound. These tubes are very smooth sounding together. I think this mostly comes from the Brimars as they are like Mullards to a large degree. The Brimars have a nice high end without being harsh at all and a relatively good low end. They do "mess" with the sound a little by warming up the midrange and high end, but not too much (IMO). The Valvos are much like Siemens tubes, but better than the Siemens 12AX7s, at least the 45 degree angle halo getters are (IMO). They have a great extension of the high and low and are also not harsh at all. They match well with the Brimars because they are more sterile sounding, but revealing. they don't add a lot of warmth to the signal, but are relatively detailed. I thought these tubes had a relatively large soundstage and 3-D sound, until I switched tubes..........
I then switch both sets of tubes out for some Amperex "Bugle Boy" 12AX7s and RCA "clear top" 12AU7s. OK, let me say that this combination is rediculously good. The soundstage opened up both width and depth about another 3 feet (literally). I was blown away at how big the soundstage is with these tubes! SDA to the max! The bugle boys have a little better low end extension than the Valvos, but only barely. The bass is not as tight as the Valvos though. The highs are definately a little more harsh with the Bugle Boy/RCA clear top combo. Definately not warm like the Brimar/Valvo combo, but not completely sterile either. Relatively different sounding tones from the Bugle Boy/RCA clear top combo. I played a lot of Hendrix with both tubes to compare and overall the tones from the Valvo/Brimar combo won out, but I could not escape the need for the soundstage from the Bugle Boy/RCA combo. Especially when listening to "Electric Ladyland" I was floored by how ".....and the gods made love" sounded. If sounded like you were in a tornado because the audio enveloped you so much depth and width-wise. Also, the Bugle Boy/Clear Top combo brought out a little more detail than the Brimar/Valvo combo did, but not by much.
So, if you have a pre-amp that uses 12AX7s and 12AU7s get a pair of Bugle boys and clear tops to throw in there. You will be extrememly happy you did. If you want a more warm sound try out the Valvo/Brimar combo. You will get more warmth, and have a smoother sound, but will have a smaller soundstage, and lose a little detail.
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
![:\](https://forum.polkaudio.com/resources/emoji/confused.png ":\"){kind=small}
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee
Post edited by headrott on
Comments
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I love reading tube reviews, thanks for posting it.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
You bet Jesse. I love reading them too, but not as much as listening to them.:D I will post a review of the BAT VK-3i with the tubes that come with it (Sovtec 6922s and National Electronics (SED) 6V6 tubes). i am also getting some 1958 Amperex Bugle Boys ECC88 D-getter tubes to put into it. I cannot wait to hear them in the BAT! I will post a review on Thursday probably.
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
Great review,, the "other" good thing about the RCA cleartops,is that they are still affordable.Some of the best/inexpensive ones can be had from "organ pulls".JC approves....he told me so. (F-1 nut)
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soon....
very soon....
I will have a Tube Pre and I'll be able to roll some tubes!
I can't wait!
Sal,
What pre-amp are you thinking of getting?
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
george daniel wrote: »Great review,, the "other" good thing about the RCA cleartops,is that they are still affordable.Some of the best/inexpensive ones can be had from "organ pulls".
That is an excellent point George. They are very cheap, comparitively to other tubes from the same era. I wish the bugle boys were as cheap as the clear tops.....:(
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
It looks like it uses the 6dj8/6922/7803 tubes in it. There are some good ones out there. Unfortunately they are some of the most expensive I am learning. I just bought some Amperex bugle boy ECC88(6DJ8) 1958 D-getter tubes that cost $230.00 for 4.:eek: And that was a relatively good deal.... I've read these are some of the best ECC88s out there though. I'll find out on thursday.
The regular (LARGE) halo-getter (NOT small) bugle boy 6DJ8/ECC88 tubes are also very good and can be had for a little cheaper ($100 to $120.00 a quad). There are many other options as well. Siemens 1960's ECC88s, Mullards are some popular ones. The Siemens are very good. If you go with 6922's there are many options as well. Amperex orange and white label "PQ" tubes are good. The Siemens 1960's and early 1970's are good. Also, I have heard them, but have read the CCa's are extremely good. May be labeled Siemens, Valvo, or Telefunken.
Just be prepared to spend money.;)
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
I've only heard the 12AX7 mullards and thought they were good, but a little too warm and silky for me.
Never heard the 6922 version though. I've heard they are good. And if you already have heard them, sounds good to buy them. Literally.
What version of mullards are they? ECC88, E88CC, or 7803?
Greg
Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
"I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion."
My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....
"Green leaves reveal the heart spoken Khatru"- Jon Anderson
"Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee -
Drew (NJPOLKER) has a 1L and he bought (4) Mullards for around $100 each and they made the Pre-amp sound Incredible. When I get the 2L he's coming over with his Mullards and I will try them out before buying a set for myself.
I already planned on spending $400 on tubes.
Hey Sal,
Not that's its a big deal but my pre-amp is the Anthem PRE2L. Mullards and Mazda tubes.
