Dared MC-7P preamp.....

HRDROKN

Just received my Dared MC-7P preamp and after a couple minor problems unrelated to the pre... she's up and running!

So I had to do a little amp shuffling as I lost my Carver M1.0t MKII .002 that was driving my LF. The thing that sucks is just THAT change was going to change the sound. Good thing I had spent much time with both amps and had a good grasp on their sound.

Back to the Dared pre... I let her warm up for an hour (stock tubes) this morning before setting down for a listen. Put in some Neil Young...

Although changes are suttle in some areas... the vocal range is the biggest change, wider presentation (I thinking I can play with speaker placement some more now), just a little more warmth. So I put in some Stevie Ray Vaughn and had the same impressions.

The highs sound more detailed or crisp, kinda not where I wanted to be with horns, but then again... stock tubes.

I kinda want (no I do) to change out some tubes already... maybe I'll listen for a couple more hours, then give it a shot. I have new tubes for all positions so I'll have take a guess at which to start with.

HRDROKN

Do you guys let the tubes cool before changing?

HRDROKN

K... changed out:

5UG4 with RCA NOS
12at7 with Mullard NOS
6V6 with RCA from Brent Jessee

I'll do the 12AX7's later.

:cool:

george daniel

HRDROKN wrote: »

Do you guys let the tubes cool before changing?

Nah,, just grab em' and pull em out,,live tube swapping,,it don't get no better.Please take my comment with a grain of salt,,or proper "gloved" attire.

HRDROKN

george daniel wrote: »

Nah,, just grab em' and pull em out,,live tube swapping,,it don't get no better.Please take my comment with a grain of salt,,or proper "gloved" attire.

Ya... those boys get hot! But I did let them cool for 10min.

:cool:

george daniel

Enjoy your new pre--I have an SL 2000 (Dared) that I picked up from a forum member(fishbones) and it's a sweet little pre with tube rolling.I'm hopefully finishing the capacitor upgrade in the am,,we'll see if if gets any sweeter--have fun with yours.

HRDROKN

george daniel wrote: »

Enjoy your new pre--I have an SL 2000 (Dared) that I picked up from a forum member(fishbones) and it's a sweet little pre with tube rolling.I'm hopefully finishing the capacitor upgrade in the am,,we'll see if if gets any sweeter--have fun with yours.

Thanks brother... and let us know that upgrade goes! Always interested in potential tweaks!

HRDROKN

When replacing the four 12AX7 tubes, there are three under the brass shields and one outside on its own... so I'm wondering if I need to change all four at the same time. Thought I read somewhere that two were for the phono section or something to that effect?

HRDROKN

Looks to me that the first 12AX7 is part of the power supply. The second is for the phono stage (along with the single 12AT7, which leaves the two to the far right making up the remainder. So it would seem that those two 12AX7's should be a match pair and can be replaced separately. Hmmmmm.

stuwee

george daniel wrote: »

Nah,, just grab em' and pull em out,,live tube swapping,,it don't get no better.Please take my comment with a grain of salt,,or proper "gloved" attire.

Hehe, I wonder how those super oven mitts that Aussie dude is hawlking on TV lately would work? I think they had seperate fingers... Don't use Playtex Living Gloves...messy...messy...messy..

Scary chick on the box...looks like the last nurse who did my prostate exam <shudders> .

Congrat's on the Dared !!!!

jhoak

HRDROKN wrote: »

When replacing the four 12AX7 tubes, there are three under the brass shields and one outside on its own... so I'm wondering if I need to change all four at the same time. Thought I read somewhere that two were for the phono section or something to that effect?

Check out this post at AudiogoN:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1253132946

By the way... I'm watching your posts about this preamp very closely. My MC-7P should be delivered this Friday. It'll be driving a Bob Latino VTA/ST-120 and a pair of Cornscalas. Can't wait.

engtaz

Great thread jhoak. Thanks for posting.

