Got the 2 channel set up now a tube rolling ?

[USNRET]

First off if this should be elsewhere sorry, I DID think about it anyway. Second get over the typos as I'm sure there will be some. Thirdly, this will eventually get to a question about difference in tubes in an amp so bare with a some background.

Ok, I have been moving around the house as I tried to take control of the kids room with Khorns (thanks Joe, I finally got to sample this model and quickly found that you must have the house, I don't. Hope Bob has better luck). I got kicked out of there and went back to the basement and plugged everthing back in yesterday. WOW, I've never heard anything as good as this. So if it's that good why am I asking questions? Well, I guess because it's there and that's why we are on here.

I have the following in this system:

Pro_Ject RM-5SE (Sumiko Blue Point 2 factory installed) with a Juicy Music Tercel providing power to an original Peach that has been updated by Mark and then on to a VRD stereo amp (I'm told stock Valve Art KT-88s). Speakers are Belles w/ BEC CT-125 tweeters, A4500 xovers and push-pull K-55s. 35 feet of home depot 12 gauge speaker wires that are turning a nice green color under the clear insulation but the conductor is clean at the connections.

I am just getting to know the system and plan to listen for a while attempting to learn it before I do squat. I have an two additional sets of tubes for the VRD and my question is what would I expect to happen to the sound when I plug in the different tubes I acquired with the amp. I have a set of Valve Art 305Bs marked with a sticker that says "70" on the box and a set of Gold Loin KT-88s with a sticker on the box (all 4) that says lp: 76 and GM 8300.

Any thoughts on any sound change I would be expecting? I have the bias set at 0.57 with the stock VA KT-88s.

[russ69]

If you want to bring the mid range out a bit, I'd try a set of EL-34s if the amp can do that. Also some solid copper speaker wire will smooth the sizzle a little if that's the way you want to go.

Thanx, Russ

[Gilbert]

I belive the bias should be 0.7V with the KT88's. Not sure what your question is though.

[Daddy Dee]

usnret,

very nice system bro.

I'm no help on suggestions for tube rolling, but the flavors can be fun.

[SilverSport]

USNRET,

Set your bias at .70 for those OE Valve Arts...unless you have had the latest update from Craig and that is the lower bias his update allows...I am using OE Valve Arts with mine and they sound very good (my VRDs are at Craig's for the update and a going over)...I am by no means an expert nor a Tube Roller...my VRDs came with two sets of Tubes...NOS Tubes with the power tubes being Ei KT-90s...I liked these but they wouldn't hold bias...as for sound...I found TONS of bass and lucious mids but the highs could get shrill or ragged...I then tried the other pair I got with mine which were Electro Harmonix KT-88s...don't waste your money on these...kinda thin I thought...the Valve Arts are a nice compromise...

If you ask Craig, he won't tell you anything prefering to let you be the judge...I thought that was a great way to go...not coloring my thoughts on the Tubes and when I told him what I thought of them, he said I had a good ear...regardless...give your others a try...

Bill

[USNRET]

Set your bias at .70 for those OE Valve Arts

Thanks, not knowing any better, I thought I'd ease into the bias. Appreciate the info all, I know it's very subjective but I thought I'd see what other ears had heard. Gotta get some time on the system to learn the differences from the McIntosh stuff. I just picked up the Thorens 125 anniversery LP and I'm using it for a 'standard'.

[frankphess]

I'm sure Craig may chime in, but with the KT-88's the bias should be set to .70 as has been stated. When using 350B's (not 305B) you should change the rectifiers to 5U4G type, and set the bias from .40-.55. I used to set mine at .52. If you want to try different tubes, I would experiment with different signal tubes. The 6DJ8 in the V1 slot of the Peach should be your best 6DJ8 you own, V2 & V3 not as important, but should match (with the Peach in HIZ mode). In the amplifer, I would experiment with different12AX7/12AU7's. Changing signal tubes will result a more noticeable change for better or worse. Changing power tubes, for me, was difficult to discern much difference unless of course you have a tube popping or making noise. I've found NOS signal tubes from Brent Jesse lowers the noise floor considerably.

[Coytee]

Any thoughts on any sound change I would be expecting?

I'd listen to these other guys. I don't know any ideas relative to your paramaters mentioned above however, just to give you an experience I had.

I once had a Jolida 502A (or was it a 501A?)

Regardless... used KT-88 tubes. Someone here on the forum said to try some KT-90's as they'd give more weight to the bass. I bought a set and put them in... he was right. There was clearly more oomph to the sound (which I liked).

It's interesting to me how different tubes can flavor the sound. Good luck finding your bliss!!

[USNRET]

Again thanks for the inputs. I have several sets of small (input/rectifier?) tubes as well. As soon as I get cleaned up around here for some surprise guests arriving I willl post what I have so you guys can set me straight on what goes together, don't want to screw this up.

[USNRET]

Finally got a little time around here. Bachelor pad for the week as the wife has taken the inlaws and kids to S. Carolina for the week. I am supposed to be painting my daughter's room but, hey it's quite and I have Marshall Tucker on the TT.

OK, first I took the VRD_ST's bias with Valve Art KT-88s (JJ ECC83s, JJ ECC 82 and Sovtek 5AR4) up to 0.70 as recommended here. I found it harsh and am now have it back to 0.60, much more mellow. Question 1: How would you EXPECT the bias increase / decrease to affect sound? Tube life? Other pros and cons to bias change?

I said I would post a list of tubes that I have in hand (and some installed info). I need, in some format my dumb a** can read, understand and save, someone to guide me on what tubes match what. I'll also solicite thought on any experience on what tubes do what to sound. Again, I need a lot more time on the stock setup so I can 'periment and have a gauge/standard.

Tercel has: 3 Electro Harmonix 12AX7EH with what I assume is a date stamp of 08 01

VRD_ST has Valve Art KT-88s ("matched" per sticker on the boxes); JJ ECC83s, JJ ECC 82 and Sovetek 5AR4

Peach (didn't open it to see what's there but I asked Mark to do what he thought best when I sent the preamp in 6-7 months ago to get it re-freshed)

Here are the tubes I have collected as either package deal on th ebuy or as removed as stock on the Peach and Jolida JD100A:

2 ea RCA 12AX7A from Brent Jesse Production Type "A" marked 1500/1500 Dated 10-17-08

2 ea. RCA 12AU7A "Cleartop" dated 10-21-08

3 ea. Ei 6DJ8EG (IIRC removed from Peach)

1 ea. unknown 12X4

2 ea. Electro Harmonix 12AX7A (removed from the Jolida by Hotrodaudiomods when they modded mine new)

4 ea. Valve Art 350Bs, boxes are taped together and marked on end of box 1 thru 4 w/marker and a round yellow sticker that has "70" written on it.

4 ea Gold Loin KT-88sw/ a sticker that says lp:76 & Gm:8300 on each box.

What goes with what in the VRD, etc.

Thanks, boys and girls!

Mike

[mark1101]

Valve Art KT-88s are great sounding and especially for the money. But if you have a set of Genelax Gold Lion KT-88s........those should be better. Many say that those are the very best KT-88s out there. They sure cost enough. Check the prices......more than double the Valve Arts. I'd at least give them a try.