Best tubes for bass?

[ChopperCharles]

I have a Yaqin MC-100B tube amplifier, and I'm looking to roll some tubes. I'd like to know what the best combination of tubes to use to get really kicking bass. The MC-100B runs four KT88, Four 6N8P, and two 12AX7 tubes.

Thanks!

Charles.

[ChopperCharles]

bump

[Miles Prower]

Originally posted by ChopperCharles
I have a Yaqin MC-100B tube amplifier, and I'm looking to roll some tubes. I'd like to know what the best combination of tubes to use to get really kicking bass.

I've had no problems with bass with either 807s or 6BQ6GTBs. Not so sure how this is a function of tube type. Seems to be more related to having a decent OPT and a good damping factor for the speeks. The former meaning steer well clear of bad OPTs, and the latter by adding enough gNFB to improve damping for bass that isn't sloppy but still packs plenty of "authority".

[Tom Bavis]

Good matching of the output tubes is essential for good bass. Many transformers will lose inductance with even a little DC imbalance.

[richwalters]

Miles is right. There is a bit more to this. The Yaqin 100B is a HIFi amp.
Rather than blame tubes, it's the type of circuit + global nfb and the quality of the output tranny determines the bass extenstion and also how good the power supply can hold the B+ up on transients.
As the thd on the Yaqin 100B amp is quoted at 1.5% (I presume at 1Khz) this is mighty high esp in triode operation where I would be looking under 0.5%. and under UL ? (don't enquire).

I may be an old salt at tube amp design...but I'm well and truly stumped. (baffled). In my tube amps I can get thd as low as 0.05% on full load 100W with parallel p-p pairs using a conventional time tested circuit design using standard EI trannies with Sowter, Majestic and so many others. It's painless ! And still today after 60++ years of tube R&D, manufacturers still shove out HiFi push pull amps on the market with massive thd figures.

Back to the question...Judging by my comments above, the type of tube in the o/p stage then becomes insignifigant. It's the upper freq end that tube quality and type becomes noticable.

To the crux...It looks that todays manufacturers haven't really grasped how to design a tube amp or, as correctly mentioned in another thread just to market and to plunder the customer of his/her cash ? I think so.

With this Yaqin amp.....search engine commentary does indicate some user dissatisfaction.....? with one suggesting a rebuild ?

richj

[ChopperCharles]

I'm a tube noob, I have no idea what all those TLA (Three Letter Acronyms) mean.

I'm personally quite happy with the amp, I don't have "problems" with bass. I just want more of it. I know it's not a tube amp's specialty, and honestly the levels are probably just about right... but I want these Vegas to shine with alternative and club style music for parties.

Also, all the reviews I've read about the 100B have been positive. Where did you see dissatisfied reviews?

To my ear, I can hear very little difference between the Yaqin MC-100B and my buddy's Rouge Audio Tempest amp. We compared them back to back, and yeah, the $2200 amp was better than my $700 amp... but not by much. Both are very musical amps, even with the stock tubes.


Charles.

[richwalters]

Canuck Audio Mart :: View topic - Yaqin MC-100B
In comes the Yaqin MC-100B. Personal experience tells me that the Chinese gear is of questionable quality and needs a lot of work to sound decent. ...
http://www.canuckaudiomart.com/forum...pic.php?t=5680 [Found on Google, Yahoo! Search]

Not to put you off..I may have been a bit harsh..

After all these years working with tube amps, it's high time with all the accumulated knowledge around, it seems the performance of these bemoths is going down... and the thd up..there's really no excuse for it.

richj

[AndrewT]

Originally posted by ChopperCharles
my $700 (tube) amp...

I would expect a set of iron for two channels of 100W that provide a good balance between extended bass, good midrange and realistic trebles to cost near that.
How can anyone add in all the hardware/chassis/components/labour/packaging/transport/sales overhead/profit etc and leave enough for good iron.
That's where the bass went. Less iron and copper saves costs in most of those areas

[KaDe]

Hi
For tube roling I would start with KT88 JJs.
They have that fat tone for bassguitar players

[ChopperCharles]

Richwalters, read that post again. Nobody there actually owned a Yaqin MC100B amplifier, they were just speculating and generalizing on Chinese quality.

Don't bash it until you've heard it. Anyone that wants to give my amp a listen is welcome to stop by. I live in Durham, NC. add at gmail.com to my username and you've got my email address.

Just because I'm looking for a different sound doesn't mean there's anything wrong with the current sound.

Charles.