HRDROKN

jhoak wrote: »

Check out this post at AudiogoN:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1253132946

By the way... I'm watching your posts about this preamp very closely. My MC-7P should be delivered this Friday. It'll be driving a Bob Latino VTA/ST-120 and a pair of Cornscalas. Can't wait.

That was the link I was thinking of! Phil has a schematic of this available as well as a nice write up on his tube experience with this pre.

I'll be watching for you thoughts as well....

jhoak

HRDROKN wrote: »

Phil has a schematic of this available as well as a nice write up on his tube experience with this pre.

Really? I guess I'll need to drop him an email. I would love to see a schematic. If the Dared is anything like some of the other Chinese kit I've seen there is bound to be a LOT of upgrade possibilities.

I've been researching tube possibilities. I'm going to be driving a fairly high gain amp with it so lowering the preamp gain may well be important. Looks like the 5751s might be a good lower gain choice to replace the 12AX7s.

I'll know a LOT more by this time tomorrow.

heiney9

You'll find Dared stuff to be pretty well designed with very good parts right out of the box. So in that regard it's not like a lot of other Chinese tube gear. That said there is always room for improvements but they are likely to have less impact.

All my Dared pieces come with Auricap coupling caps, sure I could upgrade those so some super exotic cap for several hundred $$$ but probably not worth it. Now the input coupling caps are lower quality Carli caps and I could see some benfit there of upgrading to a Multicap or Sonicap, etc.

You get my drift......

H9

jhoak

That's GREAT to hear. It speaks well of a manufacturer when a piece is as good or very nearly as good as it can be right out of the box.

This will be my first piece of Dared kit. I've owned a couple of Yaqin and Ming Da and one other who's name escapes me at the moment. In each case there was opportunity for improvement.

As a rule I don't touch a new piece for the first 100 to 200 hours of play. It give me a chance to let everything "settle in" and me a chance to hear if there are any glaring shortcomings. Other than possibly changing tubes I won't be messing with the new preamp for a while.

george daniel

heiney9 wrote: »

You'll find Dared stuff to be pretty well designed with very good parts right out of the box. So in that regard it's not like a lot of other Chinese tube gear. That said there is always room for improvements but they are likely to have less impact.

All my Dared pieces come with Auricap coupling caps, sure I could upgrade those so some super exotic cap for several hundred $$$ but probably not worth it. Now the input coupling caps are lower quality Carli caps and I could see some benfit there of upgrading to a Multicap or Sonicap, etc.

You get my drift......

H9

Guys-- you might want to consider the Russian K-40's for the input caps--affordable--great tone,,(I have a pair in the input side of my Dared),,only downside is their physical size.YMMV.

jhoak

HRDROKN wrote: »

I'll be watching for you thoughts as well....

Impressive right out of the box without any changes whatsoever. From the "look and feel" the build quality seems excellent.

Sound wise it's quite good but as with all tubed hardware it's WAY too early to make a definitive judgement.

As expected it has WAY too much gain for my system. I only have about 60 degrees of volume control between silent and TOO LOUD. I'll need to find some lower gain tubes for the preamp section.

Based on the last couple of hours of listening I would have to say that I fully expect to become a Dared "fanboy".

heiney9

Dared is solid gear and step or two above typical Chinese gear, but then it's alos reflected in the price too.

If you are using 12AX7's you can use a 5751 to get some lower gain, it won't be much but it should help. If after awhile you still find the gain annoying I believe there is a fairly simple way to swap resistors to lower the gain permanently. Perhaps contact Joe Zhou the US Dared distributor about that.

H9

HRDROKN

The gain is too much for me also... by the time I hit 10 oclock the cops are going to be coming!

I want to try out some 5751's, but I don't want to use them in all four slots... I still don't have a definate answer. I see from the schematic that a 12AT7 is paired (for lack of correct terminology) with a 12AX7 and then two 12AX7's together. So from previous posts the 12AT7 & 12AX7 make up th line stage.

The fourth 12AX7 is in the power supply side.

I'm glad that you are liking it... me too!

:biggrin:

HRDROKN

HRDROKN wrote: »

So from previous posts the 12AT7 & 12AX7 make up th line stage.

Ok.... so now I'm sure that this is the case.

So I would only need to replace the 12AX7 with a 5751 to lower the line stage gain? But I'm not sure if the 5751 would work with the 12AT7 without causing another issue?

Which brings this thought... if I lower the gain 30% at the 12AX7 position, would it make sense to lower the gain the same 30% at the 12AT7 position with a 12AY7 or 12AV7 tube?

heiney9

The 5965 is the 12AT7 equivalent to what the 5751 is to the 12AX7 as far as a lower gain equivalent.

No issues mixing and matching as far as breaking something. As far as sound, well...........that's why we tube roll to find the best combination

Like I suggested before, if you find the gain to high, IIRC there is a resistor(s) that can be changed to lower the gain. Email Joe Zhou at Dared and see what he recommends. If you don't feel comfortable doing it yourself, I'm sure Joe could recommend a shop that would do it for you.

FYI, these lower gain tubes don't lower the gain as much as one would think, 30% is an unrealistic number, think 10% in a real world application. Although using a lower gain tube at both positions *might* lower it a little bit more.

H9

heiney9

Also be sure to buy a true 5751, so many posts on Ebay list multiple titles in their sale title to get the widest number of hits.

Also be aware a 12AV7 is NOT the same as a 5965 even though a 5965 can be subbed for both a 12AT7 and 12AV7. So just because the 5965 can be substituted for both doesn't mean a 12AV7 can be subbed for a 12AT7.

H9

HRDROKN

heiney9 wrote: »

Also be sure to buy a true 5751, so many posts on Ebay list multiple titles in their sale title to get the widest number of hits.

Also be aware a 12AV7 is NOT the same as a 5965 even though a 5965 can be subbed for both a 12AT7 and 12AV7. So just because the 5965 can be substituted for both doesn't mean a 12AV7 can be subbed for a 12AT7.

H9

You Rock!

Thanks!

:biggrin:

george daniel

I've had good luck with the older Tung Sol 5751's.

heiney9

Also if you are looking for a nice pair of 5965's I think I have an extra pair of RCA's I'd be willing to sell you on the cheap.

PM for details if you're interested.

H9

HRDROKN

I have been putting a lot of hours on this pre... mainly to get time on the tubes etc.

I felt like I had a good baseline today so I decided to try out the lower gain tubes on the line stage.

I plugged in a 5965 (for the 12AT7) and a 5751 (for the 12AX7).... she didn't like that! I got terrible random hissing and snap crackle pop! I narrowed it down to the 5965 which was a Sylvania Gold Band Black Plate Gold Pin Tube.

So my question is this a compatibility issue or maybe I got a bad tube? IDK... never heard a bad tube.

heiney9

Sounds like a bad tube if it is cracking and popping and hissing (classic bad tube characteristics). I would try swapping each one in seperately. Be sure to clean the pins really well even if they don't look dirty. I've cured a lot of noisy tubes (as opposed to microphonic tubes) just by giving the pins a good cleaning.

My choice would be to lower the gain at one OR the other position and do an evaluation of each singularly. Then for kicks I'd try both lower gain tubes together. Could possibly be a compatibility issue with using 2 lower gain tubes, but I doubt it.

So try them sigularly for a while. That's how I'd approach it if it was me.

H9

nspindel

This thread ended too soon, I'm wondering where folks got with this pre-amp? I'm highly considering it, and wonder if people held on to it? upgraded it? sold it? will never let go of it? Any advice would be appreciated, especially interested in the phono stage. Thanks.

nspindel

Well.... just bought it!

elia0224

SUBTLE (not suttle)